Lytro site hints how it works:
Light Field Capture
How does a light field camera capture the light rays?
Recording light fields requires an innovative, entirely new kind of sensor called a light field sensor. The light field sensor captures the color, intensity and vector direction of the rays of light. This directional information is completely lost with traditional camera sensors, which simply add up all the light rays and record them as a single amount of light.
NYT writes:
"The Lytro camera captures far more light data, from many angles, than is possible with a conventional camera. It accomplishes that with a special sensor called a microlens array, which puts the equivalent of many lenses into a small space. “That is the heart of the breakthrough,” said Pat Hanrahan, a Stanford professor."
WSJ writes:
"A key to Lytro's strategy is to use the increasing resolution found in the image sensors in conventional digital cameras. The company developed a special array of lenses that fits in front of image sensors and helps break the image apart into individual rays, along with software to help reassemble and manipulate it.
Lytro lists other benefits. For one thing, since images are focused after the fact, users don't have to spend time focusing before shooting. Nor do they have to worry if they wound up focusing on the wrong thing.
The technology works in very low light without a flash, Lytro said, while 3-D glasses can add a particularly vivid effect—simulated three-dimensional images that users can adjust to show different perspectives."
Lytro founder and CEO, Ren Ng, 31 explained the concept in 2006 in his Ph.D. thesis at Stanford University, which won the worldwide competition for the best doctoral dissertation in computer science that year from the Association for Computing Machinery. Leading Lytro's technology team are Kurt Akeley, formerly of Silicon Graphics, and Adam Fineberg, formerly chief architect for the WebOS software developed by Palm, which is now part of HP.
So far Lytro has raised $50M from NEA, K9 Ventures, Greylock Partners and Andreessen Horowitz. Lytro isn't disclosing details before releasing its first cameras later this year, but Ng says their pricing will be competitive with today's consumer cameras. Ng gave 15-min long interview to TechCrunchTV:
WSJ points to possible Lytro's competition: "Adobe Systems Inc., which has developed prototype light field cameras for research purposes. Besides the technology departments of big camera companies, other startups are pursuing related technology... One is Pellican Imaging Corp., which in February announced a prototype of what it calls an array camera for use in mobile devices."
Update: PR Newswire: Sequence, a creative development agency based in San Francisco, announced that it is Lytro's branding and user-experience partner, and helped them with all aspects of their brand.
"Sequence has been a valuable partner," said Ren Ng, CEO and founder of Lytro. "They quickly understood the complexity and potential impact of our new technology and have helped us create a powerful yet simple brand experience that really resonates with our target audience."
I am very skeptical about the acceptance (usefulness) of this technology by the consumer market. It will be fun to play with it for a few minutes though. What is not said is that you basically trade resolution for the refocus capability. So even if you have a 12 MP camera, you may end up with a VGA picture. Of course its another question whether you really need those 12 MP in the first place. I wish Ren all the best, but please think what else this technology can be utilized for.
ReplyDeleteThey've been all over the news this week..Wonder who makes the sensor for their camera..They must be using cmos sensor and a special microlens array..
ReplyDeleteThe amount that you can refocus depends on how much resolution you trade off, converting spatial resolution to angular resolution. That doesn't work well on small format sensors found in camera phones.
ReplyDeleteThe latest algorithm does not sacrifice resolution of the image sensor to produce the light field. That was the original technology.
ReplyDeleteIs this EDOF part 2?
ReplyDelete"The latest algorithm does not sacrifice resolution of the image sensor to produce the light field." The constant radiance theorem begs to differ. In a traditional well-focused lens, all of the rays within the f/stop of the lens are focused onto a pixel assuming your lens resolves beyond the Nyquist limit. In a light-field camera, the micro-lens will spread this light over many pixels, reducing your SNR. There is no free lunch.
ReplyDelete"In a light-field camera, the micro-lens will spread this light over many pixels, reducing your SNR. There is no free lunch."
ReplyDeleteand Lytro's claim:
"The technology works in very low light without a flash"
Are these two statements contradictory?
If the camera is large, the sensor is large and the aperture is large and you produce VGA-sized images, then you could distort this to say that the technology performs well in very low light. For a given format and output resolution, a focused camera with the same main lens aperture will always do better. There is a noise penalty with the arrangement of the data and an overhead loss in the number of usable pixels associated with this approach.
ReplyDeleteLikewise, for any particular focus setting, a focused camera produces a higher quality image. The only time you get an improvement in low light is when you compare it to something that has a smaller sensor or aperture. It is not the technology that works well in low light, it is a large sensor and large aperture that work well in low light. You can use a larger aperture in a normal camera than their camera which is fixed an limited. Low light performance is always better in a normal camera unless it is stopped down.
How does this technology compare with a high frame rate sensor + fast autofocus? Does any camera have such a mode that allows one to set multiple focus point and then takes multiple pictures with different focus?
ReplyDeleteI would also be interested in a camera that takes multiple images at high speed, with different automatic aperture steppings so that I can create an HD image out of it, offline
ReplyDeleteThe first tag line for Photobit was "Leading the Active Pixel Revolution"
ReplyDeleteI think Lytro's ad men are not so inventive.
They may be better off reducing their BOM and licensing to the CE players, at least it seems that way.
ReplyDeleteThere is a much better refocusing technology that is designed fro mobile phone camera modules. I saw a live demo that some guy showed at Barcelona. The company was called linx-imaging or linx-technologies. They showed the refocusing with very high res on a Android device.
ReplyDeleteit would be good to have that feature on my phone and not pay 400$ to carry around a 1 Mp box.