If you are in the market for hunting binoculars then we hope that you will find that this Bushnell Green Roof Trophy Binoculars 10×42 review will provide you with all of the key information that you need to decide whether they are right for you or not.
It can be really tough to find a hunting binocular that is tough enough for the job with quality optics which provide brightness and clarity without spending a lot of money. The Bushnell Green Roof Trophy Binoculars 10×42 certainly perform well and you should consider them seriously as your next set of hunting binoculars.
Bushnell have a very good reputation for producing some of the highest quality binoculars for hunters over the years. They have the toughness and durability that hunters demand as well as delivering high powered performance.
The 10 times 42 millimeter objective lens size and magnification factor has proved to be very popular and Bushnell fans all like the Michael Waddell Bone Collector edition on these fog proof and waterproof binoculars that have fast focus.
Michael Waddell is a well known hunter who stars in the Outdoor Channel show “Bone Collector”. He has many fans and is a very experienced hunter who has given his name to these Bushnell Green binoculars.
Features of the Bushnell Green Roof Trophy Binoculars 10×42
The optics on the Bushnell Green Roof Trophy Binoculars 10×42 are multi coated which helps to provide a very sharp image which is very bright. The magnification is ideal for providing high levels of clarity with very efficient transmission of light.
The focus is good too and delivers the kind of performance that need for hunting and viewing wildlife. You will be able to see clearly over long distances and moving objects are in sharp focus.
A BAK4 roof prism system is used and the prisms are also multi coated. This leads to images that are very clear and bright so you will be able to focus in on all of the details. It doesn’t matter if wildlife is on the move as the optics of the Bushnell Green Roof Trophy Binoculars 10×42 always deliver sharp images.
A lot of very expensive binoculars use the roof prism system as it provides a more “straight line” light travel experience than some porro systems do. The roof prisms are also more lightweight than the porro prisms so you are getting very high quality prisms here for the money.
The close focus distance on these binoculars is 8.2 feet and the field of view is an impressive 325 feet at 1000 yards. The eye relief is good at 15.2 millimeters and the exit pupil is 4.2 millimeters. These binoculars weigh just 25 ounces and the dimensions are 7 inches by 6 inches by 3 inches.
The Bushnell Green Roof Trophy Binoculars 10×42 has a center focusing wheel which enables you to focus your eyes with the optical plane and receive very sharp images. There is a diopter adjustment on one side of the focus wheel and this has a plus and minus sign either side of the zero position. You can remember your preferred settings for future use.
Ergonomics and Design
The Bushnell Green Roof Trophy Binoculars 10×42 are coated with an armor which is omnificent and consists of dura grip rubber. There is a soft touch thumb grip and overall the handling of these binoculars is very good.
The binoculars are both fog proof and water proof thanks to the nitrogen purged lenses and O ring seals that fit very well. You can use the binoculars without any difficulty in wet weather and also in locations with high humidity.
The eye lenses have a coating of rubber for additional comfort. The objective lenses have a handy flip cover and these binoculars come with a tripod adapter. Bushnell offer a lifetime warranty with these binoculars.
Bushnell Green Roof Trophy Binoculars 10×42 Pros
- Ideal magnification and objective lens size for hunting
- Impressive field of view
- Bone Collector Edition approved by Michael Waddell
- Very easy to use zoom feature which always delivers clear images
- Good build quality and highly durable
- Comfortable ergonomic design
- Fog proof and water proof
Bushnell Green Roof Trophy Binoculars 10×42 Cons
- Some people may find these binoculars a little bulky and heavy especially when used for long periods
- Sometimes lens cover falls off
Check out the latest prices for the Bushnell Green Roof Trophy Binoculars 10×42
The view of the Customers
The bushnell green roof trophy binocular 10×42 is highly rated by the customers. They were satisfied with the functioning of this binocular. Below are some of the things mentioned by the customers.
Better than binoculars that cost twice the price– these binoculars performed better than those purchased before at over twice the price. The weight and size are good and the magnification power is just right.
No regrets buying these binoculars– they provide a really great view and everything is visible. In a brush and desert setting it can be hard to see wildlife but these made everything clear.
Crystal clear optics– these are great binoculars to use and there is no color distortion or fuzziness. The fast focusing is very good and it locks in well. They are robust and well made which is evident when they are held. Well worth the money!
No fogging– Colorado in the winter was a good test for these binoculars. There was no fogging at any time despite the extreme weather conditions. Long distance viewing possible with the magnification power. These are really awesome binoculars at a great price.
Used these for whale watching– these are great binoculars for whale watching. The focus is good but not as accurate as with military glasses but this is not a problem.
No problems for glasses wearers– it is easy to use these binoculars with eye glasses and there are no problems like with other models when wearing glasses.
Comparable to higher spec binoculars– the brightness and clarity that these binoculars deliver is directly comparable to those that are in a much higher price bracket. Direct comparisons have been made to substantiate this claim.
Worth more than the price– For users involved in hunting it really is rare to find a product like this that is worth more than the asking price. A clear image is established without a lot of turning of the focus wheel. The eye relief is very good and they are really great to hold.
They fit large hands– Customers with bigger built find this binocular fit really well in their large hands and the image is so clear. Really fast focus and good design.
Our Verdict on the Bushnell Green Roof Trophy Binoculars 10×42
It is no surprise that these hunting binoculars have become best sellers. They are high quality and very durable offered at a low price. The clarity of the image produced by these binoculars is amazing which is due to the superior quality optics used.
Bushnell Green have taken care of the ergonomics well and these glasses are comfortable even after long periods of use. The armor provides a really nice grip and the eyecups are well cushioned. We highly recommend the Bushnell Green Roof Trophy Binoculars 10×42.


A lens flare is the result of light scattering within the camera’s lens. The flare can present itself as haze or as a pattern of artifacts. Here, you can add this artifact to add greater depth and dimension to the image.
Enter the Lens Flare mode via the Viewer Modes.
Double-click in the Viewer to add a Lens Flare to a light source. Once you do this you’ll see the Lens Flare icon and its properties will open. A red icon means the lens flare is active, while a blue icon means it is not active.
✭ Copy and paste lens flares by right-clicking in the viewer with a lens flare active, and then choose Copy Active Media Element. Right-click anywhere in the panorama and select Paste Media Element to paste. You can also copy and paste lens flares in the List View panel.


We offer only the Finest in Machine Tool Measurement. We can provide you with Heidenhain and Acu-Rite Linear Scales, Rotary Encoders, and Digital Displays.
Utilizing Heidenhain's Evaluation Electronics for Metrology, we offer the perfect solution for your hard gauging needs.
Acu-Rite's Magnification Checker aids in the calibration of optical comparator and other inspection equipment. The "Mag checker" is backed by Acu-Rite's years of expertise in glass scale technology.


If your car does not have an LCD screen or a rearview camera, you can install a rearview mirror connected to a rearview camera. Some mirrors coupled to a camera are even multifunctional, allowing you to use various applications. We tell you everything about the rearview camera mirror in this article!
Rearview mirror reversing camera: characteristics
The reversing camera mirror is an accessory that can be installed on a vehicle in order to look directly into the interior mirror during reversing manoeuvres, rather than on a screen installed lower than the driver’s usual field of vision.
More precisely, it is a rear view mirror in which an LCD screen is integrated or an LCD screen in the form of a rearview mirror. In this case, it is mounted on a mirror frame and coupled to a reversing camera installed at the rear of the vehicle.
Its characteristics are as follows:
It can be attached by clips to the already existing interior mirror, or replace it if it is a type of LCD mirror provided for this purpose, which can be glued to the windshield instead of the original model.
It works thanks to a WiFi transceiver.
The panoramic viewing angle in the rearview mirror is between 120 and 170°. Different coloured limits indicate to the driver the distance and the risk of collision with what is behind, the latter system being disengage able.
The reversing camera mirror can, using a memory card, record photos or videos taken by the camera.
Some models can even replace the LCD screen of a touchscreen car radio. They offer the possibility of controlling the car radio, GPS, web navigation and many existing computer applications.
The reversing camera supplied with the mirror is installed on the rear license plate holder.
The device can also have a front camera and a buffer battery powered by a charger connected to the cigarette lighter or to a power outlet allowing it to have an independent power supply if it has a detection function of movements. This automatically records what passes in front of the objectives of the two cameras as well as during an impact while the vehicle is parked, starting or braking.
Reversing camera mirror operation
This device is powered by a cable and a plug for mains, cigarette lighter or USB DC 12 V for the car. When the reversing camera rearview mirror offers various functions and applications, they are operated by a touch pen.
It starts automatically when the car is in motion or permanent with the buffer battery when it exists and is connected.
Features of the reversing camera mirror
The main advantages of this accessory are:
- Allowing you to guide you in reverse by simply looking in your rearview mirror, with the display of colour guides on the screen. This saves you the trouble of physically twisting to see where you are going through your vehicle’s rear window or having to use the side mirrors on a utility vehicle.
- The reversing camera mirror eliminates blind spots. It allows you to better see pedestrians and cyclists, or young children who can pass quickly behind your car without being able to see them without this accessory. He can therefore prevent you from hitting someone.
The comfort in manoeuvring offered by the reversing camera mirror means that you will not be able to do without it. If the system breaks down, or you use a car that is not equipped with it, you will lose your usual bearings and reflexes and will have to readjust to manoeuvring.


