A beautiful example of outdoor lighting with a modern, minimalist style, the Halton outdoor light is solar-powered with an integrated motion sensor that gives a good quality of light when you need it most. Brushed stainless steel gives it a timeless elegance. A warm white light from an outdoor light that is IP44 rated for safe outdoor use
Complete with integrated control gear
K: 3000 Lm: 310 Lm/W: 53
Weight: 0.9 Kg
This fitting requires 5.88W LED (SMD 3528) Warm White (Included).


Data from Pharmawand - Curated by EPG Health - Date added 27 December 2019
Augmedics, a pioneer in augmented reality surgical image guidance, has announced FDA 510(k) clearance and the U.S. launch of its groundbreaking Xvision Spine system (XVS), the first AR guidance system to be used in surgery.
Xvision Spine allows surgeons to visualize the 3D spinal anatomy of a patient during surgery as if they had “x-ray vision,” and to accurately navigate instruments and implants while looking directly at the patient, rather than a remote screen. The system uses a transparent near-eye-display headset and the components of a traditional navigation system, allowing the user to simultaneously see navigation data as well as the patient without turning to look at a monitor. The augmented reality device accurately tracks the position of surgical tools and overlays a virtual trajectory on the patient’s computed tomography.
Comment: According to Technavio, the global market size for surgical navigation systems is estimated to grow to $900 million by 2020, with compounded annual growth rate (CAGR) of seven percent. Augmedics intends to disrupt this sizeable market with its ViZOR System, an AR surgical visualization system designed to give surgeons “X-ray vision” during complex procedures.


METHOD FOR COLOR LASER MARKING PROCESS OPTIMIZATION WITH THE USE OF GENETIC ALGORITHMS
Environment. Technology. Resources. Proceedings of the International Scientific and Practical Conference
Optimization of color laser marking process mostly depends on effective identification of optimal values of laser marking parameters. This is a difficult combinatorial optimization problem, which is still essential for companies that use laser marking systems. The study proposes a new approach to the process optimization through the use of genetic algorithms, carrying out preliminary experimental investigation, analyzing the laser marking results, and presenting possible improvements to the current implementation of genetic algorithms.


Tired of forcing everyone to scoot closer and closer together whenever you are videotaping? The VCL-SW04 0.45x wide angle lens helps your camcorder pull even the biggest groups into the shot.
- 0.45X wide angle lens for incredible group shots
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Filters and Lens
You're probably familiar with polarizing sunglasses that reduce reflections and cut down glare.
Unlike sunglasses, however, the effect of most professional polarizing filters can be continuously varied and, as a result, go much farther in their effect.
Polarizing filters can:
Note the difference in the two photos below.
Once you understand a polarizing filter's many applications, it can become one of your most valuable filters.
As noted, you can often adjust the degree of polarization. This is done by rotating the double glass elements in the filter.
To eliminate objectionable surface reflections when doing critical copy work, such as photographing paintings with a shiny surface, you can use large polarizing filters over the lights or the camera lens. This is one of the areas where post-filtration can't match the effect of optical filters.
Contrast Control Filters
Although the best of the latest generation of professional video cameras are capable of capturing contrast or brightness ranges up to 700:1, most home television sets and viewing conditions limit that range to about 30:1.
This means the brightest element in a scene can't be more than 30 times brighter than the darkest element -- with any hope of seeing the detail in each. (Digital/HDTV receivers do considerably better, but until everyone has a digital set, we must play it safe.)
"Real world scenes" often contain collections of elements that exceed the 30:1 brightness range.
Although in the studio we might be able to control this with lighting, things become a bit more challenging outside.
For critical exterior scenes the videographer must often consider ways to reduce the brightness range. One way is with a contrast control filter.
Look at the scene on the left below, taken in a setting with contrasty lighting. The use of a contrast control (or low contrast or contrast reduction) filter results in the image on the right.
There are three types of these filters: low contrast, soft contrast, and the Tiffen Ultra Contrast.
Filters for "The Film Look"
Compared to film, some people feel digital video can look a bit harsh, overly sharp, and even brassy.
Studies have shown that audiences have gotten used to and seem to prefer the slightly softer and grainy effect of film -- leading some post-production houses to electronically add these things to video.
Some directors of photography (DPs) people feel it's better to add these things as the video is shot. This link provides more information on achieving this "film look" with optical filters.
A common visual effect, especially in the days of black-and-white film and television, was the night scene shot in broad daylight -- a so-called day-for-night. (In those days, film stocks and video cameras were not as sensitive to light as they are today and you couldn't readily shoot at night.)
But with black-and-white film or video you could place a deep red filter over the lens to turn blue skies very dark, even black. (A red filter subtracts blue.)
That, together with three or four f-stops of underexposure, completed the illusion.
Although not quite as easy to pull off in color, you can simulate the effect by underexposing the camera by at least two f-stops and either using a blue filter or creating a bluish effect when you white balance your camera. (We cover this in a section called "lying to your camera" in Module 18.)
A careful control of lighting and avoiding the sky in scenes adds to the effect.
Embellishments you can add during post-production make the night-time effect even more convincing.
With the sensitivity of professional cameras now down to one foot-candle (a few lux), "night-for-night" scenes are now possible.
Whatever approach you use,
you need to check out the effect using a high quality color monitor
as a reference.
Color Conversion Filters
Color conversion filters correct the sizable difference in color temperature between incandescent light and sunlight -- a shift of about 2,000K.
Although the differences in color temperature among light sources will make more sense after we examine it in a later module, we need to at least mention it in this section on filters.
Even though professional cameras can electronically take care of minor color correction, colored filters are best for major shifts, such as the difference between indoor and outdoor lighting.
Two series of filters have long been widely used in motion
picture production: the Wratten #80 series, which are blue and convert incandescent light to
the color temperature of sunlight, and the Wratten #84 series, which
are amber and convert daylight to the color temperature of tungsten
Since video cameras are optimized for one color temperature, videographers will generally use these filters to make the necessary "ballpark" adjustment. The "fine tuning" is then done electronically.
Filters For Fluorescent Light
Some lighting sources are difficult to correct.
A prime example and one that videographers frequently run into is fluorescent light. These lights are everywhere, of course, and they can be a problem.
Although in recent years camera manufacturers have tried to compensate for the greenish cast that fluorescent lights can create, when it comes to such things as getting true-to-life skin tones (and assuming you can't turn off the lights and set up your own incandescent lights), you may need to experiment with a fluorescent light filter.
We say "experiment" because dozens of fluorescent tubes exist, each with different color characteristics.
But one characteristic all standard fluorescent lamps have is a "broken spectrum" or gaps in the range of colors they emit.
The eye can more or less "smooth over" these gaps when it views things firsthand, but film and video cameras have problems.
Some other sources of light are even worse -- in particular the metal halide lights often used in gymnasiums and for street lighting. We discuss this in more detail in the lighting module on color temperature.
Although the public may accept these lighting aberrations in news and documentary footage, it's a different story when it comes to most commercials and dramas.
As we will see, some color-balanced fluorescent lamps are not a problem, because manufacturers design them specifically for TV and film work. But don't expect to find them in schools, offices, or boardrooms.
Special Effect Filters
Although scores of special effect filters are available, we'll highlight four of the most popular: star filters, starburst filters, diffusion or soft focus filters, and fog filters.
Star Filters - You've undoubtedly seen scenes in which "fingers of light" project out from the sides of shiny objects -- especially bright lights.(Note photo above.)
The camera operator creates this effect with a glass star filter that has a microscopic grid of crossing parallel lines cut into its surface.
Notice in the picture above that the four-point star filter also softens and diffuses the image.
Star filters can produce four-, five-, six-, or eight-point stars, depending on the lines engraved on the surface of the glass. The star effect varies with the f-stop used.
A starburst filter (on the left, below) adds color to the diverging rays. Both star filters and starburst filters slightly reduce the sharpness of the image, which may or may not be desirable.
Soft Focus and Diffusion Filters - To create a dreamy, soft focus effect, you can use a soft focus filter or a diffusion filter (on the right above).
These filters, which are available in various levels of intensity, were often used in early cinema to hide aging signs in actors. (Some stars even wrote this requirement into their contracts.)
You can achieve a similar effect by shooting through either a fine screen wire placed close to the lens or a single thickness of nylon stocking.
The f-stop you choose will greatly affect the level of diffusion. It's important to white balance your camera with these items in place.
Fog Filters - You can add a certain amount of "atmosphere" to dramatic locations by suggesting a foggy morning or evening.
Without relying on nature or artificial fog machines, fog filters can create somewhat the same effect. (Note the photo above.)
In Using Filters
Using a filter with a video camera raises the black level of the video slightly. Because this creates a slight graying effect, it's advisable to readjust camera setup or black level (either automatically or manually) whenever a filter is used.
Unlike electronic visual effects that an editor creates during postproduction, the optical effects a videographer creates while recording a scene can't be undone.
To reduce the chance of unpleasant surprises, you need to carefully check the results with the help of a high quality color monitor as you shoot.
Camera Filter Wheels
As we've noted, professional video cameras have filter wheels behind their lenses that can hold a number of filters. You can rotate individual filters on each wheel into the lens light path as needed.
Note the two filter wheels in the photo on the right. One is labeled 1 through 4 and the other A through D. Two filters can be used at once. For example, 2-B would be a 1/4 ND (neutral density) filter, along with a 3,200K (standard incandescent light) color correction filter.
Filter wheels might also contain the following:
Although the filters shown are located behind the lens, to be most effective you must mount some filters, such as polarizing filters, in front of the lens.
A matte box is a device mounted on the front of the camera that acts both as an adjustable lens hood and a way of holding square or rectangular gelatin filters. These are much cheaper than the round, glass filters.
Matte boxes can also hold small cutout patterns or masks. For example, you could use a keyhole-shaped pattern cut from a piece of cardboard to give the illusion of shooting through a keyhole (although, unlike earlier days, we can see through very few keyholes today).
Most of the effects that matte boxes formerly created can now be more easily and predictably achieved electronically with a visual effects generator.
A "bug's eye" view of subject matter is possible with a periscope/probe system.
This low angle is useful when actors are electronically keyed into realistic or fantasy miniature models. We can enhance the effect with the wide-angle views of the four lenses that come with the system.
In the photo on the right, the camera operator uses a lens probe to film a miniature prehistoric setting that will later come to life in a full-scale effect.
Although this is a film camera, it has a video viewfinder to provide immediate feedback on the image captured on film. (Note the video monitor.)
In the next section, we conclude the discussion of lenses and lens attachments.
Video Projects Revision Information
Issues Forum Author's Blog/E-Mail Associated Readings Bibliography
Index for Modules To Home Page Tell a Friend Tests/Crosswords/Matching


