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Lens-Free Flat Cameras Make Use of Pinhole Technology (npr.org)
RhubarbPye writes: As reported on NPR, "Engineers in Texas are building a camera that can make a sharp image with no lens at all." By incorporating millions of individual pinholes with photoreceptors and postprocessing software, this camera system has been reduced to minimal thickness. Cameras in the wallpaper? A new phase of wearable cameras? What other applications for this technology could be developed?
Looks like someone decided to put their money into a hole.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
Poor sufferers of paranoid conditions, will freak at this. Now their wallpaper might be spying on them...
A/J/A peepshow lens, is nothing to sneeze at.
So, let's see if I get this right. They rediscovered something, that everyone from the 1990's and 80 years prior learned to make as part of science class...and simply applied modern technology to it.
No, you didn't get it right. But that's not surprising, clearly you didn't read the article.
If you want news from today, you have to come back tomorrow.
This technology has many holes. It looks like there is no limit of how many holes you can have. I would imagine that with enough holes you get super accurate photos from space. And most likely it will be much cheaper.
TL;DR. Most uncooled camera chips give you maybe 10 or 11 bits of dynamic range, and light is subject to Poisson noise, meaning the brighter a pixel, the noiser it is in absolute (not relative) terms. If you have to solve a big giant matrix inversion to do the job of a collimating lens, you're composing each pixel as a sum of many others instead of just itself, some of them being way brighter than the reconstructed image, meaning your reconstructed pixel is always noisier. Cool idea, and certainly has its applications, but the best images will always come from big fat optics.
I suspect that if you put a lens on it, you would end up with a light field camera.
aaaaanyways... this is wikipedia on light field camera: "A light field camera, also known as plenoptic camera, captures information about the intensity of light in a scene, and also captures information about the direction that the light rays are traveling in space. One type of light field camera uses an array of micro-lenses placed in front of an otherwise conventional image sensor to sense intensity, color, and directional information. Multi-camera arrays are another type of light field camera. Holograms are a type of film-based light field image."
which sounds almost exactly like a variation of this. it's the same exact concept.
world was created 5 seconds before this post as it is.
Seriously, you need to get some help.
Obviously you are scared of your feelings for members of the same sex, you should get some help in accepting this and you may find a path to a happier lifestyle.
It seems you also suffer fear from the feelings of attraction you have for people of different races. Embrace these feelings, they will also lead you to a more comfortable and fulfilling relationship one day.
Nothing in the article talks about what the resulting aperture is. To get a reasonable exposure time, you need to capture adequate light. Cameras in cell phones already suffer because their lenses are too small to capture enough light. Is this scheme worse because it lets less light through or better because a larger "lens" is practical?
But based on the blurry, grainy photos they have taken with it so far, i am not terribly impressed. Add a few MM of thickness onto it, and a modern cellphone camera can take photos miles better than that thing. (without the costly computations as well)
What would be interesting is if such a sensor array could efficiently and wirelessly tether itself to the image processing engine. The potential surveillance applications are mind boggling.
Nothing evolves faster than the word of god in the minds of men who think themselves divinely inspired.
Combine your vdu and a camera and you have a much better Skype/spying device.
with the same principle.
Except having a lens reducing the amount of holes significantly.
Generally a pinhole camera is very light insensitive due to the small amount of light let in by the pinhole, but multiply the number of pinholes to amplify the image and use a super sensitive sensor gathering from each pinhole, and it seems like it would yield some amazing results.
http://www.kshitijmarwah.com/index.php?/research/compressive-light-field-photography/ (From MIT Media Lab)
I see all of the photos in the article were taken with a conventional camera, complete with lens blur.
First application before useless wallpaper camera should be dual camera vision system as stereo matching with lens-less camera should be easier.
Actually it's more like the compound eye of insects, but 'wired' differently.
Freedom = (Meaningful - Coerced) Choice != (Speech | Beer^2), and sad sock puppets' bad mods avail them naught.
So make a headband 360 degree camera to capture video you can view with your VR headset. Also, make police officers wear these instead of the silly badgecams they currently use.
...will be your screen. In a video call you will be able to look at the other party in his/her eyes and it will not appear like you're reading something else.
Coded aperture imaging (CAI) (Mertz and Young, 1961; Dicke, 1968) has matured as a standard imaging technique in X–ray and Gamma-ray astronomy. It is capable of combining high angular resolution with good photon collection efficiency by using a mask consisting of transparent and opaque elements placed in front of a position sensitive detector (Figure 1).
So is the only innovation here using more pinholes, more pixels, and more processing than were around in the 1990s?
Cameras like this don't let you overcome the diffraction limit for a given overall detector size.
I think the "micro mask" is the lens array. It already is a light-field camera.
I can't wait to see what these things start to be capable of as technology progresses to assemble the micro structure and we get over the computational overhead
j'ai découvert une démonstration vraiment admirable (de ce théorème général) que cette si
BAN THIS TROLL AND ITS IP ADDRESS
this is worse than anything APK posted
Is this scheme worse because it lets less light through or better because a larger "lens" is practical?
Currently, it's worse (TFA mentions quality similar to first gen webcams).
But indeed, that technology is really scalable. TFA muses with large surface flatcams.
(They mention walls of it. Or boxes/cylinder in the middle of which you put an object, etc.)
So the whole back cover of a smart-phone could be a giant pinhole array.
Such a large surface even if covered with only pinholes (and even if some of the hole might get obscured by fingers holding the phone) would gather much more light and information and could produce better image. Exactly as you say : "a practical larger len" but taken to the extreme
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
So, let's see if I get this right. They rediscovered something, that everyone from the 1990's and 80 years prior learned to make as part of science class...and simply applied modern technology to it.