What is 3d-anaglyph? Anaglyph images are used to provide a stereoscopic 3D effect, when viewed with glasses where the two lenses are different (usually chromatically opposite) colors, such as red and cyan. Images are made up of two color layers, superimposed, but offset with respect to each other to produce a depth effect. So in this tutorial we will learn how to make a realistic 3D-Anaglyphic render in Maya 2012.
Note: click the 'Monitor' icon to view tutorial in full-screen HD.
Quick Guide for 3D-Anaglyph
What is 3d-anaglyph?
Anaglyph images are used to provide a stereoscopic 3D effect, when viewed with glasses where the two lenses are different (usually chromatically opposite) colors, such as red and cyan. Images are made up of two color layers, superimposed, but offset with respect to each other to produce a depth effect. Usually the main subject is in the center, while the foreground and background are shifted laterally in opposite directions. The picture contains two differently filtered colored images, one for each eye. When viewed through the "color coded" "anaglyph glasses", they reveal an integrated stereoscopic image. The visual cortex of the brain fuses this into perception of a three dimensional scene or composition.
How 3d-anaglyph works?
Viewing anaglyphs through appropriately colored glasses results in each eye seeing a slightly different picture. In a red-blue anaglyph, for instance, the eye covered by the red filter sees the red parts of the image as "white", and the blue parts as "black" (with the brain providing some adaption for color); the eye covered by the blue filter perceives the opposite effect. True white or true black areas are perceived the same by each eye. The brain blends together the image it receives from each eye, and interprets the differences as being the result of different distances. This creates a normal stereograph image without requiring the viewer to cross his or her eyes.
How to view a Stereoscopic Image?
A pair of eyeglasses with two filters of the same colors, once used on the cameras (or now simulated by image processing software manipulations) is worn by the viewer. In the case above, the red lens over the left eye allows only the red part of the anaglyph image through to that eye, while the cyan (blue/green) lens over the right eye allows only the blue and green parts of the image through to that eye. Portions of the image that are red will appear dark through the cyan filter, while portions of colors composed only of green and blue will appear dark through the red filter. Each eye therefore sees only the perspective it is supposed to see.
That's all folks.
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Dr. M. Ronan Conlon was lucky enough to begin his career in ophthalmology in tandem with the pioneering of refractive eye surgery in Canada. To bring laser eye surgery to Canada, Dr. Conlon and his colleagues had to first bring a laser. In 1996, this meant travelling to Germany, where the laser technology had been developed, and bringing a laser home. Taking initiative meant laser eye surgery was actually brought to Canada before it was available in the United States. As Dr. Conlon’s career, and with it, the Conlon Eye Institute, has grown, so has the laser technology. Dr. Conlon advanced his surgical skills while performing LASIK in Saskatoon as it moved from its early stages to the advanced procedure we have today. Dr. Conlon also transitioned to treating cataract patients, moving from cataract removal, to cutting edge lenses for visual enhancement at the highest level. Dr. Conlon is grateful for his place in a field that is constantly revolutionizing, allowing him to continually grow as well. He is proud to see how far ophthalmology has come, and with over 20,000 refractive procedures under his belt, is excited for the Conlon Eye Institute to continue serving patients as we journey to wherever it goes next.


The Olympus M.Zuiko 12-45mm f/4 Pro holds an impressive distinction: it is the world’s smallest and most lightweight fixed aperture standard zoom lens (in equivalent 35mm terms, this is a 24-90mm lens).
To put that into perspective, its 254g weight is about the same as a large apple – and its compact 70mm length (and 63.4mm diameter) is actually smaller. So Olympus has achieved an incredible feat of a truly pocketable constant aperture standard zoom – and one that is even capable of macro photography.
Like many standard zooms, the Olympus M.Zuiko 12-45mm f/4 Pro is the smaller and slower alternative to a faster lens in the family – in this case, the The Olympus M.Zuiko 12-40mm f/2.8 Pro. So this begs the question, which lens offers better bang for your buck – and which one is more suited to your specific shooting needs?
Mount: Micro Four Thirds
Lens construction: 12 elements in 9 groups
Angle of view: 84° (wide) / 27° (telephoto)
Diaphragm blades: 7
Minimum aperture: f/22
Minimum focusing distance: 0.12 m (wide) / 0.23 m (telephoto)
Maximum magnification ratio: 0.25x (0.5x 35mm equivalent)
Filter size: 58mm
Dimensions: 63.4 (dia) x 70mm (length)
Obviously the big selling point of the Olympus M.Zuiko 12-45mm f/4 Pro is its size. This feat of engineering is only possible on the Micro Four Thirds format, given the smaller sensor which requires smaller lenses; other APS-C or even full-frame camera bodies can be impressively small, the lenses remain significantly large, meaning that they don’t truly offer a complete compact package.
If you’re looking for a supremely small and light all-purpose, all-weather setup, mounting this lens on the Olympus OM-D E-M5 Mark III is a great combination that simply can’t be beaten on other camera systems.
Its Pro designation means that not only does it feature superior all-metal construction, and remarkable durability for such a lightweight optic, it is fully weather sealed to withstand water, dirt and freezing temperatures – so you only have to stop shooting when you’re good and ready.
The 12-45mm f/4 Pro is also a capable macro shooter, able to focus as close as 12cm at the widest end and 23cm at the telephoto, and offering 0.25x maximum magnification (0.5x equivalent, in full-frame terms) across the zoom range.
BUILD AND HANDLING
As noted, since it carries the Pro suffix, the 12-45mm f/4 is a brilliantly built lens, every bit as sturdy and substantial as its bigger f/2.8 brother. Despite its lightness, it feels remarkably solid and will withstand plenty of knocks when shooting in the field. As a Pro lens it is also weather sealed, and thus makes a perfect partner for bodies like the Olympus OM-D E-M1 Mark III or E-M5 Mark III.
In everything from looks to handling to build quality, it is incredibly similar to the 12-40mm f/2.8 Pro – almost as if the larger lens was simply shrunk in the wash. So if you’re familiar with its sibling, you’ll be right at home here.
There are, however, some distinct differences in functionality. The biggest difference is that the 12-45mm f/4 Pro doesn’t possess the manual focus clutch (and, thus, nor the distance gauge), so you cannot quickly ‘pop’ it into manual focus on the fly. Likewise it omits the L-Fn function button, so it’s a very straightforward lens to operate – though one that is, arguably, lacking the inputs required of a pro optic.
Olympus wasn’t kidding when it said this lens is sharp across the entire zoom range; we’ve used sharper Oly glass, certainly, but performance across this range is impressive indeed – especially when shooting macro. Its autofocus is fast and accurate, too, and in all respects this is an excellent performer within its capabilities. It’s very hard to fault the 12-45mm f/4 Pro for what it does.
However, it isn’t quite so hard to fault the 12-45mm f/4 Pro for what it doesn’t. That f/4 aperture might keep the lens nice and light, but it does rather restrict your ability to take pristine shots in subpar light. For their many advantages, Micro Four Thirds sensors still aren’t at their best when ISOs are pushed; while the E-M5 Mark III and E-M1 Mark III can tolerate higher sensitivities much better than their predecessors, this can still lead to muddy images on the older Mark IIs or the Olympus OM-D E-M10 Mark III.
If you usually photograph somewhere with abundant natural light, or if you shoot in a studio or mobile setup with supplemental light, this won’t be a problem. However, a standard zoom is intended as a walkabout lens – which means that, sooner or later, you’ll need to start stretching your shutter speed.
Olympus’ rock-solid in-body image stabilization does a great job of facilitating this, though an f/4 lens would certainly have benefitted from the Sync IS technology (which significantly amplifies the in-body image stabilization of Olympus bodies) found in other Pro lenses. Of course, if you’re a landscape photographer or a shooter of static scenes using a tripod, this point is moot.
The f/4 aperture does mean that you are limited in the achievable shallowness of depth of field. Micro Four Thirds’ 2x crop factor effectively turns that f/4 into an f/8, in 35mm terms, meaning that you won’t be able to achieve much background blur even shooting at the 90mm equivalent telephoto extreme. That said, the bokeh rendition is very pleasing.
Conversely, that f/4 aperture can also work to your advantage. That same crop factor actually makes this the street photography lens that Weegee dreamed of; you still have the benefit of the f/4 aperture in terms of the amount of light gathered, but you can also exploit the equivalent “f/8 and be there” depth of field – making this a formidable street shooter, under appropriate conditions.
Likewise, the increased depth of field also comes into its own for macro photography. While the dedicated Olympus 60mm f/2.8 Macro is superior in this regard, the 12-45mm f/4 Pro produces very pleasing photographs – and the effective f/8 aperture makes working with small and close subjects much more convenient. Combined with the Focus Stacking or Focus Bracketing on Olympus bodies, this gives you a marvelous light macro imaging setup.
In terms of video, 12-45mm f/4 Pro performs much like the 12-40mm f/2.8 Pro; its autofocus is fast and quiet, with the constant aperture enabling you to push in and out without worrying about changes to exposure. The fact that it’s so lightweight, combined with greater ISO leeway when shooting video, makes it a versatile run-and-gun lens – particularly with the E-M1 Mark III and E-M5 Mark III, both of which features superior low light sensitivity and aggressive phase detect.