So - you want a splendid holiday microscope? (II)
As we did already discuss the MBS-10 extensively elsewhere we will concentrate on the entry-level compound microscope sold under the name BTC BIM135T.
There was also a smaller sister model, priced for about 60 US $ less, called "BTC BIM105T". It has no condenser adjustment knob and more modest achromatic objectives (not semi-plan). Overall those prices might still look like a lot of money for most of our readers. But we shouldn't forget that this kind of microscope would have cost about 2,000 US $ in the 1970s.
We were curious whether the optics and mechanics might come
close to our older "branded" microsopes as there are many contradictory
statements about this topic all over the web, for example:
So what ???
Basic use, focusing and light are fully functional and all movements are working (no disturbing backlash, no vibration tendency when focusing etc., no light flickering). The image is quite clear, the field of view not luxurious but appropriate and sufficiently flat. Obviously the design is oriented towards the beginner with no special refinements or complications. Just switch the light on, choose the appropriate objective needed, focus - that's it. The visual image impression is flawlessly, not worth further discussion with respect to practical use. The instrument can be used with almost no contraints for water droplet microscopy and even for use with modest incident light, as might become clear from the images below where the incident light is coming from aside:
Some limitations became apparent when using the microscope for the study of the marine tardigrades. As already mentioned in our last issue the field of view shows an uneven brightness, therefore doesn't look as clean as with our classical microscopes. The so-called "Köhler" illumination as recommended by microscopy priests is not available. As a consequence some light energy is dissipated and the 20W source might appear a little bit too dark in extreme situations. Nevertheless the instrument is quite usable as a holiday microscope. The following photograph might serve as an example to make up your mind:
Summary: this microscope is by no means a high-end scientific microscope but it is well suited for the beginner, also a more ambitious beginner with budget restraints. It can be used for photography as well but it is not as flexible and not as upgradable as the more expensive systems.
© Text, images and video clips by
Martin Mach (firstname.lastname@example.org).


Thermal Fusion Night Vision Bincoulars with GPS, digital compass and marking
China TianYing TL300 thermal fusion night vision binoculars is enhanced dual channel binoculars, uses day and night type night vision technology fused with thermal imagery, thereby bridging the gap in performance and capability for both of these sensors, provides the operator with significantly improved targeting and identification in all conditions.
Integrated night vision allows to detect man out to 600m and recognize man out to 400m in 1/4 moon, integrated thermal imaging allows to recognize man-size targets in excess of 600m.
This gives the warfighter substantially increased situational awareness, because threats can be detected in virtually any environment. Bad guys that would normally be camofluaged in foliage, rock formations, etc can now be easily detected from a safe distance.
By prominent marking capability, operator can quickly find cloaked and camouflaged object in day and night, especially effective in urban operations. Option add digital compass and BDS or GPS function.
1, Why many thermal fusion binoculars price is very cheap?
Because their binoculars is thermal fusion daytime visible light CCD camera, their CCD camera is only work on daytime, but they are only simple fusion, also their fusion effect is not good too.
2, Why image fusion need environment mode?
Because image fusion environment mode will add fusion effect.
3, Why image fusion need marking function?
Because marking function will sharpen and highlight fusion effect, also then good marking can quickly find cloaked and camouflaged target.
4, Why this fusion binoculars price is higher than other company' fusion binoculars?
Because quality is different,if used for same standard, then our price is very cheap.
You need know that only good image quality military thermal binoculars price or only good image quality military day and night type white autogated night vision binoculars price is not cheap.
TL300 Enhanced Thermal Imaging Binoculars Fusion Day and Night Vision Binoculars Specification:
|Thermal imaging channel
|Uncooled Vanadium Oxide
|≤ 45mK 25ºC
|Field of View,°,
|16 x 12°
|≥600m for human, ≥1500m for vehicle
|≥400m for human, ≥800m for vehicle
|Low light night vision channel
|day and night type solid-state night vision
|Field of View,°
|16 x 12°
|Detect range( day time)
|≥800m for human, ≥1500m for vehicle
|Recognize range (0.001lux night)
|≥150m for human, ≥300m for vehicle
|Digital Compass and BDS or GPS Function
|BDS or GPS
|0.39'' 1024 x 768 OLED
|Diopter adjustment, diopter
|-4 to +2 D
|thermal imaging mode, low light mode, fusion color mode, fusion black and white mode
|Image fusion environment mode
|jungle mode, snow land mode, ocean mode, city mode, desert mode
|Photo and video
|BMP photo, AVI video, playback, delete, search.
|Storage photo and video
|TF card 32G
|Q9 CCIR (PAL compatible)
|USB and RS232
|Power Supply, V
|3 x 18650 type rechargeable lithium battery
|Operating time, hour
|≥ 5 hours with built-in 3 pcs 18650 batteries.
|- 40 … +55
|Storage temperature, °C
|-50 ... +70
|Level of Protection
|Tripod mount, inch
|205 x 160 x 70
|Weight (with batteries), kg
|*- Technical information is subject to change without notice.
** - Depending on the region of sale.
TL300 Fusion Thermal Imaging Night Vision Binoculars - desert mode
thermal imaging working distance contrast night vision working distance, you can see their working distance is similar, but in 380m can recognize human.
thermal imaging working distance contrast night vision working distance, 650m show human image size is very small and especially night vision.
TL300 thermal binoculars recognize 900m vehicle
TL300 night vision binoculars recognize 900m vehicle, by image can see Halo size, this is typical Gen 3 technology, day and night type night vision is white autogating technology.TL300 Fusion Thermal Imaging Night Vision Binoculars - jungle mode
You can quickly find weak infrared radiation target and the tree shade target by the video.


We have launched our low light USB 3.0 camera board – See3CAM_CU30, based on the 1/3-inch AR0330, a 3.4 mega pixel image sensor from OnSemi™. This OEM camera can capture images at 0.1 Lux, ideal for low light surveillance applications. The See3CAM_CU30 streams video high definition(HD) video 720p@60fps and Full HD video, 1080p@60fps in both uncompressed (UYVY) and compressed (MJPEG) formats.
With the excellent image quality, the See3CAM_CU30 is an ideal camera for low-light applications such as home-surveillance, in-car security cameras, webcams, day-night cameras etc. The high-performance on-board ISP provides not just excellent image quality, but also allows customers to adjust all the camera parameters to meet their application requirements.
Customers interested in evaluating our ultra low light USB 3.0 camera can buy See3CAM_CU30 samples from e-con Systems™’ online webstore with option to buy with or without the lens. For more information, please visit 3.4MP Low light USB 3 Camera. Also watch demo video at https://www.youtube.com/v/bpaArU3NqAg


Proceedings PaperThe Scatterometer For DIRBE
|Format||Member Price||Non-Member Price|
A technique for monitoring the degradation in performance of an infrared instrument caused by contamination of the primary mirror is needed. A scatterometer, measuring the light from an off-axis source transmitted through the instrument, is proposed. The design and analysis of this device is described.


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Prizm™ is a revolution in lens optics built on decades of color science research. Prizm™ lenses provide unprecedented control of light transmission resulting in colors precisely tuned to maximize contrast and enhance visibility.


