Canon applies to patent double-sided micro lenses designed for better edge performance
Canon engineers have developed a new design for the micro lenses it uses on imaging sensors that it claims will reduce vignetting and false coloration at the edges of the picture. The new designs have a bi-convex lens that uses the upper surface to collect light and the lower to channel the light more effectively to the photodiode. The patent application shows the lower face of the micro lenses with a convex surface featuring an off-center vertex. Canon says these would be placed at the edges of the sensor to direct light approaching from a steeper angle. The idea is to direct more of the light toward the photodiode than can be achieved with standard single-micro-lens designs.
As pixels have depth it can be difficult to channel light from the camera’s lens down the ‘well’ to reach the photodiode unless it approaches straight-on. When a pixel is positioned at the edge of the sensor array it becomes more difficult because light approaches from an extreme angle and can miss the photodiode, as the refractive index of the micro lens isn’t high enough to bend it directly down the well. Since certain colors experience different refractive indices, some wavelengths of light don't make it to the photodiode either. Thus, pixels outside the central area can report less light – and false colors – compared to those in the middle of the sensor.
Canon’s new dual micro lens design aims to take more control of the light as it enters and exits the micro lens, and to channel it in a more vertical direction down the well so that less is lost. This should in theory improve both vignetting and false coloration nearer to the edges of the image.
For more information see Canon's full patent application.
Extract from the patent:
The lower surface 102 of the microlens 103 has an asymmetrical shape with a position nearest to the photoelectric conversion device 104 (a position at which the thickness from a center plane 130 of the microlens 103 is the maximum) shifting from the center position of the microlens 103 to the central side of the pixel array 110A. The lower surface 102 of the microlens 103 has a convex shape with respect to the photoelectric conversion device 104.
Each microlens 103 is formed from a material having a higher refractive index than a material in contact with the lower surface 102 at a position between the microlens 103 and the photoelectric conversion device 104. The microlens 103 is formed from, for example, a color filter material.
The upper surface 101 of each microlens 103 has a convex shape with respect to the incident side of incident light. The incident light 111, incident light 121, and incident light 131 entering the microlens 103 from the same direction as that of the straight line 115 each are refracted by the upper surface 101 of the microlens 103 and focused onto the photoelectric conversion device 104. In this case, if the upper surface 101 of the microlens 103 lacks in refractive power with an increase in curvature radius, the lower surface 102 of the microlens 103 compensates for the refractive power to cause the incident light 111, 121, and 131 to enter the photoelectric conversion device 104. At this time, the refractive power of the lower surface 102 of the microlens 103 is larger than that of the upper surface 101 of the microlens 103. As described above, the microlens 103 can focus incident light onto the photoelectric conversion device 104 by using the upper surface 101 having a convex shape extending upward and the lower surface 102 having a convex shape extending downward with respect to the center plane 130.
Sony's new 400mm F2.8 G Master rounds out the company's commitment to provide a complete range of pro-level lenses to photographers who use the Alpha system. In this week's episode of DPReview TV, Chris and Jordan take this behemoth for a spin and share their first impressions of Sony's exciting new telephoto.
Dials and sliders and buttons, oh my! This modular set of editing controls hopes to improve your photo editing workflow – for a price.
The UK's recent heatwave has provided a glimpse into Britain and Ireland's history, revealing the outlines of ancient structures and buried features in the grounds of historical buildings.
The iPhone Photography Awards (IPPAWARDS), was founded in 2007, making it the longest running iPhone photo competition in the world. Now in its 11th year, the winners of the IPPAWARDS have just been announced.
Our technical evaluation of the Panasonic GX9 has included a trip to the studio, where we put its 20MP Four Thirds sensor in front of our standard test scene.
The Sony Cyber-shot DSC-RX100 VI earned high marks in our recent review, and we've revisited our collection of buying guides to reflect our final conclusions. Click through for links to our updated guides covering the best pocketable and long zoom compacts as well as the best choices for travel, which has a new winner (hint, hint).
Fujifilm has announced the XF 200mm F2 R LM OIS WR telephoto lens along with a matching 1.4x teleconverter. This weather-sealed lens - 'matte silver' in color with a bold green hood - has a total of 19 elements, a nine-blade aperture and five stops of shake reduction according to Fujifilm. The lens and teleconverter kit will be available in late October for $6000.