In The Photorealistic Effect… we saw how textures from photos could be overlaid onto 3D digital models as well as how digital models could be animated by human puppeteers: using motion capture to track the movement of articulation points on the human actor, this information could then be used to actuate similarly located points on the digital character mesh; and in 3D Models from Photos, we saw how textured 3D models could be “extruded” from single photograph by associating points on them with a mesh and then deforming the mesh in 3D space. In this post, we’ll explore further how the digital models themselves can be captured by scanning actual physical objects as well as by constructing models from photographic imagery.
We have already seen how markerless motion capture can be used to capture the motion of actors and objects in the real world in real time, and how video compositing techniques can be used to change the pictorial content of a digitally captured visual scene. But we can also use reality capture technologies to scan physical world objects, or otherwise generate three dimensional digital models of them.
Generating 3D Models from Photos
One way of generating a three dimensional model is to take a basis three dimensional mesh model and map it onto appropriate points in a photograph.
The following example shows an application called Faceworx in which textures from a front facing portrait and a side facing portrait are mapped onto a morphable mesh. The Smoothie-3d application described in 3D Models from Photos uses a related approach.
3D Models from Multiple Photos
Another way in which photographic imagery can be used to generate 3D models is to use techniques from photogrammetry, defined by Wikipedia as “the science of making measurements from photographs, especially for recovering the exact positions of surface points”. By using taking several photographs of the same object and identifying the same features in each of them, and then align the photographs, using the differential distances between features to model the three-dimensional character of the original objects.
DO: read the description of how the PhotoModeler application works: PhotoModeler – how it works. Similar mathematical techniques (triangulation and trilateration) can also be used to calculate distances in a wide variety of other contexts, such as finding the location of a mobile phone based on the signal strengths of three or more cell towers with known locations.
In the case of Intel RealSense devices, three separate camera components work together to capture the imagery (a traditional optical camera) and the distance to objects in the field of view (an infra-red camera and a small infra-red laser projector).
With their ability to capture distance-to-object measures as well as imagery, depth perceiving cameras represent an enabling technology that opens up a range of possibilities for application developers. For example, itseez3d is a tablet based application that works with the Structure Sensor to provide a simple 3D scanner application that can capture a 3D scan of a physical object as both a digital model and a corresponding texture.
Depth Perceiving Cameras and Markerless mocap
Depth perceiving cameras can also be used to capture facial models, as the FaceShift markerless motion capture studio shows.
Activity: according to the FAQ for the FaceShift Studio application shown in the video below, what cameras can be used to provide inputs to the FaceShift application?
Exercise: try to find one or two recent examples of augmented or mixed reality applications that make use of depth sensitive cameras and share links to them in the comments below. To what extent do the examples require the availability of the depth information in order for them to work?
Interactive Dynamic Video
Another approach to use video captures to create interactive models is a new technique developed by researchers Abe Davis, Justin G. Chen, and Fredo Durand at MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) referred to as interactive dynamic video. In this technique, or few seconds (or minutes) of video are analysed to study the way a foreground object vibrates naturally, or when gently perturbed.
Rather than extracting a 3-dimensional model of the perturbed object, and then rendering that as a digital object, the object in the interactive is perturbed by constructing a “pyramid” mesh over the pixels on the video image itself (Davis, A., Chen, J.G. and Durand, F., 2015. Image-space modal bases for plausible manipulation of objects in video. ACM Transactions on Graphics (TOG), 34(6), p.239). That is, there is no “freestanding” 3D model of the object that can be perturbed. Instead, it exists as a dynamic, interactive model within the visual scene within which it is situated. (For a full list of related papers, see the Interactive Dynamic Video website.)
SAQ: to what extent, if any, is interactive dynamic video an example of an augmented reality technique? Explain your reasoning.
Adding this technique to our toolbox, along with the ability to generate simple videos from still photographs as described in Hyper-reality Offline – Creating Videos from Photos, we see how it is increasingly possibly to bring imagery alive simply through the manipulation of pixels, mapped as textures onto underlying structural meshes.


We are a KODAK Lens Vision Centre, offering you unbeatable quality and value for money.
Choosing your new frames is often the most exciting aspect of visiting the opticians. However, while the frames you choose are important, the lenses you put in them are even more so, they’re the part that will improve your vision after all.
At Kings Opticians we have been chosen by KODAK Lens to be one of their lens experts.
This world renowned brand offers some of the best optical lenses available with unbeatable quality. We have expert knowledge of their products and are able to bespoke KODAK Unique lenses to provide the best vision correction available. Some of their lens coatings even come with a two year anti-scratch guarantee, that’s how confident they are of their products, with a no-quibble exchange policy.
With help from our lens specialists you can find the lenses to best suit your needs and lifestyle. Each member of our team regularly attends staff training to keep up-to-date with lens technology and how they will work in real life for our patients.
We take the time to listen and only recommend lenses that will benefit you.
Then when you come to collect your glasses we make sure that you’re happy with your glasses and your vision, making any adjustments that may be required and be assured that we are always there for any queries and aftercare no matter what they are or when they happen.
Some of the lenses we offer include:
When our eyes are unable to focus between distance and near vision an all vision (varifocal) lens enables us to claim back some of the focussing power we have lost by adapting your vision with a lens prescription. These lenses work at multiple distances, providing a seamless visual experience.
Transition lenses will save you the hassle if you’re finding you don’t want to switch your glasses to sunglasses when you step outside. These specialist lenses darken according to the light/ UV they are exposed to, leaving you with clear specs indoors and sunglasses when enjoying the sunshine.
Polarised lenses are designed to combat glare. Whilst spending time outdoors you’ve no doubt experienced glare, such as off the surface of a lake whilst fishing or off a wet road in the morningwhich then causes discomfort in your vision. These lenses allow you to see more comfortably as well as prevent conditions such as visual stress and tired eyes
Blue control lenses are recommended for those who spend lots of time in front of a computer screen. These lenses are designed to reduce the amount of blue light that is emitted from screens from entering the eyes which may lead to eye strain and headaches.
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Cotteridge 0121 486 2404
Maypole 0121 474 4748


Module 15 : erbium doped fiber amplifiers (edfa) gain erbium doped fiber earth ions implanted in the core of the optical fiber erbium is the preferred rare. Azimuthal dependence of modal gain and its impact on gain equalization in multimode erbium-doped fiber amplifiers. Erbium-doped fiber amplifiers are fiber amplifiers based on erbium (see also figure 1 in the article on erbium-doped gain media) (→ gain equalization). Introduction to optical amplifiers 4/17 a raman amplifier is distributed over a long span of optical fiber the gain for an erbium-doped fiber amplifier. Gain flattening and noise figure analysis dual stage single mode polarization maintaining bowtie erbium doped fiber with equalization filter, a gain. An erbium doped fiber that enables dynamic adjustment of the pump laser power for performing gain equalization across one or more wavelengths in response.
A new design for a gain flattened erbium doped fiber amplifier s vikrama uniformity of gain involves two aspects, namely gain equalization and gain flattening. The erbium doped amplifier is a high gain amplifier noise the principal source of noise in dfas is amplified spontaneous the erbium-doped fiber amplifier. Gain flattening of erbium doped fibre amplifier using leaky optical fibre design as an optical filter to achieve gain equalization in erbium-doped fibre. 19 october 2001 flexural waves on fiber and fiber bragg gratings for wdm switching and gain equalization of erbium-doped fiber amplifiers. Uniformity of gain involves two aspects, gain equalization and gain flattening uncluttered gain roll out in erbium doped fiber amplifier. Of few-mode erbium doped fiber ampliﬁer for modal and spectral gain equalization guillaume le cocq, yves quiquempois, and laurent bigot.
Design of a robust thin-film interference filter for erbium-doped fiber amplifier gain equalization pierre g verly. Edfa (erbium doped fiber amplifier) (see also figure 1 in the article on erbium-doped gain media) (→ gain equalization).
Gain equalization for erbium-doped fiber amplifiers by the synthesis of a long-period fiber grating. Edfa stands for erbium-doped fiber amplifier the bayspec’s edfa series products are mainly for metro applications is the non-flatness of the gain of an edfa. Request (pdf) | gain equalization me | we show experimental performance comparison of different equalization methods in erbium-doped optical amplifiers based on.
Positions, is proposed for flattening the gain spectrum of an erbium-doped fibre amplifier a ‘multiwavelength fiber-amplifier cascades with equalization. Latest results and future perspectives on few-mode work on few-mode erbium-doped fiber amplifiers and so as to favor gain equalization of a. Gain flattened erbium-doped fiber amplifier using simple equalizing film gain control in erbium-doped fiber amplifiers by lasing at 1480nm with photo induced. Journal of lightwave technology, vol 32, no 11, june 1, 2014 2133 adaptive modal gain equalization techniques in multi-mode erbium-doped fiber ampliﬁers.
Method and apparatus for a dynamic gain equalizer for an erbium doped fiber amplifier. We show experimental performance comparison of different equalization methods in erbium-doped optical amplifiers based on silica and zblan host materials. A simple scheme using a piece of sio2with an equalizing film platted on one side to get flattened gain gain flattened erbium-doped fiber equalization scheme.
Gain spectrum equalization of all-optical gain-clamped erbium-doped fiber amplifier. Student laboratory experiments on erbium doped laser educator kit which enables students to experimentally investigate the gain and erbium doped fiber.


Anteral offers polarizers that operate at MmW and THz frequencies with low transmission loss and high parallel isolation. Two different models are in stock, both of them are mounted in rotating frames with angular scale and clear apertures of 50 mm and 25 mm.
Anteral Wire Grid Polarizers consist of a simple pattern Cr-Cu-Au micro grid strip-array. This micro grid array is patterned following a photolithograpy process on a very thin (100 µm), ultra-low loss and flexible substrate for THz frequencies with low dielectric constant. The electric field is transmitted when polarized perpendicularly and reflected when polarized parallel to the grid array.
These polarizers can be used in MmW and THz systems in order to enhance the polarization sensitivity, beam splitting and generation of circular polarization.
|Model||Gap Width [µm]||Strip Width [µm]||Clear Aperture [mm]||Layers||Transmission Loss* [dB]||Parallel Isolation (Typical)* [dB]||Frequency Band [THz]|
|WGP-25-40||5||10||23.9||1||< 1.0||> 40||0 – 2|
|FWGP-50-40||5||10||48.3||1||< 1.0||> 40||0 – 2|
* Measured at WR2.2 frequency band. Further information available in the datasheets.
Don't hesitate to contact us regarding polarizers of different sizes or with special requirements.