LASER - Pragnienie miłości /Czekoladka/ - teledysk do filmu Disco Polo - śpiewa Dawid Ogrodnik
Powerful 4500mW Blue Laser Demonstration
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A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The term "laser" originated as an acronym for "light amplification by stimulated emission of radiation". The first laser was built in 1960 by Theodore H. Maiman at Hughes Research Laboratories, based on theoretical work by Charles Hard Townes and Arthur Leonard Schawlow.
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Biomedical optics is one of the fastest growing areas of research. The non-ionizing nature of light applied for investigation and detection of abnormalities in human tissues make this area very attractive for development of new diagnostic techniques and modalities (Wang, 2007). The optical spectra provide biochemical and morphological information about the tissue under investigation based on its absorption, reflectance, fluorescence and elastic scattering properties (Wang, 2007; Tuchin, 2002). Many techniques based on the recent progress in optics have been developed for biomedical applications. Fluorescence, absorption and diffuse scattering spectroscopy have been widely applied as probes acquiring information about physical, chemical, or physiological processes in the tissues. These methods have been proposed to be used by the medical community in view of extending the capabilities of the standard diagnostic modalities that have already been introduced in the clinical practice, as x-ray, magnetic resonance and ultrasound imaging.
Laser-induced autofluorescence spectroscopy (LIAFS) could be utilized to quantify differences between normal and abnormal tissues
Laser-induced autofluorescence spectroscopy is very promising from a technical point of view due to the easy coupling with optical fibres for delivering the excitation light to every part of the human body without significant losses of light power, as is the case of incoherent light sources, as well as because of the possibility to use information from naturally occurring endogenous fluorophores, without adding external fluorescent markers. LIAFS is also notable among the other non-invasive diagnostic techniques, as it offers real-time detection and differentiation of the lesion investigated with promising precision, selectivity and specificity (Bigio, 1997; Bachmann, 2006). The fluorescent technique is widely applied to cutaneous lesions’ investigations, including erythema (Sinichkin, 1998), psoriasis, vitiligo (Borisova, 2000), and skin cancer (Wang, 2006; Troyanova, 2006). This method yields information about the biochemical composition of the tissue under study.
On the other hand, diffuse reflectance spectroscopy is mainly providing morphological information concerning the tissues. The scattering intensity and spectral distribution of the signals detected could give information about the scatterers’ size and distribution (cells, nuclei, etc.). Most of the tissue pathologies, including tumours, exhibit significant architecture changes on a cellular and sub-cellular level. The elastic scattering of light penetrating into the tissues depends on this alteration in their architecture, so that the back-scattered signals detected could be used for determining pathological structural changes occurring in the organ under study (Morant, 2003). As the diffuse reflectance signal detected is a superposition of diffuse scattering and absorption from tissues pigments, the resultant spectrum on the tissue surface reveals also information about the main absorbers in the biological tissues, such as haemoglobin and melanin in the skin and its pathologies. To benefit fully from reflectance spectroscopy’s advantages, one needs to relate the spectral features with the morphology and biochemical composition of the tissue investigated. (Tuchin, 2002, Borisova, 2006).
Combination of fluorescence and reflectance optical techniques could rapidly improve the sensitivity and specificity of cutaneous tumours’ diagnosis (Borisova, 2008). Using imaging analysis techniques in the processing of fluorescence and reflectance spectral data received from cutaneous pathologies could further improve the diagnostic accuracy (Borisova, 2008).
Our work is a stage in the development of methods for skin cancer diagnostics on the basis of optical spectra. The preliminary analysis showed that the spectra of lesions differ from those obtained from normal tissue, with the differences observed depending on the type of pathology. A more “damaged” tissue changes the colouring more intensively. If a lesion’ area could be localised correctly, it would provide more precise information about this lesion’s structure. In addition, not only does the intensity value of the reflected/emitted light vary from patient to patient, but it also depends on the position of the tested area inside a given lesion. We proposed that the variations in the reflected/emitted value of the light could be caused by two possible reasons:
different degree of “damaging” – lesion stage of development, and
different thickness of the suspicious lesion area.
The specific features of the spectra are suitable for the development of a hybrid diagnostic algorithm (including both image and spectra) for detection and discrimination of different type of tissue damaging. We applied this approach to studying skin cancer in an attempt to separate the melanoma from benign and dysplastic melanin-pigmented lesions. The ultimate goal of the investigation is developing a reliable technique for predicting the type and level of skin damaging and the stage of its progress.
2. Basic theory
2.1. Image processing
The aim of image processing is obtaining an image with a value of the lightness of pixels, which depends on the saturation of the damaged tissue. CIE.Lab is a standard for estimating of colours using features of the illuminating light source.
The system presents the colours as relative lightness and chromaticity that consist of two components: a - a red- green axis, and b - a yellow-blue axis. The other parameter - chroma, is calculated as the distance of the particular chromaticity from the centre of the area (Fig. 1) and corresponds to the visible saturation of the colours.
If we use another coloured light to illuminate the object, all the visible colours would change. However, the calculated coordinates (eq. (1)) in the Lab chromaticity area will keep their position, since the colour of the source becomes achromatic.
where for and otherwise.
If we use another colour as a “referent white”, all available colours’ coordinates would be changed, but the white point again will be at the centre of the chromaticity area with no saturation. Thus, if the healthy skin colour is used as a “referent white” point, all changes of the pigmentation could be described by chroma. Applying this to digital images, the colour of the tissues transforms to grey levels and the areas whose colour differs from the “healthy” one will occur with higher intensity. However, the images consist of pixels whose RGB signals measure relatively and reproduce the colorimetrical features of the objects. Concerning equations (1), a transformation from RGB to XYZ is needed to obtain the Lab parameters and chroma. The relation depends on the chosen area of Locus that needs to be converted and are established for several more frequently used spaces – sRGB, AdobeRGB, ProPhoto etc. given as values of the coefficients cij in equation (2).
Applying these transformations to images of lesions we achieve a decrease in the saturation of the healthy skin surrounding the damaged one. The sequenced linear contrast stretching of the whole image improves the visibility of the tested area by highlighting the saturated pixels and allowing the lesion localization. The saturation could be imaged by transforming each pixel’s chromaticity to a grey level presenting their chroma.
2.2. Spectra processing
The aim of the processing is to highlight the peculiarities of the distribution obtained from suspicious tissues. We used a simple technique developed for the reflected spectra also described in monograph about chromatic monitoring [ed Jones, 2008] that ensures a comparison between the healthy and the tested unhealthy tissues’ spectra. We calculated the ratio “healthy skin” to “tested skin” spectrum (Fig. 2)
The result is a new distribution, which is a straight line if the two spectra are proportional to each other, or otherwise may have any other shape. This gives rise to a possibility to overcome the ambiguities resulting from the different patients’ states and to extract only the peculiarities common for the disease.
3. Experimental set up
In our investigation we used images and spectra of melanin-pigmented cutaneous benign lesions obtained from 30 patients, dysplastic nevi - obtained from 18 patients, and lesions of malignant melanoma obtained from 27 patients.
The images were obtained from simple photographs taken by a photo camera and processed by a specially prepared computer program that transforms the colour parameters by the sRGB standard. The fluorescent spectra were obtained using three different excitation sources with maxima of the emitted light at 365, 385, and 405 nm, respectively. The emitted fluorescence is registered by a fibre optic micro spectrometer (USB4000, “Ocean Optics,” Inc., Dunedin, USA). A high-sensitivity linear CCD detected the reflected light dispersed by a grating with 600 lines/mm, with the total spectral resolution of the micro spectrometer being approximately 2 nm. The same device was used for registering the reflectance spectra. All spectra were limited into the range of visible light between 420 and 780 nm. The intensity and shape of the curve of reflected/emitted spectra in different conditions could be estimated in the cases of different patients and different points of obtaining the spectra inside of the lesion.
The results were analysed based on two criteria:
Significant signal level dependence on the reflection and excitation light wavelength,
Coincidence of the shape of the spectra ratios obtained from different patients and different points of registering depending on the diagnosis.
4. Results and discussion
4.1. Benign nevus
Figure 3 shows the initial image of a benign nevus lesion, the image of healthy tissue used for obtaining the values of XnYnZn parameters, and the grey “chroma” image after processing. The damaged area is inhomogeneous. The pixels that pertain to it could be extracted by simply setting a threshold to the grayscale. One could expect that spectra registered from the central and the peripheral area of the spot should be similar in shape and level.
Figure 4 shows the reflected and emitted spectra of the central area obtained from three different patients denoted by P1, P2 and P3. The intensity of the reflected light changes from patient to patient, but, as it is seen, the curves have similar shape. In what concerns the intensity of the emitted spectra, a higher level is present in the case of stimulation with the wavelength of 385 nm. Figure 5 shows the reflected and fluorescent spectra of the central and peripheral areas and the spectra of the healthy areas. The comparison of the shapes of these spectra allows us to suggest that only 385 nm is suitable for seeking similarity. Concerning the reflected spectra, the shape of the curves does not depend on the positions. This fact is confirmed by the spectra ratio given in figure 6.
The suggestion that the spectra do not depend on the position inside of the lesion is valid for the intensity in practically all cases of fluorescence; this holds true for the shapes only if stimulation is carried out at 385 nm. Similarity is present in the shapes of the reflected spectra only, but not in their intensity.
4.2. Dysplastic nevus
Figure 7 illustrates the results of applying the techniques discussed to the image of a dysplastic nevus. The damaged area has clear outlined borders and could be easily extracted again by setting a threshold to the greyscale. The internal structure shows a low-density area concentrated into the centre of the lesion, and higher density near the borders. It could be assumed that the spectra would have different shape and intensity in dependence on the position of registering.
Figure 8 shows reflected and fluorescent spectra of the central area obtained from three patients denoted again by P1, P2 and P3. The intensity of the reflected light is almost similar for the different patients, but the shape of the curves is different. Concerning the emitted spectra intensity, a higher level is seen again in case of stimulation at 385 nm. The next figure 9 also shows the reflected and fluorescent spectra of the central and peripheral areas and the spectra of the healthy areas. It could be seen that the shape of the fluorescent spectra does not depend on the position in all wavelengths stimulations tested. However, only the stimulation with 385 nm gives simultaneously a similarity between the spectra ratios and sufficient differences from the other spectra ratio (figure 10) in the cases of stimulations at 365 and 405 nm.
4.3. Malignant melanoma
A malignant melanoma lesion is presented in fig. 11 by images resulting from two different processing: the one described above, the other using the program of MoleMax system. The latter uses ABCD criteria to set a diagnose by image analyses. The technique of greyscale „chroma“ image shows better visibility of the differences inside the lesions than the method used in the MoleMax program. The density spreading implies the absence of a relation between the position (centred or near borders) and the shape and intensity of the spectrum.
Figure 12 shows reflected and fluorescent spectra of the central area obtained from three patients denoted by P1, P2 and P3. The intensity of the reflected spectra varies from patient to patient. The same is valid for emitted spectra independently of the stimulation wavelength. The shapes of the spectra obtained from different areas of one patient are similar, but those of the spectra from different patients are different (figure 13). The spectra ratio given in figure 14 show different intensity, but the shape obtained by stimulation at 365 and 385 nm of peripheral areas are similar. The same applies to the reflected light spectra for.
Many technical advances and new optical methodologies for early detection of cancer have been recently developed, but there still exist considerable challenges concerning the precise diagnosis and differentiation of cutaneous malignant lesions. Most dermatologists still rely on their practical experience in visual evaluation of pigmented lesions. It is well known that the diagnostic accuracy depends on the clinical experience of the specialist (Morton and Mackie (1998)). In general practice, where such experience is low, diagnostic accuracy is quite bad (Bedlow 1995). In the early stages of the disease, the diagnosis is difficult even for experienced clinicians.
Within the wavelength range 400 – 800 nm, which we used in our observations, the stratum corneum, epidermis and dermis have relatively high scattering coefficients and lower absorption coefficients, particularly at longer wavelengths. Consequently, the spectrum of white light passing through such a tissue can be affected by the various components and thus become biased towards the longer wavelengths (Jones, 2000).
To benefit fully from optical spectroscopy’s advantages, one needs to relate the spectral features with the morphology and biochemical composition of the tissue investigated. Account needs to be taken of various other skin tissue characteristics, such as melanin content in the epidermal layer, haemoglobin derivatives in the dermis and their influence on the detected spectra, so adding to the complexity of the conditions to be monitored.
Chromatic techniques have the potential for providing a means for quantifying the tissue spectral characteristics selectively under such conditions and for producing an assistive automated diagnosis means. When a combination of fluorescence, reflectance and chromatic techniques for analysis is applied, the diagnostic accuracy for malignant melanoma detection reaches 90 % (Borisova, 2008). In the situation when only one of these analytic techniques is applied, the diagnostic accuracies achieved are very similar for all three methods – about 70%.
Such an increase in diagnostic accuracy (by 20 %) demonstrates that applying chromatic techniques for monitoring biological tissues via the fluorescence, reflectance, absorption and scattering of polychromatic light could be extremely useful in tumour detection and evaluation. Therefore, unification of spectral and chromatic techniques in a common diagnostic tool is a very promising future step in the development of medical diagnostic systems, as it leads to increasing the diagnostic accuracy (ed. Jones, 2008, Borisova 2008) and allows one to develop computerized automatic systems for diagnostics decisions when one investigates cutaneous pathologies.
There are two common problems that impede one in obtaining optimal results.
First, the greyscale “chroma” image resulting from the image processing depends on the healthy area; thus, any sparkles are able to produce incorrect chroma spreading inside the lesion. The problem could be avoided by controlling the image registration.
The second problem is related to the wavelength interval of visibility of the stimulating laser pulse. In fact, the interval under 480 nm becomes useless.
Overcoming these problems is a task of data registration and do not have relation to the processing mentioned above.
Final greyscale images yield enough information about the density spreading inside one lesion. It makes it possible to control precisely the position of obtaining the spectrum.
Calculated spectra ratios emphasize the differences resulting from skin damages independently of the patients. A simple analysis shows that the data from emitted spectra after stimulation at 385 nm are suitable for setting a diagnose. For a benign nevus, the data could be extracted from the any part of the lesion; for the dysplastic nevus, from the centre of the area; and from the peripheral area for the malignant melanoma.
The spectra ratios from reflectance calculated for a benign nevus could be distinguished from the spectra ratios for a dysplastic nevus, while the same spectra ratios for malignant melanoma clearly differ from the others.
Summarising the test results, we can conclude that the techniques described above form a good basis for the development a non-invasive method for estimating the type of skin damage.
This work was supported by the National Science Fund of Bulgarian Ministry of Education, Youth and Science under grant DO-02-112/2008 “National Centre of Biomedical Photonics”.