Fujifilm has updated its X-mount lens roadmap with three intriguing new models, which include 33mm F1.0 and 16mm F2.8 primes and a 16-80 F4 zoom.
Fujifilm's widest X-series zoom lens to-date, the XF 8-16mm F2.8 R LM WR, will hit the market in late November for $2000. The weather-sealed lens features ED, Super ED and aspherical elements along with a Nano GI coating.
We've seen different flavors of 360° cameras over the past couple of years, but the Vuze XR may be the first one that's designed to shoot both 360° spherical and 180° stereoscopic video in a single unit.
Huawei has launched the world's first photography contest with both AI and human judges. The contest began on July 12 and will run for 8 weeks. During this time, photographers can submit their images via a Facebook Messenger chatbot.
Fujifilm has announced the XF10, a premium compact camera with a fast 28mm equivalent F2.8 lens and 24MP APS-C sensor. This replacement for the X70 will ship in August for $500.
It won't come as a surprise to anyone that there are some unpleasant, predatory men within the photography industry. However, a long-form, extensively researched special report in the Columbia Journalism Review about sexual harassment is still a depressing, eye-opening read.
Is this the end? Nikon's UK and Japanese websites now list some of its KeyMission action cameras as discontinued.
Leica Camera AG is now an investor in Light, the makers of the innovative L16 camera. According to the company, the funding will allow Light to 'expand the reach of its imaging platform beyond consumer photography'
YouTuber ZY Productions has a video wherein he provides a succinct summary of how phase detection autofocus systems work, their benefits and their shortcomings.
The X-U is Leica's first ruggedized compact camera and is still the only waterproof camera on the market with a large APS-C sensor. That sensor sits behind a 35mm-equivalent, F1.7 lens, and we've taken it to the mountains and back to see just what it's capable of.
Gitzo and Sony have teamed up to launch a new tripod and L-bracket designed specifically for Sony α-series cameras.
There have now been seven variants of the Sony RX100 series, and at least six of them are still current models. Confused? Here's an updated look at their differences, and our recommendations among them now that we've tested the Mark VI.
The Kodak-branded 'Kashminer' Bitcoin mining scheme announced at CES has apparently collapsed, with Eastman Kodak distancing itself from the company behind it.
The software uses computational imaging techniques to boost detail and dynamic range in your images, and reduce noise levels.
As part of a promotional giveaway, Fujifilm Korea has released kimchi-flavored instant noodles wrapped in branding inspired by Fujifilm Provia 100 color reversal film.
The Leica Noctilux-M 75mm F1.25 ASPH is a fast, high-quality and decidedly heavyweight short telephoto prime lens, designed for use with Leica's digital M-series rangefinders. We've been grappling with it for a little while - take a look at our sample images.
70-200mm F4 zoom lenses may not get as much attention as their faster F2.8 siblings, but for many photographers these lenses hit the perfect sweet spot of price, performance, and weight. This week, we shoot the new Tamron 70-210mm F4 alongside the equivalent Canon and Nikon models to see how they stack up.
Blackmagic recently worked with Apple to develop Blackmagic eGPU, an external GPU that brings "desktop-class graphics performance" to the new MacBook Pro laptops with Thunderbolt 3 ports.
Lightroom alternative Luminar has received numerous updates across both its Mac and Windows versions, primarily improvements to existing features, as well as support for additional cameras from Fujifilm, Sony, Olympus, Panasonic, Canon, and Pentax.
Sony has quietly updated its RX100 V, bringing a couple of the goodies from the RX100 VI travel zoom. The updated RX100 VA gains a new processor and various firmware tweaks but misses out on the VI's other hardware improvements.
Apple has updated its MacBook Pro series of notebooks with 15in and 13in models that are claimed to be better for intense image and video editing. The company says the new models are the most advanced ever, and that they feature 8th generation Intel Core processors for faster performance.
According to sources familiar with the matter, Adobe will announce a full-fledged Photoshop version for the iPad at its annual conference in October.
The last day to place an order for Apple photo prints and related products is September 30th.