Atomic Force/Scanning Probe Microscope (AFM/SPM)
The facility is equipped with a Bruker Catalyst Atomic Force/Scanning Probe Microscope for the high-resolution study of molecules in situ. The system works in both the contact and tapping modes. The AFM/SPM resides on a Zeiss AxioObserver Z1 inverted microscope stand equipped with fluorescence optics (DAPI, GFP, rhodamine), an Exfo X-cite fluorescence illumination system and an AxioCam MRm CCD camera for the concurrent imaging of fluorescent signals. A heater/perfusion chamber is available to permit live-cell imaging. The entire system is housed within a TMC Acoustic Vibration Isolation System.


Researchers have developed new polymer supplies that are perfect for making the optical hyperlinks essential to attach chip-based photonic elements with board-level circuits or optical fibers. The polymers can be utilized to simply create interconnects between photonic chips and optical printed circuit boards, the light-based equal of digital printed circuit boards.
“These new supplies and the processes they permit might result in highly effective new photonic modules primarily based on,” mentioned analysis workforce chief Robert Norwood from the College of Arizona. “They is also helpful for or making holographic shows for augmented and digital actuality purposes.
Silicon photonics expertise permits light-based elements to be built-in onto a tiny chip. Though most of the fundamental constructing blocks of silicon photonic gadgets have been demonstrated, higher strategies are wanted to manufacture the optical connections that hyperlink these elements collectively to make extra advanced methods.
Within the journal Optical Supplies Specific, the researchers report newsupplies that function a that may be adjusted with ultraviolet (UV) gentle and low optical losses. These supplies permit a single-mode optical interconnect to be printed straight right into a dry movie materials utilizing a low price, excessive throughput lithography system that’s appropriate with the CMOS manufacturing methods used to make chip-based .
“This expertise makes it extra sensible to manufacture optical interconnects, which can be utilized to make the Web—particularly the info facilities that make it run—extra environment friendly,” mentioned Norwood. “In comparison with their digital counterparts, optical interconnects can improve information throughput whereas additionally producing much less warmth. This reduces energy consumption and cooling necessities.”
Changing wires with gentle
The analysis expands on a vinylthiophenol polymer materials system often called S-BOC that the investigators developed beforehand. This materials has a refractive index that may be modified utilizing UV illumination. Within the new work, the researchers partially fluorinated S-BOC to enhance its gentle effectivity. The brand new materials system, known as FS-BOC, reveals decrease optical propagation losses than many different optical interconnect supplies.
“With this materials we will use a course of that we name SmartPrint to straight write optical interconnections between completely different optical printed circuit board parts, reminiscent of ion-exchange (IOX) glass waveguides supplied by our collaborator Lars Brusberg from Corning Integrated,” mentioned Norwood.
To carry out the SmartPrint course of, a FS-BOC movie is utilized on to a photonic part. No mechanical alignment is required as a result of the optical interconnect is made utilizing a maskless lithography system that calculates the place the interconnect is required by wanting on the elements after which writing the optical interconnect into the polymer utilizing photoexposure. No further processing is critical aside from briefly heating the polymer movie to 90 °C. As a result of the fabrication strategy is maskless, writing patterns could be modified with out making a brand new photomask.
Making a connection
To exhibit the, the researchers deposited them straight onto ion-exchange glass waveguide arrays, that are generally used for built-in photonic gadgets. They then printed the coupling options wanted to permit gentle to journey out of 1 IOX waveguide, propagate into the newly fabricated polymer interconnect, after which enter a second IOX waveguide adjoining to the preliminary IOX waveguide.
In accordance with the researchers, the polymer optical interconnects labored properly and confirmed low propagation and coupling losses, which suggests little or no gentle was misplaced because it traveled throughout the interconnect or between it and the opposite elements.
The researchers at the moment are working to enhance the fabric’s refractive index distinction and efficiency at excessive temperatures. “The next refractive index distinction would make the fabric extra tolerant to manufacturing variations whereas excessive temperature efficiency is probably going wanted for the interconnect to face up to solder reflow processes, which happen above 200 °C,” mentioned Norwood.
Julie I. Frish et al, Speedy photolithographic fabrication of excessive density optical interconnects utilizing refractive index distinction polymers, Optical Supplies Specific (2022).
New polymer supplies make fabricating optical interconnects simpler (2022, April 13)
retrieved 13 April 2022
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half could also be reproduced with out the written permission. The content material is supplied for info functions solely.


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Experience the exam of the future. Step into 21st century eye care with some of the most technological advanced eye care offices in San Diego. Offering cutting edge technology, highly trained doctors and an expanded experience providing you with your best vision possible.
Total Vision Care regularly invests in state-of-the-art instruments, learn more about some of our technology below and the benefits it brings to our patients.
i.Profiler ® plus– Objective Refraction and Corneal Topography
The i.Profiler® plus is the 4-in-1 system with ocular wavefront aberrometer, autorefractometer, ATLAS corneal topographer and keratometer. The fully automated measurement creates an optical 'fingerprint' of your eye and enables all measurements of both eyes including detection of aberrations in approximately 60 seconds.
ZEISS i.Scription – Wavefront Abberometry
Every eye is as unique as a human fingerprint. With i.Profilerplus® by ZEISS more than 2,500 reference points within your eye are examined to produce an extremely detailed vision profile. Unlike traditional exams, varying light conditions are also taken into account to provide customized visionâboth day and night. This comprehensive information is used to create a refined prescription or i.Scription®, that perfectly matches your unique vision profile. The resulting eyeglass lenses are produced to an accuracy far higher than seen in traditional eyeglass lenses and are personalized especially for your unique vision needs.
As a result, vision problems, such as blurry vision, halo effects, and visual discomfort can be recognized and improved. Eyeglass lenses with i.Scription technology can improve color and contrast, as well as vision at night and in low-lightâgiving you your best vision possible.
ZEISS precision lenses with i.Scription technology for better vision
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ZEISS i.Terminal – Centration Measurement System
Proper lens placement within your chosen frames is as important as an accurate prescription. Proper lens positioning minimizes headaches, incorrect body posture, and eye strain. Many details need to be taken into account, such as the distance between the eyes and pupils, the proportions of the face, the tilt and wrap of the frames, and even posture, to accurately position the lenses within the frames. Without these measurements, up to 40% of valuable visual acuity can be lost. This is important for single vision lenses and especially important for progressive lenses.
With the i.Terminal 2 by ZEISS, all of the necessary measurements are captures in only 60 secondsâto a precision of 1/10th of a millimeter–to create lenses made for your unique features.
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Humphrey® Matrix – Visual Field Analyzer
The Humphrey Matrix represents the latest breakthrough for early visual field loss detection testing. It combines the capability to detect glaucoma early and accurately with tools for long-term management and detect other eye diseases. It also enhances the ability to conduct a thorough visual field evaluation and assess treatment alternatives.
CIRRUS Photo 600 Instrument - Fundus Imaging and Optical Coherence Tomography(OCT)
CIRRUS photo delivers combined fundus and OCT reports that enable quick assessments for a wide variety of retina and posterior segment disorders. Retinal imaging and image analysis is important as many eye diseases as well as systemic diseases manifest themselves in the retina. These might include age-related macular degeneration, diabetic retinopathy and glaucoma.
Visuplan (NCT) – Non-contact Tonometer
A tonometry test measures the pressure inside your eye, which is called intraocular pressure (IOP). The measurement of IOP is part of a professional glaucoma evaluation and with the Zeiss Visuplan it is fast and very comfortable for our patients to do this test. Glaucoma is an eye disease that can cause blindness by damaging the nerve in the back of the eye.
Slit Lamp – Biomicroscope
From daily routine to specialized examinations it allows the doctor to see areas of the front of the eye, including eyelids, conjunctiva, iris, lens, sclera, cornea, retina and optic nerve. It helps in diagnosing items such as macular degeneration, detached retina, cataracts and injury to the cornea. Fun Fact- Carl Zeiss developed the first slit lamp back in 1911 together with Swedish ophthalmologist and Nobel laureate Allvar Gullstrand.
Visulens 500 – Automated Lensmeter
This verifies the correct prescription in a pair of eyeglasses to properly orient and mark uncut lenses, and to confirm the correct mounting of lenses in spectacle frames. It also can measure nearsighted and stigmatism in your eyewear and helps to determine if there has been changes in sight.
Visuphor 500 & Visuscreen 100 – Automated Subjective Refraction
Optimal visual outcomes in patients requires careful measurement of subjective and objective refractive error. The ZEISS VISUSCREEN 500 with Polatest technology comes with a variety of vision tests to perform monocular and binocular testing with different test charts, as well as special tests for children. It allows for easier visual acuity tests and allows the doctor to learn more about the interaction between both eyes.