We report the application of Optical Coherence Tomography (OCT) to various types of human cases of otitis media (OM). Whereas conventional diagnostic modalities for OM, including standard and pneumatic otoscopy, are limited to visualizing the surface information of the tympanic membrane (TM), OCT is able to effectively reveal the depth-resolved microstructural below the TM with a very high spatial resolution. With the potential advantage of using OCT for diagnosing different types of OM, we examined in-vivo the use of 840 nm wavelength, and OCT spectral domain OCT (SDOCT) techniques, in several human cases including normal ears, and ears with adhesive and effusion types of OM. Peculiar positions were identified in two-dimensional OCT images of abnormal TMs compared to images of a normal TM. Analysis of A-scan (axial depth-scans) data from these positions could successfully identify unique patterns for different constituents within effusions. These OCT images may not only be used for constructing a database for the diagnosis and classification of OM, but they may also demonstrate the feasibility and advantages for upgrading the current otoscopy techniques.


Table of Contents
Best Thermal Rifel Scope
Technology used to create thermal scopes used to be prohibitively expensive. Best Thermal Rifel Scope. This meant that they were available only to those with large pockets and large budgets, like the military and larger law enforcement agencies. With the rapid advancements of technology, price point on thermal scopes has dropped significantly, and they have become more accessible than ever before.
The increasing availability of thermal scopes has resulted in an increase in demand for hunter-based activities that are nocturnal, such as hog and coyote. This increasing demand from consumers has prompted many companies to get into the market and make thermal scopes available to a greater number of hunters and shooters than ever before. Whether you’re looking to get your first one or upgrade to a more sophisticated model, let us show you some options for the best thermal scopes so that you too can join in the action.
The Best Thermal Scopes For 2022
- Best Value for Money: OPMOD Thor LT 3-6x
- Best Over $5000: Trijicon IR Hunter MK3
- Best Thermal Scope under $5000: AGM Secutor TS25-384
- Best Thermal Scope Under $1000 ATN Thor HD 384 2-8x
- The Best Value Thermal Scope: ATN Thor 4 384 1.25-5x
- Ideal for hunting: ATN Thor LT 160 3-x
- The Best Hog Hunting Thermal Scope: Sig Sauer Echo 3
- Best Clip-On Thermal Scope Burris BTC 50
- The best surveillance tool: Trijicon IR-Patrol IRMO 300 Rifle Kit
Things to Consider Before Buying an IR Scope
You’ve probably figured out already that the best thermal scopes aren’t cheap. A majority of people don’t invest a sizable chunk of change on a thermal scope on a whim. There are some things that you should be thinking about before deciding what thermal scope is best for you. (Or, honestly whether you really require one or you could use the money elsewhere.)
If you search on the internet, you will find companies offering thermal scope rentals. This is a great way to try out various models and gain a sense of what you like best prior to making a purchase. Best Thermal Rifel Scope.
Obviously, the final decision is up to you however, if you do decide that your next major gun-related purchase will be an thermal scope Here are some of the things you should consider prior to parting with your hard-earned money:
There’s plenty of technology in the thermal scope, and it’s must have some type of battery that can power it. There aren’t all batteries equal, and so you want to be sure that your thermal scope will stay powered up for as long as you need it. That means you should think about how long you plan to be using the scope for in one time period. Also, how long does it take to chargeit, and what will extra batteries run.
Some thermal scopes offer WiFi, GPS, Bluetooth, and more. These are all really cool options however you need to take a look at what you’ll be using the thermal scope for and whether or not those additional features are worth it or not. For example is it really necessary to be able to stream your scope image to a mobile device?
Price and Budget
The best thermals are going to exceed $5000. While these are often the best-of-the-best scopes you can buy, you’ll get practical usage from models in the $2000-$5000 price range. If you’re looking for a low-cost thermal scope under $1000, you’ll not find one. There are some thermal scopes under $2000, but they must be specific to the brand in order to get good warranty and money-back guarantee coverage as quality control issues must be expected in this price range.
Size And Weight
Thermal imaging scopes are heavy and big. Average weight for a standard thermal rifle scope is about 2 pounds. Lightweight thermals weigh between 1-1.5 pounds, which is similar to standard morning rifle scopes. Although thermals could be about the same length of traditional rifle scopes, and even shorter, the internal components needed to offer thermal imaging makes them wider. Their overall weight and size can affect your shooting or tactical weapon and scope system.
A lightweight and compact option is to look into a clip-on system. In addition to reducing the weight and size, but they’re designed to be used on top of your daytime scope and are easily removed and attached.
Thermals can give you over 1000+ yards of range of detection on targets, regardless of day and night conditions. However, the distance at which you can identify and recognize the target will be significantly shorter.
These ranges can differ among manufacturers models, models, and the quality. The thermal detector’s sensitivity is the most important factor you need to study. A higher magnification will help quickly recognize and identify distant targets, however it may also lead to poor pixelage resulting in a grainy picture. Display resolution will also determine what the image quality is. sight picture. Best Thermal Rifel Scope.
Which is Better Thermal Or Night Vision?
Instead of looking at whether night vision scopes are better than thermal or vice versa, instead focus on whether night vision scope can be superior than thermal or vice versa, the primary question is:
Which one is the best to meet your needs and budget?
When you’re done with this guide, you’ll know exactly the answer to that.
Let’s get started!
Night vision operates by using light or reflections of light and intensifying the light into a crystal clear image.
Therefore, it needs some type of ambient light for it to work.
If you’re shooting at night, the moonlight and stars usually provide enough light. The latest models feature infrared illuminations that function as flashlights to illuminate the scope but aren’t visible to the naked eye.
If you’re looking through the market of night vision optics You’ll find different ratings for them — Gen Iand II, or III. In simple terms, the more the level of the generation, the higher the quality.
Also, you’ll see a more recent category of night vision scopes known as Digital Night Vision.
The normal night vision displays the traditional black and green while the updated digital night vision is usually presented in white and black on the LCD screen.
- Night vision delivers a higher quality image.
- It permits you to distinguish between finer details. Additionally, night vision scopes are cheaper and more small in size. It’s not affected by cold weather.
Night vision technology has been in use a lot older in comparison to thermal optics. Night vision scopes can be found be mounted on rifles, and are more sturdy, durable, and absorbs recoil like a pro.
- Its requirement for ambient light is what makes night vision limited.
So unless you have an infrared light source that isn’t in use, it’s useless in darkness. It’s not recommended to use it in sunlight as it could be permanently damaged if exposed to a bright light.
Thermal scopes detect heat or radiation given off from any living thing. Thermal imaging employs a specific type of lens that concentrates at infrared light and generates an image known as a thermogram. This thermogram then transforms into electrical impulses , which then form the image you see that appears on the screen. Best Thermal Rifel Scope.
- The thermal vision is a little more flexible as it is able to be utilized in any light condition. In reality, one of the greatest benefits for thermal imaging scopes is that they work well in both daylight and night and don’t necessitate infrared light. On top of that they allow you to be able to see through smoke, dust and fog easily. This is the reason firefighters utilize thermal technology.
- One of the main drawbacks for thermal imaging can be that it is quite heavy to transport. They are also expensive and you might have undergo training in order to interpret the images correctly. The battery life is often short, while the overall quality of an image can be adversely affected by colder temperatures.
Frequently Asked Questions
What is the length of time the Thermal Scope last?
In the an average thermal scopes run for about eight hours with a single charge. Various models will vary between 2 to 10 hours. Recently, ATN has managed to manufacture ultra-low consumption thermal scopes which provide more than 10 hours of continuous usage.
Why is it that Thermal Scopes are so expensive?
It is generally true that thermal scopes cost a lot because of the advanced technology components. There are also cost differences for various features, such as Bluetooth connectivity and palette mods or ballistic applications, and more. But, as it happens, thermals start at a reasonable price point of $1000.
How far can Thermal Rifle Scopes View?
The distance thermal rifle scopes can see will depend on the display resolution and magnification settings. Generally, even basic thermals are able to detect the heat signatures at 1,000or more yards. The most advanced thermals are able to detect heat signatures that extend beyond the 4,000-yard mark, but target identification is another matter.
Can You Make Use of Thermal Scope in Daylight?
Contrary the night vision scopes unlike night vision scopes, you can use the thermal scope in the daytime without damaging components. Instead of increasing light, thermal scopes read heat signatures. Dual-use capabilities are one of the main benefits of choosing thermal instead of night vision and making the most of your purchase. Best Thermal Rifel Scope.


