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Bionic Contact Lens May Lead to Overlay Displays
pfman writes "A University of Washington researcher has developed a
contact lens including circuitry and a matrix of LEDs. Although not yet a working prototype, this may be a foundation for terminator/robocop style overlay displays in which computer graphics could be superimposed on your normal vision. 'Building the lenses was a challenge because materials that are safe for use in the body, such as the flexible organic materials used in contact lenses, are delicate. Manufacturing electrical circuits, however, involves inorganic materials, scorching temperatures and toxic chemicals. Researchers built the circuits from layers of metal only a few nanometers thick, about one thousandth the width of a human hair, and constructed light-emitting diodes one third of a millimeter across.'" Kotaku notes that this has some obvious gaming implications.
Someone needs to read a book on how the eye works.
You only have receptor density for reading dead center in your eye. You can't put Terminator-style displays of to the side of your FOV, because you can only see motion and coarse detail off dead center.
Let's see, LEDs 1/3 mm across. My pupil is about 5mm, so that gives me a resolution of about 15 pixels across. Not so good, especially considering that to get that 15 pixels I would have to block everything else!
So how is it useful?
First: How are they envisioning powering a device like this?
Second: It's my understanding that human vision requires continuous eye motion to maintain visual perception. Try holding your eyeball still by (gently) applying finger pressure to it through your eyelid. You'll notice after a few seconds that your field vision slowly shrinks into nothing. If an image moves in perfect sync with your eyeball, isn't your brain likely to stop seeing it after a short time?
"Prefiero morir de pie que vivir siempre arrodillado!"
Isn't that safer? I don't want implanted chips or digital display in my body.
What about those of us who are squicked by the thought of anything getting near our eyes, let alone contact lenses?
While I have no expertise in the field, I've always assumed that we'd first see this with glasses. The classic HUD on aircraft is an image projected onto glass in the pilot's line of sight. I figured we'd see this when we either had a) some sort of transparent material with a tiny lcd grid so that wireframe graphics could be overlaid on the real world objects or b) VR goggles scaled down to the size of comfortable glasses with the world projected inside with the overlays on top.
The one other variant I could think of for a projector technology would be glasses with a tiny low-power laser tracking the retina and beaming photons into it.
Thinking about VR, though, it does make you wonder about the interrogation potential for completely controlling someone's environment. If you thought the Ministry was scary in 1984, just imagine the interrogator controlling your entire reality. There was actually a surprisingly good TNG episode where Riker was put through VR interrogation so that he would reveal something important. Each of those constructed realities seemed entirely convincing at first but as he started to find flaws, the reality would shatter and be replaced by something new. Scary.
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne
"Please stare into laser with remaining eye to recharge lens."
An LED at the surface of the eye's cornea/lens will flood the entire retina with light. It will appear as a red glare filling your field of view, and not as a little pixel of light. That is because the surface of the lens is out of focus, and so the wide angle light from the LED just spreads out.
If it were an array of lasers with tight beams, then it could work, but you can't make small lasers produce tight beams(due to the diffraction limit) without additional optics that couldn't fit under the eyelid.
They're pretty neat but if you look at the sun it bur#!2k4#$#$#_#_####[NO EYEBALL FOUND]
It's possible that they've thought of the issue of focusing the image.
One possibility would be that the display would use tiny lasers, to project very narrow beams of light at just a small group of receptors on the retina.
Different eye shapes/sizes would seem to make that difficult, but there's probably some way to do it, even if it means having to have "prescription" displays that match your eyes.
The Goatse virus for bionic vision.
At first, I was thinking that focus would be the main issue, since the middle of your lens is where all the light rays from the external world cross at an almost-point. Being so close to that (on the cornea), this lens might have focus issues.
But maybe not. All it really has to do is put incredibly small pixels there to colour (or obscure) the light from a given point. As long as pixels don't overlap too much (when out of focus), it could work.
I will be interesting to see how this develops further.
Love many, trust a few, do harm to none.
The lens system of the eye (cornea, crystalline lens and the overall air/liquid interface) is a kind of parallel optical computer that applies a function to both the angle of incidence and the location of incidence in order that light coming from points on a roughly planar region in the scene map neatly to points on the retina. Interestingly, if you look through a pinhole, you force the angles of incidence and the location of incidence to be correlated and the lens system of your eye becomes a spatial modulator - You can see the imperfections on the cornea, the shape of any cataracts you have and even the outline and surface details of the adjustable lens if it's a bit too small to span the pupil.
Anyway, the lens system is mainly geared for mapping angle of incidence to points on the retina. The location of incidence part is there so more than one point on the surface of your eye can contribute to gathering light. The parallax errors of the set of extra points is what causes the lack of focus for points outside the current scene focal plane.
Conventional helmet mounted displays work by using lenses to make their small-and-near displays appear big-and-far. In other words, every pixel in the display reaches your eye as a plane wave whose direction dictates the point on your retina that gets illuminated. The effect is ruined when the optics are bumped even slightly, so these HMDs are a real source of eyestrain. Just your eye moving around is enough to screw up the focus on units with very small display elements.
Retinal projection systems work by using detailed knowledge of the lens system of your eye to beam pixels at different parts of the cornea in a way that sort of bypasses the natural function of the lens system. The projector is far too close for the eye to focus. If you could, you'd find the projector nothing more than a tiny light that occupies only a small point of your vision. RPs work by being way out of focus (so they appear large in your field of vision) and achieving their sharpness by using the parallax errors as a feature - something that can only be done with small, tightly controlled laser beams.
A contact lens display system would require the ability to emit thousands of precisely aimed beams or plane waves. At the cornea, the location of the emitters is almost irrelevant. If they emitted spherical waves (as LEDs tend to do), the patch of light from each emitter would span a large part of the entire retina. The 7x8 display in TFA would appear as a 7x8 Photoshop image subject to something like a Gaussian blur of a radius close to the size of the entire image (but on a much larger canvas).
That's where holography comes in. To avoid needing detailed knowledge of the eye, the holographic system uses millions of simple emitters programmed to effectively generate the required plane waves through constructive and destructive interference. No extra lens system is required.
The computational power might be a wee challenge, though. Otherwise the holographic contact lens system is elegant in its simplicity.
Blancmange