The accuracy attained with huge style laser cutting is an outcome of the focused and concentrated beam that the laser produces. This high-energy beam of light is managed by computer laser cutting system system mathematical control (CNC) systems, making sure thorough precision in every cut. The degree of information that can be attained is unequaled, making it an excellent option for sectors where accuracy is non-negotiable.
In the world of commercial production, huge layout laser cutting has actually considerably affected manufacturing performance. The non-contact nature of laser reducing gets rid of the demand for device adjustments, minimizing downtime and enhancing general throughput. This performance is even more boosted by the capacity of lasers to reduce several items at the same time, maximizing the manufacturing procedure and lessening product waste.
Among the key benefits of huge style laser cutting is its capacity to collaborate with a varied variety of products. Whether it’s steels like stainless-steel and light weight aluminum, or non-metals such as acrylic, timber, or plastics, the laser’s convenience permits a wide range of applications. This flexibility has actually made it a favored option for complex layouts, great outlining, and intricate geometries.
While huge style laser reducing excels in accuracy and effectiveness, it is not without its obstacles. In addition, the selection of help gases, such as nitrogen or oxygen, can affect the high quality of the cut and need to be customized to the particular product being refined.
A vital factor to consider in opening the complete capacity of big layout laser cutting is recognizing the array of laser resources readily available. Carbon dioxide lasers, which run at a longer wavelength, are appropriate for reducing non-metallic products.
At its core, big style laser reducing includes making use of high-powered lasers to specifically reduce or etch products. Unlike typical techniques, such as mechanical cutting or sawing, laser reducing deals unrivaled accuracy and flexibility. This innovation has actually discovered its specific niche in a variety of markets, from aerospace and auto to signs and building layout.
Upkeep is one more important facet of making certain the long life and efficiency of big style laser reducing systems. Routine cleansing and calibration of optics, mirrors, and lenses are vital for protecting the precision of the laser beam of light. Carrying out an aggressive upkeep routine can avoid downtime and guarantee regular, high-grade cuts over the long-term.
One more element to be conscious of is the focal size of the laser lens. The focal size identifies the dimension of the laser beam of light and, as a result, the degree of information in the cut. Various focal sizes appropriate for various applications, with much shorter focal sizes supplying finer information and longer focal sizes permitting much deeper cuts.
Along with product factors to consider, the selection of laser power plays an essential function in big style laser cutting. Greater electrical power lasers can puncturing thicker products at faster rates, while reduced electrical power lasers use raised accuracy for thinner products. Striking the best equilibrium in between power and rate is important for attaining the wanted result in any kind of laser reducing application.
At its core, huge layout laser reducing entails the usage of high-powered lasers to specifically reduce or inscribe products. The accuracy accomplished via huge layout laser cutting is an outcome of the focused and concentrated beam of light of light that the laser produces. An essential factor to consider in opening the complete capacity of huge layout laser cutting is comprehending the variety of laser resources offered. In enhancement to product factors to consider, the selection of laser power plays an essential duty in huge layout laser cutting. Greater power level lasers are qualified of reducing via thicker products at faster rates, while reduced electrical power lasers provide enhanced accuracy for thinner products.
Huge style laser reducing stands at the center of accuracy production, providing unparalleled precision and flexibility. As innovation proceeds to advance, big style laser cutting is positioned to play an also much more considerable function in forming the future of production and layout.
Huge layout laser cutting has actually become an advanced modern technology in the world of accuracy production. As sectors pursue higher precision and performance, the fostering of this innovative method has actually come to be progressively common. In this extensive overview, we will certainly explore the complexities of big style laser cutting, discovering its applications, benefits, and the crucial factors to consider for opening its complete possibility.


I.D - Color reproduction¶
When it is a question of reproducing (synthesizing) colors, two systems are possible, according to the fact that the device is “passive” or reflecting (in painting, printing, etc.), i.e. that it needs to be illuminated, or “active”, and emits its own light (screen, projector, etc)
D.1 - Additive synthesis¶
In such an additive system, the most luminous color is the white: it results from the addition of the various primitives * of which the pixels of the device are made, in general a combination of green, red and blue.
This system works by adding rays of light to mix the colors.
A consequence to such a system is that a monochromatic color (the color of a primary* of the system, or the simulation of another monochromatic light obtained by mixing these primaries*) is inevitably less intense than a white one, contrary to the real world where everything is possible.
An additive system, being a light generator, can work in complete darkness, in which case the color reproduction can be perfectly controlled by not being influenced by any external light (as in a movie theater).
D.2 - Subtractive synthesis¶
When a color reproduction system is a reflective surface, it is the pigments that alter the light received; each pigment absorbs part of the rays received and reflects the rest. The resulting light is therefore necessarily of a lower intensity than that illuminating the surface: the system subtracts light rays from an available bouquet.
An important consequence is that a subtractive system depends on the light that illuminates it to reproduce colors: seen under a light poor in monochromatic rays*, an exposed painting will not render all its colors possible. For that, it is necessary to illuminate it not only with a white light, but with a white light “containing” enough different monochromatic* rays, of high quality1.
A painting, a poster or any other object illuminated under a monochromatic light will be able to reproduce only this monochromatic* color, at different intensities, whatever the pigments which compose them.
All light sources are not equal! With identical color, the light of different types of bulbs or fluorescent tubes will not be the same once reflected and “decomposed”: the sources of better quality will restore better the colors of the surfaces which they meet, and will be often “more pleasant”. ↩


The DCS-7410 and DCS-7510 are day and night outdoor cameras with built-in infrared LEDs. The cameras can detect moving objects in total darkness, for distances of up to 30 or 50 meters.
Equipped with a high-resolution Sony CCD image sensor, these cameras provide you with excellent image quality and level of detail. A built-in Infrared Cut Removable (ICR) flter in the DCS-7510 allows the camera to capture images in both good light and low light conditions by switching the infrared cut flter. Embedded with a powerful SoC (System-on-Chip), the cameras provide high-quality, real-time video compression in MPEG-4 and motion JPEG formats. These elements make the DCS-7410/7510 an ideal solution for 24-hour surveillance.


1MSc Student, Faculty of Electrical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran, nbm.
2Associate Professor, Nano-photonics and Optoelectronics Research Laboratory (NORLab), Shahid Rajaee Teacher Training University, Tehran, Iran,.
3Professor, Graz University of Technology, Institute of Microwave and Photonic Engineering, Graz, Austria,
In this paper, analysis the performance of PI, PI-like fuzzy, and parallel fuzzy P+ fuzzy I controllers for He-Ne lasers frequency stabilization by combination of frequency locking and power balanced methods is presented. He-Ne lasers can be attributed to an unstable system due to the influence of environmental factors on its' frequency. Therefore, the stabilization of He-Ne laser is so important in sensitive applications such as laser interferometers and nanometrology systems. The simulation results of controllers by powerful software MATLAB/SIMULINK-GUI show that parallel fuzzy P+ fuzzy I controller has better stabilization performance and integrated absolute error (IAE) than others. Also, frequency fluctuations of He-Ne laser is about 2×10-11 by parallel fuzzy P+ fuzzy I controller.


As of February 2015, S2 Corporation has received a second contract from the Intelligence Advanced Research Projects Activity (IARPA).
S2 Corporation was recently awarded a contract from the Intelligence Advanced Research Projects Activity (IARPA). The contract work plan is entitled “Efficient High-bandwidth Photonic Computational Engine for Selection and Filtering”, and has a total contract ceiling of $996,495. The contract was awarded in response to IARPA-BAA-12-03 Safe and Secure Operations; IARPA-BAA-12-03-PR-4521. For the next year, S2 will advance and demonstrate the capabilities of an extremely powerful and efficient high bandwidth optical information processor, based on spatial-spectral (S2) holographic signal processing technology. The S2 processor has the potential to continuously monitor, characterize, select, and filter many (>100) parallel broadband optical information channels, each with up to 100 GHz of spectral coverage. The tasks chosen aim to highlight the S2 processor’s capabilities in the processing of optical information. The effort will analyze and demonstrate the feasibility of the S2 processor in scalable laboratory demonstration to enable processing of optical signals, such as those in the trunk of optical networks. The innovation builds on past existing R&D efforts at S2 Corporation in collaboration with our university academic partner Montana State University (MSU). A subcontract is being awarded to MSU Spectrum Lab and industry partner, EOSpace.


10G CWDM SFP+ include CWDM SFP+ LR, CWDM SFP+ ER、CWDM SFP+ ZR, they are designed for 10G Ethernet and 2G/4G/8G/10G Fiber Channel applications. The CWDM SFP+ transceivers consist of two sections: transmitter section incorporates a colded EML laser while the receiver section consists of a APD photodiode integrated with a TIA. All CWDM SFP+ satisfy class I laser safety requirements and they are made with default Digital diagnostics functions. CWDM SFP+ wavelength is 1270nm to 1610nm, working distance from 10km to 20km, 40km and 80km. All these CWDM SFP+ are made to work with single mode optical fibers.
CWDM 10G SFP 10km
CWDM 10G SFP 10km is a very compact 10Gb/s optical transceiver module for serial optical communication applications at 10Gb/s.
CWDM 10G SFP 20km
The CWDM 10G SFP 20km converts a 10Gb/s serial electrical data stream to 10Gb/s optical output signal and a 10Gb/s optical input signal to 10Gb/s serial electrical data streams.
CWDM 10G SFP 40km
The high performance 1270～1610nm CWDM EML transmitter and high sensitivity PIN receiver provide superior performance for Ethernet applications at up to 40km links.
CWDM 10G SFP 60km
CWDM 10G SFP 60km complies with SFF-8431, SFF-8432 and IEEE 802.3ae 10GBASE-ER. Digital diagnostics functions are available.
CWDM 10G SFP 80km
CWDM 10G SFP 80km is a very compact 10Gb/s optical transceiver module for serial optical communication applications at 10Gb/s.
10G CWDM SFP+ Transceivers Applications:
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The sensor in the Wiimote is a PixArt optical sensor that determines where the Wiimote is pointing. Unlike a light gun that senses light from a television screen, the Wii Remote senses light from the console's Sensor Bar (RVL-014), which allows consistent usage not influenced by the screen used. The Sensor Bar is about 20 cm (7.9 in) long and has ten infrared LEDs, five at each end of the bar. The LEDs furthest from the center are pointed slightly outwards, the LEDs closest to the center are pointed slightly inwards, while the rest are pointed straight forward. The Sensor Bar's cable is 353 cm (11 ft 7 in) in length. The bar may be placed above or below the television, centered horizontally, in line with the front of the television or the front of the surface the television is placed on. The Remote should be pointed approximately towards the Sensor Bar; precise pointing is not necessary so long as it is within the limited viewing angle of the Wii Remote.
Due to the sensor being IR-based, it can detect any IR signal as input, this include candles.