Lee Filter Roll 250 H. Wh. Diff.
- Softens Light Output
- 0.75-Stop Reduction
- 60% Light Transmission for 6774K
- Heat Resistant to 356°F
- Polyester Construction
The 250 Half White Diffusion Filter from LEE Filters is designed to soften the output of a light fixture. This filter is constructed from polyester that is heat-resistant to 356°F.
Under 6774K Source C light, the 250 Half White Diffusion Filter provides a 0.75-stop value, transmitting light at 60%.
- Size: 762 x 122 cm, normal
- Lee colour number: 250
- Colour: Half White Diffusion


Join Date: Dec 2011
Location: Montreal, Canada
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I had this kind of TV in my office for over a year now... 52 inch branded SuperD.
Its pretty sweet but seriously lack in definition... I doubt this technology will be ready before 4K resolution TV (4x HD resolution). We're planning on using these as advertisement platform.
It use a thick Glass substract filled with million of prism that redirect light from different pixel to each eye.
It require to be sit in a sweet-spot (7 sweet-spot available in the TV I've witnessed, but you can nod your head and partially look behind object.
A 1080p TV with that thick glass substract look like a 320l definition... but the 3D effect is stunning and pop way out the screen.
How was the resolution on that one? maybe it use a different technology then the one I saw.


Image Acquisition and Measurement Software
Specifically developed for microscopy applications, IC Measure is a powerful end user application for measurement and image acquisition using any video device, manufactured by The Imaging Source.
IC Measure Features
IC Measure provides multiple tools for manual measurement. Via the intuitive interface, lengths, angles, areas and perimeters can be directly measured in the live preview. The measured data can then be exported to any spreadsheet application via the CSV export function.
- Mark and annotate image features with IC Measure's annotation tools. Annotations are fully customizable in font, size and color.
- IC Measure features advanced image processing filters to correct for optical distortions (e.g. barrel and pincushion distortion) as well as image enhancement tools such as histogram equalization, sharpness, brightness and contrast.
- IC Measure's on-screen calibration tools, allow for efficient software calibration using a stage micrometer, graph paper or virtually any object of known size and can be used for measuring tasks outside of microscopy applications as well.
- All measured objects saved in IC Measure can be stored and used for future projects.
- All camera properties, such as video formats, and exposure times can be applied and set for future sessions.
- Single image frames can be captured from the live video stream and saved as a BMP, TIFF or JPEG file.
- A number of frames can be acquired and saved to a sequence of image files. The number of image frames, which are saved can be limited by either a specific number of by a time limit.
- On-screen measurement of lengths, angles, areas and perimeters.
- Export measured data to any spreadsheet application.
- Mark and annotate image features with annotation tools.
- Easy software calibration.
- IC Measure: Free software available for download.
The following file can be downloaded:
- IC Measure - Manual On-Screen Image Measurement and Image Acquisition
- IC Measure provides powerful tools for the manual measurement of circles, lines, polygons and angles. The convenient user interface enables the easy measurement of lengths, angles and surfaces directly from the image displayed on the monitor. Measurement data can be exported as CSV file.
Please contact support, if you need any assistance using the software.


PC Plastic Horizontal Fiber Optic Splice Closure Patch Panel For Aerial Hanger
Suitable for bunchy & ribbon fibers
Aerial, underground, wall-mounting, hand hole-mounting and duct-mounting
It’s especially applicable to FTTH optical fiber distribution
FOC (04) series fiber optic in-line closure provide suitable for cable whose diameter is 10-23mm, they could be used in aerial, duct, and direct buried application. These products are made of the high quality material and with the mechanical sealing structure filled with the sealing material. The external components and fastening parts are made of stainless steel. They could be opened and reused without changing sealing material.


DJI Zenmuse P1
Shop Zenmuse P1 Drone Cameras
Zenmuse P1 with low-noise high-sensitivity sensor
The Zenmuse P1 is a specialized aerial photography camera designed by DJI for professional and enterprise use. It features a low-noise, high-sensitivity sensor that captures ultra-clear images, making it particularly effective for precision mapping, surveying, and detailed inspection work. The P1's advanced capabilities ensure high-quality data collection for a variety of applications.
Key features of Zenmuse P1
The Zenmuse P1 stands out with several advanced features that enhance its utility in aerial imaging:
- Full-frame sensor: Delivers superior image quality, high resolution, and an extensive dynamic range.
- Low-noise performance: Guarantees detailed images in low-light conditions, increasing the camera's adaptability to different environments.
- Interchangeable lens compatibility: Allows for a wide range of photographic expressions and technical demands, offering users the flexibility to select the ideal lens for each project.
- Smart Oblique Capture: Seamlessly works with DJI's flight planning software for efficient data capture, essential for 3D modeling and mapping.
- High-precision mapping: Achieves accurate mapping results without the need for ground control points, streamlining surveying and mapping processes.
Applications of Zenmuse P1
The Zenmuse P1's sophisticated imaging technology supports a broad spectrum of applications across several industries:
- Precision surveying and mapping: Perfect for generating accurate 2D maps and 3D models in construction, urban planning, and land conservation.
- Infrastructure inspection: Provides detailed imagery for inspecting bridges, buildings, and energy infrastructures, aiding in maintenance and safety evaluations.
- Agricultural monitoring: Assists in precise crop health monitoring, contributing to improved agricultural management and practices.
- Environmental research: Facilitates detailed environmental studies and conservation efforts with high-quality imaging of ecosystems and natural landscapes.
Explore the capabilities of Zenmuse P1
The Zenmuse P1, with its low-noise, high-sensitivity sensor, offers unparalleled image clarity and precision for professional and enterprise aerial imaging needs. Whether your project involves mapping, inspection, or monitoring, the P1 is equipped to provide top-tier imagery and data.
Discover how the Zenmuse P1 can revolutionize your aerial imaging tasks. Contact us today for more information on this advanced imaging solution and how it can be integrated into your operations. Let the Zenmuse P1 elevate the quality and efficiency of your projects.


Based on laser rotary encoder technology and consisting of a specialized motor encoder and a controller, the KP1SM100 system is designed to precisely control laser beam scanning through high inertia mirrors. The new, ultra-compact encoder system is said to be particularly applicable for portable electronic devices and is expected to find wide use in various laser marking and processing applications, including high-density pc board manufacturing. It also has applications in laser trimmers, rapid prototyping equipment, and other high precision areas. The system features a high scanning angle (±10°) and rotor inertia (10.5 gcm-sq.) with a 30-mm diameter mirror, resulting in a positioning resolution of 0.02 arc-seconds or less. Torque constant is 0.10 Nm/A. The KP-1SM100 laser scanners achieve a positioning accuracy of 0.5 µrad or lower and accelerate to settling speeds of 0.7 ms/0.3° and settling range of ±215 µrad. For more information, contact Ron Travis at CANON U.S.A. INC., Semiconductor Division Encoder Products Group, Lake Success, NY. (516) 328-4611.
Company: CANON U.S.A. INC. - Semiconductor Division Encoder Products Group
Product URL: Click here for more information


Nick, I also just received an Olympus SP. Gonna try shooting with it this weekend.
I did try shooting the same scene with and without Skylight 1B with Elitechrome 100 film; a slide film. Guess what, since I didn't take note which shot was done with/without the filter, when I had the film developed about 2 weeks later, I couldn't tell the difference!
If you buy a good 1B or UV filter, you don't need to worry about ghost image when pointing the lens towards the sun or other bright light source. Here's a few of (aestheticaly bad) shots with Hoya HMC 1B attached. The second photo was shot without any lenshood at all.