No, you didn't get it right. But that's not surprising, clearly you didn't read the article.
What? Even TFA itself mentions that the researcher decided to go back to the classical pinholes as inspiration:
To design their camera, Baraniuk and his colleagues looked to the past for inspiration.
"Back to really the very first cameras, pinhole cameras," Baraniuk says.
Pinhole cameras have been here for quite a while. According to some scholars, they were first described by the Chinese philosopher Mo Ti around 400 B.C
Basically they've taken the pinhole camera, and decided "We have computing power !"
Instead of putting just one camera (which would definitely NOT gather enough light at this size), they're massively parallelized it. They've put millions of pinholes camera on the chip and are using post processing to reconstruct the final image out of the tons of tiny pinhole views.
In away their doing exactly what light field photography does, except sans the micro-lens array usually associated with the technology. They've put a pinhole mask instead.
But the parent poster is right, the research have decided to take a well known old trick (the century old pinhole camera) and put a new spin to it (apply tons of computing, thus using tons of pinholes in massive parallelism, enabling to do something like light-field photography, but with no lens at all).
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
TFA:
To design their camera, Baraniuk and his colleagues looked to the past for inspiration.
"Back to really the very first cameras, pinhole cameras," Baraniuk says.
Pinhole cameras have been here for quite a while. According to some scholars, they were first described by the Chinese philosopher Mo Ti around 400 B.C
No, you didn't get it right. But that's not surprising, clearly you didn't read the article.
Apparently I did. How the hell your comment got to informative I have no clue.
Om, nomnomnom...
The Fly... Anyone?
http://rdhorrorproject.blogspot.com.br/2010/10/film-44-fly-1958.html
I assume that you still have to make the surface with all the pinholes in, a little convex. If only to not just capture the same square cm in front of the lens a thousand times.
Religion is what happens when nature strikes and groupthink goes wrong.
They didn't rediscover it. They knew about it all along, but figured out a way to actually make it useful in this application. So your claim was incorrect.
No. They applied new technology to something they already knew about.
A pinhole camera is educationally interesting but not much use for practical purposes. You simply don't get enough light coming though. It's easily solved by optics. Most cameras use a lens to squeeze more light through the aperture. But this requires a certain thickness. Not a problem if you can afford a few CM of thickness, but unsuitable for flat cameras.
You can also solve the problem by using lots of pinholes. But if you use a single CCD, you get interference from lots of similar but different images. So you need to use some pretty sophisticated computer processing to unmerge these images.
ShashDot goes to S@$@% lately, what is happening with this site?
What is this stuff? It's hard to read on a mobile browser, it shows everything..
Hey op you have an issue with African Americans?
Actually, I remember reading this in a dead-tree scientific american in the (irc) 70s. After reading TFA, it's exactly the same thing. Hope they don't get a patent on it :-)
"Transparent" is a shit show that trades on every stereotype going. A man in drag is NOT a transsexual.
A pinhole camera is more than adequate for taking pictures of eclipses of the sun, etc. It's also good enough for taking stills (longer exposure time) or objects lit with a very bright light (like a flash, maybe?).
"Transparent" is a shit show that trades on every stereotype going. A man in drag is NOT a transsexual.
To design their camera, Baraniuk and his colleagues looked to the past for inspiration.
That's effectively rediscovering it.
Om, nomnomnom...
So, nothing like it at all, then?
Interesting work with a lot of unobvious possibilities. "Lensless" is a little misleading. Pinholes are just the center circle of a zone plate. Zone plates are lenses that work by diffraction instead of refraction. They look like a bulls-eye (see http://www.eastjesus.net/tech/... for a quick and simple primer). The diameter of the hole determines the focal length - hence too big OR too small leads to fuzzier images. The have a couple of big drawbacks - the focal length is a function of wavelength hence objects in the image have rainbow edges and the aperture of a focused pinhole is small (the f-stop). The effective f-stop can be increased at will by adding additional zones around the pinhole but zone plates that work by blocking areas can only achieve efficiencies of around 10%. That can be improved to around 90% or more by replacing the opaque zones with tapered phase-shifting zones. Back in the mid 1980's I worked with a similar technology using arrays of zone plates which we called Integral MicroOptics. We used arrays of micro-zone plates (and pinholes) to capture image data over large sheets (hence from many angles at once) and then reconstruct that data with full parallax in 3D and color, both stored and in real time and sometimes with some optical computing applied - all using passive devices! They were the equivalent of full color holograms using a subtractive technology instead of an additive one, hence no lasers were required and the more diffuse the light the better. It was amazing what could be done with thin flat sheets of plastic and printing but the technology of the day was too crude to get very far. Today much more could be achieved. If interested you can see the original paper from 1986 at http://www.eastjesus.net/tech/... (with updated graphics and a link to the original) and http://www.eastjesus.net/tech/... for some images created using the technology at that time.
Single pinhole cameras have severe quality limits. Make the hole too big and sharpness is inversely proportional to the diameter of the hole. Make the hole too small and sharpness is proportional to the size of the hole, and the amount of light is reduced also. For best sharpness there's an optimum pinhole diameter { 1.9 * sqrt ( f * l ), where f is focal length and l is wavelength }, and the results even at the optimum aren't very good.
Multiple pinholes offers a theoretical way around the diffraction limit. If I understand the concept correctly, this is a "synthetic aperture" technique.
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and the results even at the optimum aren't very good.
You might be surprised if you do an image search for "photos taken with a pinhole camera."
"Transparent" is a shit show that trades on every stereotype going. A man in drag is NOT a transsexual.
They're stylistically interesting, but don't have constant brightness across the image and have some pretty quirky distortion; which I appreciate looks good, but is usually the sort of thing photographers want to avoid.