These 2 models of glasses are ideal for fishing.
Aqua sight has a 'sports' frame and is very lightweight.
Polar eyes have a full frame design.
The amber polarising lenses are designed to block out harmful UVA and UVB rays and have a CE Category 3 rating. This is a dark tint that is ideal for strong sunlight and reducing surface glare.
Each pair of Sunglasses also comes with a very handy, detachable sports strap made from elasticated Neoprene.
These stylish and practical sunglasses also come supplied in a modern zip-up EVA case complete with anti-static cleaning cloth.


This work focuses on the design and development of quadrotors that are capable of autonomous landing on a stationary platform. This problem is motivated by the fact that quadrotors have to land frequently to charge their batteries, as maximum flight time is rather short with the current state-of-art. In this work, we particularly consider three different quadrotor systems including the quadrotor constructed in our Intelligent Systems Laboratory, the ISL quadrotor. The ISL quadrotor is endowed with a camera attached to a gimbal stabilizing the view for visual sensing, a laser range sensor for measuring the altitude, PIXHAWK flight controller and a Raspberry Pi 3 (RPi3) as an onboard computer for autonomous operation. The software is designed and developed in Robot Operating System (ROS) and includes control, visual processing and serial communication with the flight controller. The code is designed to be multi-threaded as have the quadrotor be capable of doing visual processing concurrently with flight control. The dynamic modeling of the quadrotor is based on one of the commonly used models. For the landing task, position, altitude, and velocity controllers based on proportional and derivative (PD) control are developed. Position information is provided by visual feedback through detecting the marker on the landing platform. The developed approaches are first tested on the Gazebo simulation environment. We also conduct similar landing experiments on the ISL quadrotor for different wind, light, and initial altitude conditions and observe that the quadrotor is able to land autonomously within approximately 80 cm error range on a stationary platform that is marked by a 50cm $\times$ 50cm ArUco marker. The designed quadrotor is also capable of tracking a platform that is moving with a slow linear velocity.
For more info, pls contact Mustafa Mete.


Tamron SP A025 70-200mm F/2.8 VC Di USD Lens For Nikon F - Black (AFA025N-700). According to latest rumors Sigma will soon announce a new 70-200mm lens F2.8 lens. The lens is expected to announce before Photokina 2018. The upcoming version will replace the existing 70-200mm lens. These lenses will initially arrive for Canon, Nikon and Sigma Native mount. We will update you soon as we get any new information. Tamron SP A025 70-200mm F/2.8 VC Di USD Lens For Nikon F - Black (AFA025N-700).
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While the Tamron 70-200mm f/2.8 Di VC USD Lens is not Tamron's first 70-200mm f/2.8 lens, it is their first version to include vibration control. VC alone is a great upgrade feature, but the upgraded image quality in this lens is also big bonus. This lens 70-200 VC overall great image quality and good performance at a moderate price. 56 minutes ago · NO PAYPAL In immaculate condition comes with len hood and tripod collar and uv filter Pick up North Tivoli or postage is available NO PAYPAL, 1252635173. Tamron Lens SP 70-200mm F/2.8 Di VC USD (Nikon mount) review: High performance and excellent value Introduction Appealing to sports and action photographers as well those who use the immensely versatile range for portraits, the Tamron SP 70-200mm f/2.8 is a rightly popular lens.
Feb 06, 2017 · Manufacturer description: The Tamron SP 70-200 F2.8 Di VC USH G2 substantially enhances the features of its predecessor. These include a thorough review of the optical, mechanical and electronic designs to increase autofocus speed and precision, reinforce VC (Vibration Compensation) functions and to shorten the minimum operating distance. Tamron 70-200 F2.8 G2 2. Nikon 70-200 F2.8 VRii กำลังชั่งใจอยู่ว่าตัวไหนดีกว่ากันครับ เพราะว่า Nikon 70-200 F2.8 VRii เป็นเลนส์ที่ออกมานานแล้ว ราคามือ 2. The Tamron SP 70-200 F/2.8 Di a high-resolution ultra-compact fast tele zoom. Its F/2.8 aperture, SP performance and agile telephoto make it ideal for fast action sports to spot news to posh weddings. Tamron’s SP 70-200mm F/2.8 Di LD (IF) Macro exemplifies the second of the two zoom focal lengths considered essential by many professionals..
Pentax-D HD FA* 70-200 F2.8 ED DC AW Tamron SP 70-200mm F/2.8 Di VC USD With full-time manual focus, you can move the focus ring whilst it is in AF (autofocus) mode. While the Tamron 70-200mm f/2.8 Di VC USD Lens is not Tamron's first 70-200mm f/2.8 lens, it is their first version to include vibration control. VC alone is a great upgrade feature, but the upgraded image quality in this lens is also big bonus. This lens 70-200 VC overall great image quality and good performance at a moderate price. May 18, 2016 · → Sigma has a new patent for a 70-200mm f/2.8 DG OS HSM | Sport lens that will most likely replace the current 70-200mm f/2.8 EX DG OS HSM. Next are several new new lens patents from Canon and more: → Canon 50-300mm f/4.5-5.6 IS DO lens patent for APS-C mirrorless camera. → Canon EF-M 15-50mm f/3.5-5.6 IS .
Improvements to the new SP 70-200mm F/2.8 G2 extend well into the lens barrel. Tamron has reduced the MOD from 1.3m (50.7 in) in our older model to 0.95m (37.4. The Tamron 70-200mm SP f/2.8 Di VC USD G2 is a fast, quiet lens with a constant f/2.8 maximum aperture, ideal for wedding & event photographers. Buy online!. Mar 13, 2007 · The Tamron 70-200 ƒ/2.8 telephoto zoom was announced in February 2008, updating and replacing their existing 70-200mm ƒ/2.8 zoom lens. The economical lens.
The Canon 70-200 f2.8 and the Sigma 70-200 f2.8. Because of the large price difference between these two lenses people often wonder what really sets them apart. More specifically why you may or may not want to purchase the Canon Len over the Sigma or vise verse. NO PAYPAL Immaculate condition Come len hood and tripod collar and uv filter Pick up North Tivoli or postage is available at buyer expense NO PAYPAL, 1252496223. Amazon, Camera lens comparison, Camera Lenses, Canon EF 70-200mm f/2.8L IS II USM Telephoto Zoom Lens for Canon SLR Cameras, Nikon, Portrait photography, Sigma 70-200mm f/2.8 APO EX DG HSM OS FLD Large Aperture Telephoto Zoom Lens for Canon, Sony or Sigma, Tamron SP 70-200MM F/2.8 DI VC USD Telephoto Zoom Lens for Canon EF or Nikon Cameras, Tony Northrup.
Shop with confidence at Abe's of Maine Serving our customers for over 30 Years! PRODUCTS ARE: Factory fresh; In a secure cart; Includes all manufacturer supplied accessories. The Tamron SP 70-200mm f/2.8 Di VC USD G2 lens is on the same level playing field as lenses costing up to twice as much, punching far above its weight. It may not have the same silky smoothness in operation as its more expensive competition, but it delivers the goods, making no compromise on image quality. Tamron 70-200 f 2.8 DI VC USD Gen.1 für Canon. Ich biete mein Tamron 70-200 Blende 2.8 für Canon an, da ich das System wechseln werde. Das....
Sigma is, in many ways, the latecomer to the party here. Tamron has released two generations of their 70-200mm F2.8 VC lenses since Sigma’s EX lens was released in 2010. Both Canon and Nikon have released newer versions of their own 70-200mm F2.8 lenses in that period as well. The Tamron SP 70-200mm f/2.8 Di VC USD was introduced in 2012. It's a lens designed for the higher expectations of digital photographers. It offers "VC" (Vibration Compensation), Tamron's version of Image Stabilization. But it is also a 'third party' lens that carries the potential for compatibility issues with future Canon bodies. It's a very good lens, but not quite up to the standard of the Canon EF 70-200mm f/2.8 L IS II which was arguably the best mass-produced zoom lens in the world .... Oct 23, 2019 · Looking for an affordable alternative to Canon and Nikon's 70-200mm F/2.8 zooms? Tamron's upgraded SP 70-200mm F/2.8 G2 is an excellent option..
The SP 70-200mm f/2.8 G2 follows suit with an almost uniform chassis save for the focus/zoom rings and the switches that control vibration control and auto-focus; Tamron went as far as recessing the tripod collar to keep within the ascetic (as it did for the 150-600mm f/5-6.3 DI VC USD G2).. The SP 70-200mm f/2.8 G2 follows suit with an almost uniform chassis save for the focus/zoom rings and the switches that control vibration control and auto-focus; Tamron went as far as recessing the tripod collar to keep within the ascetic (as it did for the 150-600mm f/5-6.3 DI VC USD G2). The main contender is the Sony FE70-200 F2.8 GM. The Tamron is much lighter, smaller to carry in a bag , can focus closer and is half the price of the Sony FE70-200 F2.8 GM; The Sony FE70-200 F2.8 GM keeps its contant length when focusing, optical stabilisation and additional buttons (focus hold, distance limitation, AF/MF, OSS) and is compatible with Sony TC1.4 and TC2.0.
Buy Tamron SP 70-200mm f/2.8 Di VC USD G2 Lens for Nikon F featuring F-Mount Lens/FX Format, Aperture Range: f/2.8 to f/22, One XLD Element, Five LD Elements, eBAND, BBAR, and Fluorine Coatings, Ultrasonic Silent Drive Autofocus Motor, VC Image Stabilization, Dust and Moisture-Resistant Construction, Removable Arca-Compatible Tripod Mount, Rounded Nine-Blade Diaphragm, Compatible. A popular telephoto zoom for a variety of shooting applications, this Canon EF-mount SP 70-200mm f/2.8 Di VC USD G2 Lens from Tamron is characterized by its bright f/2.8 constant maximum aperture, as well as sophisticated optical and physical designs. Find great deals on eBay for tamron 70-200 2.8 and tamron 70-200 2.8 canon. Shop with confidence.


