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.
Sep 22, 2017
Sep 21, 2017
Sep 19, 2017
Sep 15, 2017
|Patrick Finds Inner Peace by ecastellon|
from Your best photo of the week!
|Forks by Kukla|
from Arranged everyday objects
The new iZugar 3.25mm F2.5 super fisheye lens offers an insane 220-degree angle of view. That means it can basically see behind itself... good luck keeping your feet out of the shot.
You'll laugh, you'll cry, you'll remember that time you took a picture of the frozen pizza baking directions.
A Craigslist poster has discovered the worst possible way to photograph a car: taking pictures of pictures displayed on a cracked and scratched up smartphone screen.
With the iPhone X coming out soon, the title probably won't last, but the iPhone 8 Plus is officially the best smartphone camera DxOMark has ever tested, and the iPhone 8 is second.
Kodak's new Facebook Messenger chatbot is trying to bring back the 'Kodak Moment' by digging up your old social media photos and trying to sell you prints and custom coffee mugs.
Affinity Photo for iPad was touted as "the first full blown, truly professional photo editing tool to make its way onto the Apple tablet." This update makes it that much more convenient.
Yashica has released a new teaser video, and this one claims they'll be releasing an "unprecedented camera" in October on Kickstarter. Ready... set... speculate!
Storage solutions company Synology has just released its very first 6-bay NAS tower. Combined with the DX1215 expansion units, it can hold and control up to thirty drives.
We're always expanding our collection of product overview content, and we've just added videos for the Canon EOS 6D Mark II, the EOS Rebel SL2 and EOS M6.
The venerable Canon PowerShot G1 was announced seventeen years ago this week, marking the start of a line of enthusiast-focused compacts that's still alive and kicking.
Super macro photographer Can Tuncer captured these incredible close-ups of a single peacock feather using a special setup and three different microscope lenses.
After successfully crowdfunding the Biotar 75mm F1.5, Oprema Jena is at it again. This time they're bringing back the Biotar 58mm F2: the world's only lens with a 17-blade aperture.
Adobe's move to a subscription model is treating it very well indeed. The company has posted record revenue for the second quarter in a row, hauling in a mind-boggling $1.84 billion.
More details have emerged about the potential sale of Blackstone's 45% stake in iconic camera brand Leica.
Popular mobile editing app Snapseed just got a major update that includes a new interface and 11 new presets for both Android and iOS, as well as adding the Perspective tool to the iOS version.
It might sound like a strange idea, but taking macro photos of boiling water can actually result in some really cool photographs. A good photo experiment for a rainy day.
The database was created to "break with the narrow lens through which history… has been recorded" by equipping those who commission photography with "the resources to discover photographers of color available for assignments.
Lensbaby has released two new optics for their special "optic swap system." The Lensbaby Sweet 80 Optic gives you that trademark sweet spot of focus, while the Creative Bokeh optic gives you 9 different drop in aperture plate options to play with.
TechCrunch has already posted their review of the upcoming iPhone 8 (not yet the iPhone X), and they're calling it "a look into the augmented future of photography."
Affinity Photo is a $50 photo editing software with no subscriptions. That's it – pay for it once and you're done. And we think it's actually pretty darn good.
Instagram is currently testing a major change to the app's profile layout: replacing the 3-photo across grid with a 4-photo grid... and some users are NOT taking the news well.
A report by USSRPhoto is shedding some light on the return of the famed Zenit camera brand. It seems the full-frame mirrorless camera they're working on will be made in part by Leica using components from the Leica SL.
According to a reliable Korean report, Samsung is developing a smartphone sensor that's capable of super slow motion. Translation: Samsung's next batch of Galaxy smartphones may be able to shoot 1,000fps.
This simple photograph of a seahorse and Q-tip has taken the internet by storm. We spoke to photographer Justin Hofman about how it was captured, and what it means to him.
After a massive leak last week, Profoto has officially debuted the Profoto A1: the company's first on-camera flash system that they're calling "the world's smallest studio flash."
"When the first hyperfocal distance charts were designed, someone decided that an acceptably sharp background contained some blur — enough to notice in a medium-sized print [...] After that point, nearly every other hyperfocal chart followed suit."
The Canon EOS Rebel SL2 (also known as the EOS 200D) is the company's impressively compact entry-level DSLR. Packing a 24MP APS-C sensor, DIGIC 7 processor and Dual Pixel AF, it promises a lot of bang for the buck. And while not mind-blowing, it handles most tasks very well.
Correct these four common composition mistakes and your photos will be more balanced, tell a better story, and lead your viewer's eye where you want it to go.
The rugged, compact 360° action camera Kodak unveiled at Photokina in 2016, the Kodak PixPro Orbit 360, is finally available in the United States.
iOS 11 launches tomorrow, and it'll save all of your pictures in a new high efficiency image format called HEIC. Fortunately, there's now a converter that will let you turn those photos back into JPEGs.