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Laser Powered Virtual Display
Tedger writes "The Feature has an article discussing an interesting portable display system developed by the University of Washington. Unlike your traditional mini displays mounted in glasses this system has no display, it is a 'virtual' display created by lasers and microscopic fast moving mirrors. The image is in fact printed onto the retina and has feasibly a infinite resolution. Can anyone say true VR?"
I for one welcome our retinal destroying overlords.
First post?
Laser images printed on the retina? what are the safety concerns with this? i would think "burn in" would once again be a serious issue.
Puts hiro protagonist's display to shame (his required glasses I think) Wonder how long before someone tried to snowcrash a person through it :D
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Even if they do work out all the bugs in the system, it's still only a step toward true VR at best. Without ways to also stimulate all our other senses, this will be more akin to TV than VR.
Do not look into laser with remaining eye.
# cat
Damn, my RAM is full of llamas.
Weren't there glasses with LEDs projecting on your retina already? Those certainly sound safer than lasers.
Back in 1999.... I haven't RTFA, much less compared the two. Somebody has?
I recall researching such "direct imaging" devices back in 1995; they were going to be the next great thing in VR, back when virtual reality was still a meme. What is neat is the idea of wide integration, though safety issues even with low power lasers would, I imagine, remain a problem.
As an analogy, consider headphone use vs. speakers. In the headphone case, you can easily damage your ears without even noticing you're doing it by having it a tinsy bit loud, while the speaker output makes it much harder (I imagine due to all that feedback to the rest of your body!) Similarly here, you are probably imaging on a limited part of your retina, which may make your eyes dilate open too much, and develop small damage over time, etc.
Either something incredibly dangerous (Do Not Look Into New Monitor With Remaining Eye) or amazingly trippy (with Pink Floyd playing in the background).
True VR True VR!
What do I win?
can anyone say "can anyone say?" yes, anyone can, and its losing its punch.
I recently read a book "The Visionary Position" which detailed the university of washingtons virtual reality lab and all of the various spin-off companies.
It wasn't a bad book, but they've had these things since the mid-90's -- just hard to find an appropriate market I guess.
"But actually trying to use m4 as a general-purpose langage would be deeply perverse" --ESR
After all the obstructive heads up type units we finall have one with the potential to co-exist with our normal field of vision. The "augmented reality" could give us new ways of seeing the world, with a 3-d overlay on reality. In the article they mention and automotvie expert system which will give the user a visual overlay of the system their looking at.
Also it should give you the ability to use PDA's in a private fashion while still having a large view. In fact, this could redefine the PDA format, instead of the little notepad style device. Just gotta get the production levels up, cost down, so it's more affordable than the $4000 price tag.
Bacardi + slashdot = negative karma.
where do the friggin sharks come in the picture?
10 ?"Hello World" life was simple then
Didn't we see this already?
Y'see - porn CAN make you go blind!
--- Egads, I glow in the dark!
Would be if, since they're already sticking us with a laser beam in the eye, was if they could track eye movements.
This way we coul play tetris (or by that time Grand Theft Auto on a cell phone) just by tiny eye movements.
It's all fun and games until someone burns an eye out.
The resolution depends on the ability to steer the mirror in a very exact manner.
Mounting it on glasses makes it a nontrivial task.
I mean, if I remember my optics correctly, the way the cornea/lens assembly works is that all incoming light originating at the same point out there ends up in the same spot on the retina, regardless of which path they take through the lens. This is what enables us to see a clear image.
Although it has certain other intersting proerties, laser light obeys normal refraction.
Yet they talk about suåperimosing the image on the normal view. How can you project to any other part of the visual field than the area where you see the projector?
Anyone know what the trick is?
sudo ergo sum
Hmm. The system seems limited at the moment to only red, and what seems to be 1-bit color. I sense a comeback of ASCII porn!
It does, though, bring a whole new meaning to "do it too often and you'll go blind"...
I used to work for a company that produced a High Resolution Display that used mirrors to steer a red or blue laser beam onto a sheet of photochromic film - the blue laser would permanently write on the film - the red laser could be used for drawing small amounts of vector graphics - a cursor, or a few characters of text. Doing complex graphics in vector mode when the persistence of the human eye is less than 40ms will require the mirror to be scanned at very high frequencies
I'm not too worried about safety: if you limit the maximum power output of the laser, even in case of short-circuit, it shouldn't be a problem.
This is a technical problem, engineers have been good at solving those.
The human limitations may be much more difficult to overcome: show a 'static image' to a moving man and you have a problem: eye say static, inner ear say 'you're moving' --> conflict --> sea-sickness!
Well, it obviously can't have an infinite resolution, the best it could get is 1:1 mapping with the rods and cones in the back of your eye.
And of course this is old fashioned analog technology, just like in a CRT firing beams of electrons in the rough direction of dots in the phosphor, it's not accurate. What you need is a direct digital plug in the back of your optic nerve!
Jolyon
Please read my Canon EOS tech blog at http://www.everyothershot.com
Laser light is fundamentally different from natural light ... its a coherent group of photons; all approximately in phase, traveling in the same direction with roughly the same energy. This stuff isn't normally encountered in nature. Its hard to say what long term exposure to this sort of radiation is going to do to sensitive tissues like those found in human eyes ...
I'm being general here; not saying it couldn't be safe. In any case its completely different from looking at light scattered from a screen, staring at a light bulb filament, or seeing an image formed by separate little light-sources (pixels) on a CRT.
They must have diffraction/interference problems stuffing a laser straight into an eye like that?