Two developments in image sensor technology were announced this week which would fundamentally disrupt the photographic industry if they were to make it to commercial manufacture.
Sony, Canon and Nikon have been working on curved sensors for some time, but Microsoft Research has now developed a sensor with three times more curvature than previously achieved.
‘When using curved sensors, it is possible to correct aberrations in a much more efficient way, making it easier to create very wide-angle lenses that produce sharp images across the entire field of view or to create fast lenses that produce better images in low light,’ said Neel Joshi, a member of the Microsoft Research team. ‘It is also more straightforward to make cameras that exhibit uniform illumination across the entire image.’
Microsoft Research has built a camera using the sensor which the researchers say produced higher resolution images across the entire field of view when compared to modern high-end DSLR cameras.
‘We have created a prototype curved sensor camera with extraordinary performance. It surpasses, and in the case of illumination uniformity far exceeds, the performance of much larger professional camera systems like the Canon 1Ds DSLR equipped with a similarly fast f/1.2 50mm lens.’
Tests showed that curving the sensors did not change any of their electrical or imaging characteristics. When used in a prototype camera with a specially designed f/1.2 lens, the curved sensor had resolution more than double that of a high-end SLR camera with a similar lens. Toward the edges of the image, the curved sensor was about five times sharper than the SLR camera.
Meanwhile, over at Caltech (California Institute of Technology), researchers have developed a sensor which doesn’t even need a lens to capture images.
‘We’ve created a single thin layer of integrated silicon photonics that emulates the lens and sensor of a digital camera, reducing the thickness and cost of digital cameras,’ said Ali Hajimiri, the leader of the Caltech research team. ‘It can mimic a regular lens, but can switch from a fish-eye to a telephoto lens instantaneously—with just a simple adjustment in the way the array receives light.
‘The ability to control all the optical properties of a camera electronically using a paper-thin layer of low-cost silicon photonics without any mechanical movement, lenses, or mirrors, opens a new world of imagers that could look like wallpaper, blinds, or even wearable fabric,’ he said.
It’s early days yet, with the camera only capable of very low resolution images, but future applications could range from super thin cameras and smartphones through to huge ‘telescopes’ capable of imaging the universe.


With a host of brand new features designed to enhance every facet of the photographic process, from still images to video, the new EOS 7D represents a whole new class of camera.
Made to be the tool of choice for serious photographers and semi-professionals, the EOS 7D features an all-new 18.0 Megapixel APS-C size CMOS sensor and Dual DIGIC 4 Image Processors, capturing tremendous images at up to ISO 12800 and speeds of up to 8 fps. The EOS 7D has a new all cross-type 19-point AF system with improved AI Servo II AF subject tracking and user-selectable AF area selection modes for sharp focus no matter the situation. The EOS 7D's Intelligent Viewfinder, an entirely newly-designed technology, provides approximately 100% coverage and displays user-selected AF modes as well as a spot metering circle and on demand grid lines. New iFCL Metering with 63-zone dual-layer metering system uses both focus and color information to provide accurate exposure even in difficult lighting. The EOS 7D also captures Full HD video at 30p (29.97 fps), 24p (23.976 fps) and 25p with an array of manual controls, including manual exposure during movie shooting and ISO speed selection. The EOS 7D features a magnesium alloy body that is dust- and weather-resistant and shutter durability of up to 150,000 cycles. Compatible with over 60 EF and EF-S lenses as well as with EOS System accessories, the creative opportunities - not just with stills but also with video - are beyond amazement.
EF 28-135mm f/3.5-5.6 IS USM Lens
The Canon EF 28-135mm f/3.5-5.6 IS Lens is a compact and lightweight standard zoom lens that offers superior optical performance, plus a built-in Image Stabilizer. The IS system reduces the possibility of blurred photographs caused by camera shake, which allows for handheld photography in comparatively dim light without a flash or tripod. At the wideangle end of the zoom range, the equivalent shutter speed gain is approximately 1.5 stops while at the telephoto end, it is approximately 2 stops.
In addition, the lens has a USM drive mechanism for faster and quieter AF operation, and the pulse control diaphragm (EMD) ensures precise aperture control.
The IS system is composed of a pair of gyro sensors to detect vertical and horizontal motion and a microprocessor that compensates for it by shifting special lens elements in parallel with the perceived movement.
The internal focusing mechanism allows the front of the lens to remain stationary and to easily accommodate specialty filters, such as polarizing filters.
Maximum resolution for any application.
The EOS 7D features a Canon-designed 18.0 Megapixel APS-C size CMOS sensor that captures such a high level of resolution it's easy to crop images for enlargement without concern of losing detail. A major factor in reducing noise, the CMOS sensor assures that images shot at highest sensitivity will be remarkably smooth. Dual DIGIC 4 Image Processors ensure that images are captured, processed and saved with remarkable speed. The EOS 7D's ability to capture and process data of images shot at 18.0 Megapixels at 8 fps, as well as Face Detection Live Mode, Full HD video recording, Auto Lighting Optimizer and Lens Peripheral optimization are all possible thanks to the Dual
DIGIC 4 Image Processors.


A pinhole camera, a variation of Camera obscura, is a simple camera without a lens and with a single small aperture, a pinhole – effectively a light-proof box with a small hole in one side. Light from a scene passes through this single point and projects an inverted image on the opposite side of the box. Exposures can typically range from five seconds up to as much as several hours. The effect was noted in the 5th century BC in China and has been refined over the centuries.
A pinhole camera, also known as camera obscura, or "dark chamber", is a simple optical imaging device in the shape of a closed box or chamber. In one of its sides is a small hole which, via the rectilinear propagation of light, creates an image of the outside space on the opposite side of the box.
A pinhole camera is completely dark on all the other sides of the box including the side where the point is created. This part is usually painted black, but black boxes are also used for this purpose. There is also a thin screen which looks like a projector sheet, and is put in between the dark side adjacent to the pinhole.


Application of Hyperspectral Technology in Agriculture and Biology Industry
The current consumer electronics is moving towards more precise, and the development of 5G and Internet of Things has given a market demand for mobile phone multi-functional integration. Users will not be satisfied for only communications and entertainment. To promote the convenience of end-user is one of the tasks of technology development. From the perspective of UAV product from the consumer field, its multivariate application scenarios have used a variety of sensing / detecting chip systems and lens modules. Infrared technologies innovation and integration is making drones in mapping or fire safety systems more precise and effective. Foreseeably, future consumer electronics need to add more technological innovation. At present, the infrared industry is focused on how to accelerate the infrared industry technology into more civil markets.
Hyperspectral remote sensing technology is an emerging technology developed in the early 1980s and has become one of the hottest frontier topics in the field of remote sensing science. With high spectral resolution, hyperspectral technology can simultaneously obtain geometric and spectral characteristics of features, and realize fine classification of features and identification of material components. It has broad application prospects in agriculture and biological industries such as fine classification of vegetation and productivity assessment of soil organic matter content and fertility, crop growth and yield prediction, agricultural pest monitoring, ecosystem diversity and species community research. It has become a frontier technology that countries are competing to develop.
The current situation and trend analysis of hyperspectral imaging development is that satellite-borne hyperspectral technology was dominated by foreign countries before 2000, mainly experimental and scientific satellites, with low amplitude - spatial resolution ratio, and some spectral coverage only to the near-infrared band. Hyperion of the United States is a typical representative of satellite-borne hyperspectral imager. The advancement of China's satellite-borne hyperspectral technology is mainly dominated by the institutes of the Academy of Sciences, which started 5 to 10 years later than foreign countries. At present, China's satellite-borne hyperspectral technology has come to the forefront in the world. Compared with Hyperion, GF-5/AHSI has 8 times higher amplitude, nearly 100 more spectral channels, and nearly 4 times higher signal-to-noise ratio. Compared with current international hyperspectral imagers, the number of spectral bands has increased by nearly a hundred, and the width-spatial resolution ratio has nearly been doubled. Shanghai Institute of Technology of Chinese Academy of Sciences has broken through the key technologies of broad spectrum, wide range, high detection sensitivity, and high accuracy, and developed the first wide range and broad-spectrum satellite-borne hyperspectral imaging payload, which fills the gap of infrared hyperspectral data acquisition.
High-performance satellite-borne spectral cameras can play an important role in various industries, such as ecological environment, mineral resources, soil pollution, urban change, as well as monitoring fields like forestry, agriculture, and fishery.
Water pollution applications: very high spectral resolution, can be very clear detection of water quality of the physical situation. These applications have also been a very good evaluation in our ecological and environmental protection, and has reached the highest level of modern high light remote sensing.
Mineral resources: underground minerals can penetrate the surface later to identify the surface material and analyze the process of the evolution of the underground composition structure performance, which can well detect the detection of compounds of the earth's underground organisms. The development of hyperspectral technology is tantamount to spanning the search for minerals from the core to the surface.
Ecological system: The classification rate of hyperspectral is very strong, and the accuracy of hyperspectral classification to more than ten categories is still relatively high, to achieve "green mountains and water" for effective detection of the ecological system, classification is very important.
Gas emission monitoring: the current methane emissions are detected clearly; it has been able to detect 35 points through the U.S. airborne hyperspectral for carbon emissions.
Regarding the use of hyperspectral technology in agriculture, food security is the weight of the heavy, high spectroscopy can take responsibilities in the monitoring of crop species, auditations of agriculture, planting area monitoring, crops growing monitoring, pest control, soil fat monitoring, soil testing and so on. Fluorescence and crops are completely related to highly related similarities and have an important role in the early detection and prevention of land arid and crop pests and prevent significant losses. In addition, through the identification of the object type, the crop area is evaluated by the long-term detection or field sampling investigation units, and the rapid estimation of large-area crops can be achieved, and the agricultural activity management strategy can be arranged.
Let's learn more about the application of hyperspectral technology in biomedical field.
1. Diagnose the tissue disease state, at a specific wavelength, the chemical composition and physical characteristics of different pathological state tissues have different reflectance, absorbance and electromagnetic energy, which are manifested as differences in characteristic spectral peaks, through analyzing these spectral signals, qualitative or quantitative detection of tissue state information can be realized, and according to the spatial distribution information provided by hyperspectral images, visualization of different pathological states of tissues can be achieved. By analyzing these spectral signals, the qualitative or quantitative detection of tissue state information can be realized, and the visualization of different pathological states of tissues can be achieved based on the spatial distribution information provided by hyperspectral images, so as to achieve diagnostic results.
2. By obtaining different dimensional data of biological tissues such as space, spectrum and radiation, hyperspectral technology is used to obtain the real dynamic and comprehensive information of the measured objects, and then real-time dynamic processing and analysis are performed with the support of new models and algorithms, which is useful for exploring genes, biomolecules and cells from the molecular level. This has an important role in promoting the exploration of the life activities of genes, biomolecules and cells and their relationship with the mechanism of disease development at the molecular level.
3. Hyperspectral technology was used for the identification of lesion cells in acute lymphoblastic leukemia, and the recognition accuracy of lesion cells in acute lymphoblastic leukemia could reach more than 90%.
4. Spectral imaging technology was used for the identification of unstained nerves, and the initial classification of sensory and motor nerves was achieved.
5. In tumor detection, the imaging and identification speed of hyperspectral technology is much higher than that of conventional tumor medical imaging technology and is widely used.
Summary: In the field of hyperspectral imaging technology, many new principles, new schemes and new technologies are being implemented and applied, and the integrated acquisition and processing capability of multiple information has been greatly enhanced, and hyperspectral imaging is gradually developing in the direction of large field of view, large relative aperture, high resolution and high quantification. Meanwhile, with the continuous development and maturity of hyperspectral imaging technology, its cost will be greatly reduced, and its commercial application will be an important direction for future development. In the future, it will play a greater role in agriculture, biomedical and fluorescence detection.