ARCHON DH30 II Canister Diving Light is a split diving light. It is lightweight and easy to carry. It is equipped with white LEDs for professional lighting. It has super long-range capability, which enables divers to display the lighting they want underwater. This lamp greatly enhances the professionalism of the lamp and is ideal for technical diving and recreational diving.
Split diving light with American LED wick
Smooth aluminum reflector, super high temperature treatment, laminated alloy reflective film
Unique luminous ring and side light design greatly enhance the application of light under water
Professional micro computer chip with low power prompt and low power protection
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Light Source: 3 * CREE XM-L2 (color temperature 6500K)
Maximum brightness: 3600 lumens
Light angle: 8 degree center angle spotlight + 110 degree side light
Working voltage: 9-14V
Lamp body size: the lamp head diameter is 60 mm, the lamp cap length is 91 mm, the battery box diameter is 31 mm, and the battery box length is 265 mm. Line length 1.2 meters
Lens specifications: 8 mm (imported PC material)
Battery model: 3 * 26650 (with lithium ion rechargeable battery with protection board)
Life time: 200 minutes for highlights, 450 minutes for low highlights, 500 minutes for highlights
Light body weight: 866 grams (without battery)
Water weight: 580 grams (with battery)
Land weight: 1157 grams (with battery)
Waterproof depth: 100 meters
3*archon 26650 Li-ion battery
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LED Light Bulbs
*UPDATE 10/2014: LED light bulbs are getting better and more affordable almost every day! For example, Cree just introduced their newest generation of energy-efficient led light bulbs for under $10 each. Click HERE to learn more!*
If you're interested in greening your home to save energy, resources, and money, one of the easiest and most affordable things to do is change how you light it. In today's green home, that usually means using compact fluorescent bulbs (CFLs) instead of traditional incandescent bulbs. However, new advances in LED light bulbs may mean that the CFL's days as efficiency-leader are almost over.
LEDs: The New Kid on the Block
LED (light-emitting diode) lights work by passing electrons through a semiconductor material. That's as scientific as we'll get when explaining where an LED's light comes from.
While LED light technology has been around for awhile, the use of LEDs in residential light bulbs is relatively new. Much like the early days of the CFL, LED bulbs had some issues that most consumers could not overcome.
Researchers originally had trouble creating LED light bulbs that could produce light capable of competing with, and replacing, the warm soft light of incandescent bulbs. Also, early LED lights were not anywhere bright enough to provide enough light to fill a room.
Add to that the fact that LED light bulbs were (and still are) quite expensive, and you can easily see why they haven't taken off….yet.
The Difference Between LED Lights and Other Lights
Incandescent bulbs and CFLs emit light in all directions. LED lights emit light directed in a specific direction. For example, a CFL or incandescent bulb in a recessed can will waste half of the light it produces. A recessed LED light will project its light only downward where it's needed.
LEDs and Energy Efficiency
If incandescent light bulbs weren't such inefficient energy-wasters, we probably wouldn't be discussing LEDs today. But they are, and that has driven a search for new, more efficient lighting technology, resulting in today's CFLs and tomorrow's LEDs.
LED bulbs are on average 75% more efficient than incandescent light at producing the same level of light. The U.S. Department of Energy estimates that a rapid switchover to LED lighting in the U.S. by 2027 would deliver energy savings of roughly $265 billion. That's enough energy to avoid building 40 new coal-powered power plants, and enough to reduce the nation's electricity demand for lighting by 33%!
More Advantages of LED LIghts Over CFLs
Today's new LED lights are about as efficient as CFLs, about 75% more efficient than incandescent's. But while CFLs last much longer than incandescent, up to 7,000+ hours, LED lights can last upwards of 25,000 hours. That's a dramatic improvement in durability.
LED lights are also dimmable, while most CFLs cannot be used with dimmers. This allows LED lights to be used in a much wider number of applications around the home.
Advancements in the quality of LED light is also going to make them preferable to CFLs. LEDs can be made to create any color in the spectrum; this is going to give interior decorators and homeowners amazing new lighting choices in the near future.
LEDs contain absolutely no mercury, unlike CFLs. This means not having to worry about breaking bulbs or disposal of dead bulbs. But LED bulbs last so long, you'll probably never have to throw one out!
Energy Star and LED LIghts
The rush to get new LED products to market means that quality may suffer. To counter this, Energy Star now certifies LED lights. In order to qualify for the Energy Star label, LEDs must demonstrate the following:
- Brightness is equal to or greater than existing lighting technologies(incandescent or fluorescent) and light is well distributed over the area lighted by the fixture.
- Light output remains constant over time, only decreasing towards the end of the rated lifetime (at least 25,000 hours or 22 years based on use of 3 hours per day).
- Excellent color quality. The shade of white light appears clear and consistent over time.
- Efficiency is as good as or better than fluorescent lighting.
- Light comes on instantly when turned on.
- No flicker when dimmed.
- No off-state power draw. The fixture does not use power when it is turned off, with the exception of external controls, whose power should not exceed 0.5 watts in the off state.
LED lights are in their infancy. Costs are still quite high, and brightness is still on the low end, especially compared with CFLs, but the industry is evolving rapidly. Several companies will be introducing exciting new LED products in the next few months that will revolutionize the light bulb world.
As LED technology continues to improve and catch on with the public, prices will fall over time, much like they have with CFLs.
At Green Home Source, we are very excited about both the energy-saving and decorating potential that LED lighting will create in the coming years.comments powered by Disqus


This laboratory is fully equipped to perform femtosecond laser micromachining inside transparent materials or on the surface of any material.
Two femtosecond laser sources are available in this laboratory for the microfabrication activity.
A reconfigurable setup of mirrors allows to steer either one of the two laser beams or their second harmonic, produced using an LBO crystal, to the machining area. Several microscope objectives with numerical apertures from 0.3 to 1.4 are available for focusing the laser beam on the sample.An air-bearing translation system (Aerotech FiberGLIDE 3D) enables three-axis motion of the sample with 50 nm accuracy and with speeds up to 300 mm/s. The stages are computer controlled and programmable to perform complex design microfabrication.