6 years ago or so they where working on this type of system here at the university. I had the pleasure of trying it out (after signing a disclaimer of course :). At the time is was red only, but very very cool. They couldn't focus the beam depending on what distance you were focussing on. So the images they projected where sharp only at one fixed "focus distance" for your eyes.
They could produce a low resolution overlay image over what you were actually looking at. They could only produce very simple line drawings floating in the air. But still.. you had your own private (head ache inducing) lasershow.
I would think that this design would require the user to always look directly forward. Otherwise the laser wouldn't hit the same spot when the user looked slightly to the side. The visual distortion that this would cause would probably make you pass out. In order to really make it work you would probably need to track eye movement as well. Although this is possible, it seems like it would be error prone and would make the system too expensive for consumer use. The bottom line is that unless they place the laser emitter right on your cornea, any eye movement would cause distortion and make the user very dizzy. The further the distance between the emitter/mirror and your cornea, the bigger the impact of even tiny eye movement.
BBC has an article on it as well.
t m
http://news.bbc.co.uk/1/hi/technology/3647437.s
Actually, this is a well documented issue if the display uses IPv4. (Scroll down to item #3).
Okay, just a few things about this and some problems.
... bah, it's enough already.
Microvision is the company doing this.
What about saccades? When the eye moves rapidly over a long angular direction (which it does in tracking objects or changing your view) or a short angular direction (a.k.a. microsaccades, which happen multiple times a second), you get blurring which is normally suppressed by the visual attention system.
When you do saccades across long persistence displays like LCDs, you will not see any major aberration as the light source effectively stays on. When you saccade across medium to short persistence displays (P21 phosphors for short, your regular TV or CRT for medium), it is possible to notice that there is either a shearing or tearing artifact.
TV/CRT displays are scanned left-to-right at (say for 640x480 VGA at 80 Hz) 480*80=38400 times per second and scanned slow...ly up-to-down 80 times per second followed by that quick scan back up. Well you can try this at home (TV's at ~60 Hz show this a little more easily than most of our CRTs which are set at a less-likely-to-appear to flicker refresh of >80Hz):
look at an object to the left of the TV screen. Then rapidly switch what you're looking at to the right side of the TV screen. The image of the TV will no longer look rectangular but like a shortened-horizontally and sheared (top to the leftish, bottom to the rightish) parallelogram. If you do a right-to-left saccade, the image will appear longer horizontally and top to the rightish of the bottom.
Now the interesting thing happens with up-to-down saccades: if you go up-to-down at slower than or close to the same angular velocity as the scan line (depends on how close you're sitting to the screen) goes down the screen, the projected image will appear SHORTER-UP-TO-DOWN and if you actually match the scan-line's downward angular velocity, the TV image will seem to just be a poorly set up XF86 display of one pixel in height.
If you have an effectively ZERO-PERSISTENCE direct write display, since the laser is being used to draw directly on the retina (or to project on a screen) rather than an electron-train hitting chemicals causing them to phosphoresce with a certain limited time before they stop glowing (PERSISTENCE...), then fixation has to be maintained or the illusion of motion based on the projection's position is destroyed. Laser projection systems try do multiple lines scanned at once or other fancy projection scan patterns rather than the usual cathode-ray-gun approach, but the saccade problem continues to be an issue.
The saccade errors are the big to-do with projective laser displays for visible wavelengths, regardless of whether they are projected onto a screen or direct write onto the retina.
The other problem is
These guys have been at it for quite awhile with some nice results.
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No matter how thin you slice it, its still baloney.
One of the problems with these devices is that they tend to end up classified as medical devices due to the tight integration with the retina.
This stuff is cool, but I don't see it becoming available in the U.S. any time soon. I would worry about a bad capacitor or something that suddenly released an hour's worth of exposure in a microsecond and fried my retina. Somebody with more engineering knowledge of these systems may know whether that's impossible or not, but it will always represent a consumer concern, I imagine.
If your bitterest enemies are people who hack the heads off civilians, then I would say you're doing something right.
Unless there is an separately calculated image for both eyes, and a head tracking unit, it will not appear like an object is "virtually in front of you". Without these two things, you simply have a 2D overlay on your regular vision. The separate images are required to make your eyes focus at a particular distance, the head tracking so that when you walk rightward, the object goes leftward, etc.. Perhaps the technology is there, but not described in the article...
Audio we're coming close to. A really good home theatre system with proper placement can be quite realistic.
/.), and others, I'd imagine it's just getting the nerve attachments/impulses right that is holding us back for now.
Smell... well they're working on smell-generating devices but there's not really a "virtual" way to do this. You can't exactly plug into your olfactory to stimulate the nerves there.
Touch, again... too much to cover and no proper way to stimulate, and taste may go along with smell.
Right now, we're doing a lot better at covering vision and sound. The only way we'd go too far beyond that would likely be direct interaction with the nerves/brain. If you're worried about the laser damaging your eyes... how do you feel about plugging your brain into doom 8?
Still, some day it's likely to go that path. Likely it will start with optical/cochlear implants for the blind/deaf, progressing with limb replacements etc with direct nerve connections that can feel and move realistically. Actually, with things such as "dracucell" (blood powered batteries, mentioned long ago on
At the moment, I think I'll stick with my laser-glasses and 3d projected surround... any improvements on such are of great benefit as is.
Besides, if we were wired for smell/taste, goatse pranks could be 100x as bad if you stumbled into the wrong URL with your sensors on.
I'm sorry to spoil poster's joy, but aren't these and
these folks already selling such devices for many months, if not years?
Computers make very fast, very accurate mistakes
"One can watch the Sun in a telescope exactly two times in a lifetime. First - with left eye, second - with the right."
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