Collapsible measuring magnifier Horizon with the 4x magnification is designed to explore and measure dimensions of small objects, as well as for small fonts. Compact folding design, size when folded 45х15х57 mm, diopter setting in the range of ± 1.2 diopters, the measuring grid with a scale division of 2 mm, linear field of vision of the 32x32 mm, weight 0,039 kg of Russian production of JSC "Krasnogorsk plant them. S. A. Zvereva" (Zenit).
Measuring magnifier with 8-fold magnification is intended for examining fine details, objects that require high magnification. Diopter setting of ± 3,2 diopters, the minimum interval is 1 mm, the scale for measuring the reporting of details/objects, the dividing mesh to estimate the magnitude of the subject. Dimensions folded - 47х47х53 mm Weight 82 grams. Manufacturer JSC "Krasnogorsky Zavod im. S. A. Zvereva", Russia.
Measuring magnifier Horizon 10x optical tool for fine detail work. With optical magnifiers can also determine the size of objects. Pitch grid and scale for assessing the extent and measurement of details to consider. Diopter setting of ± 4,5 diopters, minimal graduation 0.1 mm, dimensions 49х44 mm, weight: 0,112 kg of Production of JSC "Krasnogorsk plant them. S. A. Zvereva" (Zenit), Russia.
Magnifier measurement LI-2-8x designed to measure the linear dimensions of small objects, ranging from 0.1 to 10mm. Measurement accuracy down to 0.1 mm Diopter setting of ± 5 diopters, the price of division of the measuring scales: 0.1 mm on a light background with opaque strokes, 0.5 mm on a dark background with transparent strokes, focal length 31 mm. package dimensions - 36х36х55,5 mm. Weight 0,04 kg Robust metal housing. The optical loupe has passed the state acceptance tests. Loupe LI-2-8x comes with a state verification and included in the State register of measuring RF. Manufacturer - JSC "BelOMO - Minsk mechanical plant named after S. I. Vavilov".
Loupe PL 2 is an optical magnifying instrument for examining small items, parts, tools, fonts, coins, study cards and so on. Optical zoom – 2 times. Focal length 205 mm, light lens diameter 56 mm lens Material – optical glass. The material of the rim and the handle - resin. Dimensions 176х67х10 mm Weight 0,06 kg.
Loupe PL - 4 is used for examining small parts, studying maps, reading small fonts, and the like. The optical zoom is 4x. Focal length 102 mm luminous diameter of the lens 56 mm. Made in the frame with the handle of a polymeric material. Lens material – optical polymer, anti-static coating. Dimensions 177х67х19 mm. Weight kg 0,052


To achieve a CIE color coordinate target with LEDs requires mixing accurate light amounts from the LED sources and knowledge of the precise color that an LED will generate under the given excitation and ambient conditions.
The requirements for accurate color illumination with LEDs are derived from the sensitivity of human color vision. Human vision translates color by the ratio of red, green, and blue cone simulation. The red, green, and blue cones do not only respond to red, green, and blue light. There is continuous overlap in cone excitation. The red cone is excited at some level from deep red through blue, the green cone is stimulated by red-orange through blue-violet, and the blue cone is stimulated by yellow-green to deep violet. The total of all three cone stimulation amounts follows a smooth bell curve that peaks at green. The sensitivity of the eye to color differences depends on how much the cone stimulation ratio changes in that area of color. The eye is most sensitive around the area of warm whites and least sensitive in the saturated green area. A green mix that has a 5% error in the amount of light coming from the green source may not look off target but a warm white mix with that amount of error would be obviously off target.
Human brightness perception is also helpful to understand. Like many other senses brightness perception is not linear. For a perceived doubling of light intensity the number light light photons coming from the source must increase by much more than double. An easy approximation mathematically is the use the square so that a perceived doubling requires a four times increase in the source photon emission. If this is translated into dimming, achieving a perceived 10% dimming level from full brightness requires the source to emit 1% of the photons that it does at full intensity.
To design a precise color illumination system it is necessary to understand how an LED behaves. LEDs do not make light photons at any current level. There is a minimum current at which the LED will make photons and around this level the color of the light of the LED changes a lot making it difficult to compensate for. This level is typically below 1% of the maximum LED current. When operated above the minimum current level the LED’s color shifts with the current and operating temperature an amount that is dependent on the LED’s color. Some red LEDs change in intensity by a factor of two as the operating temperature changes from minimum to maximum. Some Green LEDs change in color several perceptible steps as the operating temperature changes. All LEDs decrease in efficiency as the current increases.
To generate an accurate color illuminant from LED sources an LED drive level is calculated based upon the LEDs’ intensity and color characteristics over the operating temperature and current levels. Some of these characteristics like color drift are consistent enough for a particular LED that the same data can be used for all fixtures if the color accuracy requirement isn’t too great. Other characteristics like LED intensity can change more between parts or lots of parts. This data would need to be collected for each fixture produced as a calibration step in the production process. If the color accuracy requirement is sufficiently loose calibration wouldn’t be necessary.


… ”Most chosen fiber laser machine for schools and SMEs”….
Powerful shop fiber laser
With a fiber laser size 130 x 90 cm. you can effortlessly cut through metals such as steel, stainless steel (inox), copper, titanium and aluminum with high speed and ultra precision. The fiber laser is extremely powerful and consumes very little power. These machines are available in different powers from 1.000 to 4.000 Watt and cut up to 20 mm. thick steel.
… “powerful, easy and compact metal laser for every workshop” …
intelligent PRE-Crash detection
When cutting loose shapes, the object sometimes rises or tilts, which can cause a crash with the laser head. No problem for the automatic control. The Raytools cutting head with built-in intelligence sees a crash hazard well in advance and automatically stops before accidents happen. The laser head moves to a safe position, and the traffic light on the machine signals the machine operator to straighten or remove the tilted material.
automatic ventilation monitoring
When cutting metals you sometimes use pure oxygen. Oxygen is a good oxidizer but can also be explosive under certain circumstances. Irritating fumes are also produced during the cutting process. This machine must therefore be equipped with: a ventilation monitoring system which automatically blocks the laser if no air extraction is measured in the machine. Our consultation service will help you with this.
… ”Standard built-in support using artificial intelligence”…
computer controlled cooling tower
Cooling is very important for your fiber laser, so a very high-quality fully automatic cooling machine with 2 separate cooling circuits is a must. This means that the laser source and the laser head with the lenses are kept separately and very precisely at their own temperature.
The cooling towers are fully pre-programmed and pre-installed and are operational within 10 minutes. Naturally, the cooling tower communicates directly with the laser machine. In the event of an alarm, the cooling machine will immediately switch off the laser source to prevent damage to the laser.
remote control system
These fiber lasers come with radio remote control for quick and easy positioning in
You will soon notice that you can work much more efficiently and precisely with the remote control and you will never want to be without it again. The remote control is magnetic and can be placed anywhere on the machine.
… “Very complete with all conceivable options included”…
Intelligent laser head with “pre-sense” technology
Material blocking the laser path? Cut pieces that flip up? Plates that are not flat? No problem at all with the standard built-in automatic Swiss Raytools cutting head which measures where it is in relation to the material thousands of times per second. If the material is warped or warped, the Raytools head effortlessly follows the material to an accuracy of 0,003 mm. With our consultation we direct you to the right products.
automatic plate-edge detection
With the built-in BCS100 system it is also possible to have the edges of the sheet material searched fully automatically and the software to automatically compensate for skewed plates. Never askew again cut objects or cut next to the plate.
Finally, these systems are equipped with extensive self-monitoring and self-calibration, so that the system fully adjusts and adjusts itself automatically.
… ”Robustly built for 24/7 production 365 days a year”…
very extensive software including training
Fiber lasers are often supplied as standard with the very powerful CYPCUT controller system for programming your cutting orders. Cypcut is intuitive enough to get started right away, but has many professional features that you would normally have to purchase separately, already built in as standard. So has cypcut automatic nesting functions to efficiently organize plates, extensive lead in / out options, micro joints, fly cutting , pierce functions and extensive cutting settings. Of course you can directly control almost all possibilities of the fiber laser from cypcut. For example, you can control the entire CNC system, regulate gas types and pressures, control the laser source remotely and possibly take over a BCS100 system.
Our consultation service includes training!
computer controlled solid state laser source
Naturally, the laser source is the heart of the fiber laser machine and of course you only choose the best of the best. We recommend the Raycus fiber laser sources as standard. These systems are very stable and have a MTBF of up to 80.000 hours. Optionally, the machine can also be equipped with an IPG laser source for highly reflective materials. These brands are at the top of the fiber laser market.
The laser source itself is completely solid-state, so no moving parts and completely maintenance free. The powerful built-in computers fine-tune the pulse frequencies, pulse lengths and power curves.
Wireless control & integrated Hi-Res control panel
The operation of these machines is very simple and runs on built-in as standard windows OS operating system and the very powerful cypcut controller system. Everything can be set up and started clearly and intuitively via the wireless keyboard, mouse and handheld.
complete installation and on-site training
Fiber lasers are extremely complex and must of course be precisely programmed and calibrated during installation. We can point you to the right technicians and rely on years of local expertise.
We provide training for this complex hardware in the language you prefer, in the language of your choice Dutch, English, German or French.
… “The cheapest fiber lasers in Europe and yet with all options included”…
For this machine we strongly recommend using a HEPA filter installation that cleans and recirculates the air. Healthier working air, cheaper work and no environmental permit required (as may be the case with blowing outside)