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The misuse of laser pointers (sometimes referred to as laser pens) reported in the press has generated public concern over the safety of these devices. The following provides basic information on the properties of laser radiation, the different laser Classes and summarises the HPA position on the issue of the safety of laser pointers. The advice from the HPA takes account of the current British Standard for laser safety, and the technically equivalent European and International Standards. NRPB (now the Radiation Protection Division of the HPA) was involved in the initial development of these Standards and currently provides input to the British Standards Institution and International Electrotechnical Commission Technical Committees responsible for maintaining these documents.
NRPB provided advice to the then Department of Trade and Industry concerning the safety of hand-held laser pointers and the optical hazards posed by the use of these products.
Lasers are devices which produce radiation with unique properties. It is these properties that distinguish laser radiation from the radiation produced by more familiar sources such as the sun or the common household electric light bulb. When the radiation emitted by a source can be detected by the eye and produces a sensation of vision, it is referred to as light. An electric light bulb produces radiation comprising many different wavelengths, perceived as white light, and emits fairly equally in all directions. The radiation produced is said to be highly divergent, i.e. the light spreads out rapidly as the observer moves away from the bulb. It is this property which allows the illumination of large areas using a single light bulb. In contrast a laser will produce radiation over a very narrow wavelength band, so narrow that the laser is referred to as a monochromatic or single wavelength source. If the laser emits in the visible region then the radiation is perceived as a single colour. The wavelength of light is usually measured in nanometres, or one-thousand-millionth of a metre and is abbreviated to "nm". The laser also produces a very narrow beam which diverges, or spreads out, very little with increasing distance from the source. This low divergence property means that the laser output is highly directional, forming a pencil-like beam that will still appear as a small spot when shone against a surface, even at large distances (i.e. 100 metres plus). A consequence of this is that high power devices can present a hazard over considerable distances. When considering the safety implications of the laser beam an important parameter is the amount of power in the beam divided by the cross-sectional area of the beam. This is called the irradiance and is usually quoted in watts per square metre or W m -2.
Laser pointers have been used as presentational aids by professional trainers for a number of years, with no reported incidents in the UK. They are usually portable, low powered, battery operated, hand held laser devices. Commonly available laser pointers generally emit red coloured light (wavelengths between 630 and 670 nm), although more expensive devices are available which emit green coloured light (532 nm). The response of the human eye is wavelength dependent and peaks at around 550 nm, the response decreasing as either end of the visible spectrum is approached (400 nm to 780 nm). As a result, if laser pointers are compared at three different wavelengths (670 nm, 635 nm and 532 nm) but at the same radiant power, the brightness as perceived by the eye will be approximately in the ratios 1 : 10 : 30. Laser pointers emitting light with the laser wavelength which is closer to the eye's peak response are therefore capable of producing the adequate visual stimulus at lower radiant powers.
Laser pointers can be pen shaped, and these are the type usually marketed for professional use (figure 1). Devices intended for the novelty market can be of different shapes. These novelty laser pointers may also contain either interchangeable effects heads (figure 2) or have an integral selector control (figure 3). They are commonly supplied as key rings.
Laser pointers sold in the UK should be classified in accordance with the current British Standard 1 on laser safety. This document specifies requirements for the manufacturers of laser products to ensure that the risk of accidental exposure is minimised through the use of engineering control features and product labelling, and by specifying minimum requirements for the supply of product information to allow for its safe use. A user's guide to the Standard also contains advice to the user of laser products in terms of procedural controls and Class-specific training requirements 2. In the USA there is a Federal Performance Standard for Laser Products 3 which has similar requirements, but there are differences between these two documents. This is discussed below (see Laser Classes).
If product mislabelling is suspected, or there is doubt over the classification of a product then measurements should be carried out in accordance with the requirements of the British Standard to determine the actual laser Class to which the device should be assigned. A visual inspection of a laser product or its laser output will not provide any indication of the appropriate Class for the device.
The British Standard sets out seven Classes of laser, these are Class 1, Class 1M, Class 2, Class 2M, Class 3R, Class 3B and Class 4. The higher the Class number, the greater the laser radiation hazard posed by the laser. Class 4 lasers are high power devices, usually needing a mains power supply. Class 4 lasers are used for specific applications in research, medicine and industry. They are also used in the entertainment industry. Class 4 lasers are not designed to be used as laser pointers.
The classification system uses the concept of an Accessible Emission Limit (AEL). An AEL is the maximum value of accessible laser radiation to which an individual could be exposed during the operation of a laser and is dependent on the laser Class. The AEL values are in turn based on Maximum Permissible Exposure (MPE) levels. An MPE is a level of laser exposure which it is believed an individual could be exposed to without incurring an injury. An MPE may therefore be considered as a maximum safe level of exposure. MPE levels are specified for both the eye and skin as a function of the wavelength of the laser radiation and the duration of exposure. These MPE values are internationally agreed.
A laser is assigned to a particular Class when the measured emission level exceeds the AEL for all lower laser Classes but does not exceed the AEL for the Class assigned. For example, a laser will be assigned as a Class 3R laser product when the maximum measured accessible emission level exceeds Class 1, Class 1M, Class 2 and Class 2M AEL values but does not exceed the Class 3R AEL. Once a laser has been assigned to a particular Class there are other requirements prescribed in the British Standard which should be met. These will include product labelling and customer information, and may include specific engineering control features to be incorporated in the laser product depending upon the Class assigned. A summary of the laser Classes is given below.
The following laser classification scheme is taken from BS EN 60825-1: 1994 incorporating Amendment Numbers 1, 2 and 3, September 2002 2.
Class 1 lasers are products where the radiant power of the laser beam accessible (the accessible emission) is always below or equal to the Maximum Permissible Exposure value. Therefore, for Class 1 lasers the output power is below the level at which it is believed eye damage will occur. Exposure to the beam of a Class 1 laser will not result in eye injury. Class 1 lasers may therefore be considered safe. However, Class 1 laser products may contain laser systems of a higher Class but there are adequate engineering control measures to ensure that access to the beam is not reasonably likely during normal use. Examples of such products include laser printers and compact disc players.
Class 1M lasers are products which produce either a highly divergent beam or a large diameter beam. Therefore, only a small part of the whole laser beam can enter the eye. However, these laser products can be harmful to the eye if the beam is viewed using magnifying optical instruments. Some of the lasers used for fibre-optic communication systems are Class 1M laser products.
Class 2 lasers are limited to a maximum output power of 1 milliwatt or one thousandth of a watt (abbreviated to mW) and the beam must have a wavelength between 400 and 700 nm. A person receiving an eye exposure from a Class 2 laser beam, either accidentally or as a result of someone else's deliberate action (misuse) will be protected from injury by their own natural aversion response. This is a natural involuntary response which causes the individual to blink and avert their head thereby terminating the eye exposure. Repeated, deliberate exposure to the laser beam may not be safe. Some laser pointers and barcode scanners are Class 2 laser products.
Class 2M lasers are products which produce either a highly divergent beam or a large diameter beam in the wavelength range 400 to 700 nm. Therefore, only a small part of the whole laser beam can enter the eye and this is limited to 1 mW, similar to a Class 2 laser product. However, these products can be harmful to the eye if the beam is viewed using magnifying optical instruments or for long periods of time. Some lasers used for civil engineering applications, such as level and orientation instruments are Class 2M laser products.
Class 3R lasers are higher powered devices than Class 1 and Class 2 and may have a maximum output power of 5 mW or 5 times the Accessible Emission Limit (AEL) for a Class 1 product. The laser beams from these products exceed the maximum permissible exposure for accidental viewing and can potentially cause eye injuries.
This Class, which was introduced into the British Standard with Amendment 3, replaces the former Class 3A and the low power part of Class 3B. Class 3A had the additional requirement that the irradiance of the laser beam should not exceed 25 W m -2. The effect of the irradiance limit was to restrict the power admitted to a fully dilated human eye (taken as a 7 mm acceptance aperture) to 1 mW. As such, accidental exposure to a Class 3A laser beam was no more hazardous than accidental exposure to a Class 2 laser beam. An individual accidentally exposed would be protected from injury by their natural aversion response. Class 3A laser pointers were, however, potentially hazardous when viewed with an optical aid such as binoculars and were therefore not suitable for the general consumer.
To satisfy the irradiance criteria, a laser pointer with an output power greater than 1 mW would have to produce an expanded beam to reduce the irradiance below 25 W m -2. As the characteristic feature of a laser pointer is the small spot produced by the narrow beam, expanding the beam area to satisfy the irradiance criteria effectively destroys this useful property. It was therefore extremely unlikely that a laser pointer with a power output in excess of 1 mW would satisfy the Class 3A AEL criterion. Therefore, in general, laser pointers were either Class 1, Class 2 or Class 3B products. The former Class 3B laser pointers, which did not exceed 5 mW, are now Class 3R.
The American Standard 3 does not have the Class 3A irradiance criteria previously specified in the British Standard. Therefore, a correctly classified American Class IIIA laser pointer would have become Class 3B device when classified against the British Standard. The use of Roman numerals should indicate that the product has been classified in accordance with the American Standard. In practice, examples occur where an inappropriate 3A label has been substituted for the IIIA label. All of the American IIIA laser products will now be Class 3R under the British Standard.
Examples of Class 3R products include some laser pointers and some alignment products used for home improvement work.
Class 3B lasers may have an output power of up to 500 mW (half a watt). Class 3B lasers may have sufficient power to cause an eye injury, both from the direct beam and from reflections. The higher the output power of the device the greater the risk of injury. Class 3B lasers are therefore considered hazardous to the eye. However, the extent and severity of any eye injury arising from an exposure to the laser beam of a Class 3B laser will depend upon several factors including the radiant power entering the eye and the duration of the exposure. Examples of Class 3B products include lasers used for physiotherapy treatments and many research lasers.
Class 4 lasers have an output power greater than 500 mW (half a watt). There is no upper restriction on output power. Class 4 lasers are capable of causing injury to both the eye and skin and will also present a fire hazard if sufficiently high output powers are used. Lasers used for many laser displays, laser surgery and cutting metals may be Class 4 products.
The British Standard provides advice on the use of lasers for demonstrations, displays and exhibition and states that only Class 1 or Class 2 devices should be used in unsupervised areas unless under the control of experienced well-trained operators. Laser pointers used by, for example, professional lecturers in the workplace are considered to fall under this category. Minimum training requirements are specified for operators using lasers of a higher Class for these purposes due to the risk of eye injury. Such training should include guidance to the user on the risks from the laser beam and advice not to point the beam at anyone.
The HPA Radiation Protection Divison has examined many laser pointers available to the general public in order to assess their laser Class and have found a significant proportion of these products to be Class 3R lasers and several Class 3B. The body's natural aversion responses are unlikely to provide adequate protection from eye injury for Class 3B laser pointers.
Green laser pointers have given a particular cause for concern. Many of these are not even suitable for professional use because they cause afterimages in people viewing the beam on a projection screen. Those close to the screen may also experience a grey 'comet tail' following the beam as it is moved across the screen. Some of these green laser pointers produce beams that consist of a series of bursts (or pulses) of light with high peak powers in each pulse. The manufacturers often quote average power, which gives a misleading indication of the risk. Because of the way the green beam is generated, there may also be other, invisible, laser beams emitted. Specialist equipment is needed to identify these problems.
Although the risk of a permanent eye injury from a laser pointer may be small, an individual receiving even a transient eye exposure from a laser pointer will experience a bright flash, a dazzling effect, which is likely to cause distraction and temporary loss of vision in the affected eye and possibly after-images. The time taken to recover from these effects will vary for different individuals and will also be dependent on the ambient light level at the time of exposure. Medical attention should only be sought if after-images persist for hours, or if a disturbance in reading vision is apparent.
Many of the laser pointers assessed by the HPA were either incorrectly labelled or not labelled at all. It was also unusual to find any information on laser safety or warnings on the implications of potential misuse supplied with the products.
A number of high-power laser pointers, generally emitting green beams, are available over the internet. The laser beam powers may be up to a few hundred milliwatts. These devices are extremely dangerous and are not suitable for sale to the public.
The HPA considers the professional use of a Class 1 or Class 2 laser pointer as a training aid in the workplace to be justified, and regards these Classes of laser product as being generally adequate for such use. The use of Class 3R laser pointers up to 5 mW may be justified for some applications in the workplace where the user has received adequate training.
The HPA advises that the sale of laser products to the general public for use as laser pointers should be restricted to Class 1 or Class 2 devices which should be classified in accordance with the requirements of the current British Standard and should be sold with sufficient accompanying information to enable the user to operate the product in a safe manner. Toys should be Class 1 or of such low output that they do not need to be classified.
After seeking advice from NRPB (now the Radiation Protection Division of the HPA) the then Department of Trade and Industry urged Trading Standards Authorities to use their existing powers under the General Product Safety Regulations 2005 4 to remove laser pointers of a Class higher than Class 2 (as defined in the British Standard) from the general market. Such devices are too powerful for general use as laser pointers and present an unacceptable risk in the hands of the consumer because they may cause eye injury in normal reasonably foreseeable use.
(revised October 2007)
Last reviewed: 21 May 2010