Introducing a truly amazing new compact HDV camcorder from Sony. The HVR-Z5U camcorder is designed to enhance creativity and deliver the highest standard of optical and audio quality. Sony's newly designed "G Lens" is incorporated into the camcorder, boasting excellent resolution, color, and contrast for breathtaking images that rival expensive interchangeable lenses. This new compact camcorder boasts Sony's 3 ClearVid CMOS Sensor system, utilizing the technology of Exmor, to provide excellent low-light sensitivity and making it ideal when high performance in limited light conditions is a requirement. The ergonomically designed body allows flexible shooting under any conditions, while maintaining Sony's worldwide reputation for quality and high performance. The standard features of the HVR-Z5U include 1080/24p/30p HDV native progressive recording modes. Sony's new cutting-edge hybrid recording system incorporates an optional HVR-DR60 or HVR-MRC1K Memory Recording Unit, which allows simultaneous recording on tape and non-tape media for improve NLE workflow efficiency. The hybrid recording system is also capable of simultaneous HD and SD recording. Sony is continuously developing and expanding its HDV lineup in response to professional user feedback.
- Sony's Exclusive High-performance "G Lens"
- Natural-touch Lens Operation
- Ideal Handheld Camcorder Design
- 1/3 inch-type 3 ClearVid CMOS Sensor System
- Enchanced Functionality with Exmor Technology
- Ready for HYBRID Solution with the optional HVR-MRC1K


The Claypaky Stormy uses the latest LED technology, but retains all the charm of a classic strobe. The light source is a strip of powerful white LEDs, which perfectly emulates a bright Xenon linear lamp.
The flash effect is enhanced as the Stormy is equipped with a parabolic reflector, just like a classic strobe, and does not project the light directly forwards like other LED strobes do. The frequency, duration and intensity of the pulse are digitally controlled, and these parameters are independently adjustable.
Thanks to its highly sophisticated electronics, the light turns on and off instantly, creating the jerky movement illusion. The time the light is on (the pulse duration) may be extended as required. Thanks to it being an LED strobe, the light intensity remains absolutely constant without a flickering effect.
- Perfect emulation of a bright Xenon strobe linear lamp
- Beam opening control by optional barndoors
- Total brightness: – 80,000 lm
- DMX 512 control channels: 3
- 0-100% adjustable dimmer
- Strobe pulse duration
- Strobe pulse rate
- Bracket adjustable on 360°
- Remote Device Management (RDM)


Marine animals have several adaptations to their eyes, including different muscle arrangements, tissues of more similar density to the surrounding water and a more spherical lens than humans. The precise mechanism varies with species, however, with otters apparently relying more on muscles around the eye distorting the lens to focus, while whales have an eye so similar in density to seawater that very little focusing it necessary. Human eyes have evolved to bend light considerably to accommodate the much greater density of our eyes relative to the surrounding air – when underwater, this “over-bending” results in us being extremely long-sighted and everything looking blurred unless we add a layer of air in front of our eyes with the aid of goggles.
Humans can see underwater, we just have difficulty focusing – hence objects appear blurred when viewed underwater without the aid of a scuba mask or goggles. Water is about 800 times denser than air and, as a result, light travels more slowly in it. Indeed, light travels almost 23% slower in water than it does in air, which represents a reduction in speed of approximately 66,000 kilometres per second (or about 41,000 miles per second).
The cornea of the human eye is also more dense than air and this causes light to be refracted (bent) as it passes through the pupil. This light is then ‘bent’ again by the lens to focus it onto the retina. Special ciliary muscles in the eye tighten and relax, distorting the shape of the lens to focus the image. When the light hits the rods and cones—special light-sensitive cells on the retina—they ‘fire’, sending messages to the brain via the optic nerve. Under ‘normal’ circumstances, light passes from a gas (air) into a liquid (the vitreous humour in the eyeball), but the situation is reversed underwater. The substantial difference in density between the water and the cornea causes the human eye to lose most of its refractive power; the lens is unable to compensate for this and the image appears out of focus.
The inability of our lens to accommodate this difference in refraction makes us acutely hyperopic, or long-sighted, underwater and objects appear blurred. Indeed, at distances more than five metres (about 16ft), humans are almost incapable of deciphering an object from the background underwater. Overcoming this problem requires a layer of air to be present in front of the eyeball (i.e. trapped by a scuba mask or goggles). This is not without its problems, though. If you imagine that our ray of light is happily travelling towards you at about 225,000 km per second (140,000 miles per second), suddenly it enters your scuba mask and accelerates to about 290,000 km per second (181,000 miles per second). This change of speed as the light passes from the water into the airspace of your mask causes its angle to shift slightly – this shift results in objects appearing about 25% bigger than they really are.
Fish obviously don't wear goggles, so how do they manage? Well, they have evolved to see things in the underwater world with the help of a larger, more spherical lens than land vertebrates. Additionally, there is very little difference in density between the fish cornea and that of the seawater, so there is very little refraction and focusing is left up to the lens. It is commonly considered that marine mammals can see equally well above and below the waterline. The mechanisms for this ‘dual-fluid’ vision are, however, largely speculative.
A study by Ronald Schusterman and Barry Barrett in 1973 revealed some interesting insights into the visual system of the Asian short-clawed otter (Aonyx cinerea). Schusterman and Barrett designed a series of experiments to test the otters’ visual acuity (i.e. how well the otters could decipher fine detail) in air and underwater at different light levels. They found that the otters had almost equal visual acuity in water and air under conditions of bright light, but their underwater vision was poorer than their vision in air under conditions of dim light. Schusterman and Barrett considered that otters probably have a similar focusing mechanism to turtles, in that the front of the lens is squeezed by muscles around the iris. Hence, they suggest that poor underwater vision in the dark might be a result of pupil dilation leading to an insufficient squeezing of the lens. In terms of optical morphology, the otter uses a similar method of maintaining visual acuity as fish (i.e. the lens is more spherical so that it can compensate for the different refractive index of water).
In whales, the difference in refractive index between the cornea and seawater is slight, much less than it is in humans, so there is little focusing taking place at the water-cornea interface. Some evidence also indicates that many whales lack interocular (between eyes) muscles, suggesting that focusing is either less important or accomplished differently. Dolphins apparently have eyes more similar to fish than humans – the lens is greatly increased, almost spherical in shape and situated further forward in the eye. According to chairman of the Information Committee of the European Association for Aquatic Mammals, Jaap van der Toorn, the dolphin retina is “organized differently than most mammal eyes”, having two yellow spots. Yellow spots, also known as foveas, are areas of high sensitivity and the human eye only has one. van der Toorn suggests that one spot is probably associated with forward vision, the other with lateral vision.
Interestingly, a similar structure was observed on the retina of the great white shark (Carcharodon carcharias) by Samuel Gruber and Joel Cohen in their 1985 paper; it's thought that it may increase the sharks’ visual acuity in poor light conditions, especially at dawn and dusk. van der Toorn also notes that the dolphin pupil has a covering that can slide over it in conditions of bright light, possibly giving the dolphin a greater depth-of-field above water.
A paper to the journal Cetology during 1972 reported that dolphins are myopic, or short sighted, in air. In the paper, William Dawson and his colleagues suggest that the aerial acuity in bottlenose dolphins (Tursiops truncatus) may be equal to their underwater acuity because they have a pupil that becomes tightly constricted in bright light (i.e. in air) compared to water. Several studies on dolphin vision have suggested that in water (and possibly air) dolphins were emmetropic (i.e. focused at infinity).
In an intriguing paper published in the journal Marine Mammal Science back in 2001, Thomas Cronin and Tricia Litwiler attempted to identify the mechanism by which dolphin eyes were able to adjust to focus on objects at various distances. Their measurements of the refractive state of the dolphin’s eyes in water revealed that two individuals were indeed emmertrophic, while a third was slightly myopic. Interestingly, Cronin and Litwiler found no evidence for accommodation in any of the subjects examined. The authors propose that underwater vision may be used merely to supplement echolocation and, as such, the ability to focus sharply may not be necessary.
A study looking at pinnipeds (seals and sea lions) found a similar response to that described by Schusterman and Barrett in otters. In his 1970 paper to the journal Science, Ronald Schusterman found that, in the Californian sea lion (Zalophus californianus), only when luminance levels were reasonably high (in the range of 100 to 200 mL) were the sea lions able to resolve detail equally well in air and underwater.
In conclusion, it seems that there has been a degree of convergent evolution of the eye in marine species, leading to a scenario where the lens is larger and more spherical in shape to compensate for the loss of corneal focusing input. It is often difficult for us, a species for whom vision is such a crucial sense, to comprehend how animals could perform in a blurry world. When you watch aquatic predators hunting, however, it becomes apparent that the ability to focus a pin-sharp image is much less important to them than it is to us - otters feel for their prey, dolphins echolocate, whale sharks may ‘sniff out’ microscopic plankton, and so forth.