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Video Projector on a Chip?
Posted by
ScuttleMonkey
on Wed Aug 23, 2006 06:31 PM
from the new-annoying-cell-phone-gadgets dept.
from the new-annoying-cell-phone-gadgets dept.
Stile 65 writes "Cornell researchers have made a 0.2mm-squared mirror mounted on carbon fibers that can oscillate at 2.5KHz, 'caus[ing] a laser beam to scan across a range of up to 180 degrees.' These can be mounted on a chip, and in combination with lasers, arrays of such mirrors on a chip can be made into a video projector. From the article: ''"It would be an incredibly cheap display," [Cornell grad student Shahyaan] Desai said. And the entire device would be small enough to build into a cell phone to project an image on a wall."' This display is made possible because of the innovative use of carbon fiber instead of silicon in MEMS. Unlike a standard DMD, this type of device would have one mirror per scanline, not one mirror per pixel, allowing the chip to be much smaller."
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Wow! (Score:5, Funny)
Prediction: (Score:5, Interesting)
Re:Prediction: (Score:4, Funny)
Parent
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Problem solved.
manufacturing efficiency of carbon fibre? (Score:3, Informative)
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And that's why LCD displays cost about a buck.
What is the manufacturing efficiency of carbon fibre?
The carbon fiber in a thirty dollar fishing pole is measured in kilometers. In this device the carbon fiber elements are measured in microns. Only one device per scanline is needed.
As per my first sentence generally manufacturing costs swamp materials costs when building per unit, but as per my fourth sentence a 1024x768
At least CRTs had phosphor "memory" (Score:5, Interesting)
2.5 KHz is a pretty high refresh rate (Score:3, Informative)
Re:At least CRTs had phosphor "memory" (Score:4, Interesting)
-V
Parent
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Minor correction... Film is recorded at 24fps, but each frame is then projected/displayed twice, so the refresh rate is 48 frames/sec.
Most people's eyes would indeed have a problem with a 24 frames/sec refresh rate.
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No^2 (Score:4, Informative)
and
No, they are missing one thing: Brighness still does need power. While lasers have become more efficient, and the lifetime of blue ones doesnt suck anymore (thanks to lots of $$ invested by storage companies), there is still physics to play with:
with a perfect display screen, you need at least 15W (rough estimate, dont care to converte the lumens right now) of photon power per m^2 to get a usable picture.
That of course would mean you would need those 15W in Laser emitters. As tubes are prohibitively expensive, that means diods. Diods are a _bit_ heat sensitive (they die like flies if anything is not to their liking), and i havent seen 5W or higher diods without a good cooling solution (because they will still protuce 2 times as much heat as light, and that in a very small volume.
Not to mention the little fact that a single 1W blue laser diode right now would be more expensive than a HD-Dlp beamer (plus it would degrade quickly to unusability).
No ^ 3 (Score:2, Interesting)
Since the image has a fibre per scanline you can use lots of low power laser diodes.
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and society marches backward... (Score:5, Insightful)
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Actually, it is just what we need, if the goal is to replace personal computers with cell phones. Imagine 10 or 20 years from now, ugly beige boxes have gone the way of the VCR and everybody just carries their "PC" with them in their pocket wherever they go. Wireless Internet access is available everywhere, of course, and while you can still use the small screen on the train, yo
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Incoming call... (Score:5, Funny)
*display activates*
Princess Leia: Help me Obi-Wan Kenobi, you're my only hope!
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ZARDOZ!!! ZARDOZ!!!
Vortex 4 Surplus
1 grainz
6 winez
oblig. Star Wars Comment (Score:3, Funny)
It will be like this: (Score:3, Funny)
or
"Help me Kemo_by_the_kilo, you're my only hope is what your woman will say with your new prehensile penis!"
What about power? (Score:2)
Re:What about power? (Score:5, Funny)
One powered by a Dell laptop battery.
Parent
Sweet, now I can (Score:4, Funny)
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Light Density Sounds Like a Concern (Score:2)
Devil's in the details... (Score:4, Insightful)
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So while you might not be talking about cellphone size, you'd still be talking about vastly shrinking the size of current projectors - a lot of whose size and weight is currently taken by optics.
Still...you're not going to see me buying one of these for a long time.
Tiny motors have "breaks easily" written all over them (although its too small to see).
Cheaper TVs? (Score:3, Insightful)
-uso.
Doesn't sound too good to me... (Score:3, Interesting)
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Why so many scan line mirrors? (Score:2, Insightful)
But more importantly was how to solve the Vertical scan issue?
Simple, A hexagonal mirrored surface (add more surfaces, get a higher refresh rate).
This way you only need the one horizontal high-speed scan, and a 'relatively' slow Vertical
Hello Virtual Boy (Score:4, Informative)
It looks like they've replaced LEDs with lasers and more of them.
I'm still waiting for cheap small (2" max in width/height) high resolution (640x480 min) LCD displays so we can finally hook up head mounted 3D displays to our next gen game consoles that have dual video out so you can hook one console up to two TVs for dual player action/wide screen action or to one pair of 3D glasses so we can view our 3D games in 3D.
Ignorant question time... (Score:2)
Wouldn't doing things by scanlines mean lower resolution overall without massive scanning capability to split lines into individual pixels? If not that, then would the power consumption made by such a theoretically small device not be great anyways in order to process this kind of information?
I only ask because I am curious, and I don't understand much about th
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Re:A Step Up (down in size) from this (Score:5, Interesting)
Parent
Re:A Step Up (down in size) from this (Score:5, Insightful)
we could get the scan rate higher. The optics just hum drawing those lines (laser video isn't vector scanned like most entertainment laser applications). The beam from a laser big enough to do outdoor video might be 1/16th of an inch or bigger before it even leaves the projector head. So even a mirror just 1/8th wide is needed to scan the beam. And that mirror has to move stop and redraw thousands of times a second. One mirror rotating for horizontal refresh, one galvonmeter for vertical drawing (this is the part that gets really sticky on a big screen) and an AOM for the color changes (a custom grown crystal that will vibrate at different frequencies when in the presence of an RF signal, thus blanking the beam (turning it off and on) and diffracting it (picking the color).
Also, if we could get the color right. Solid state lasers are helping here quite a bit, though the blue lines could still use more brightness. But until the big solid state lasers come down in price, a lot of the pros (and I don't mean the guy who did the lasers at your rave) are still dependent on their ancient SpectraPhyscics 171. Three phase power, a fire hydrant's worth of water, a drain, two men to carry the exciter, two to carry the head, two to carry the projector, and thats just one laser. Our small shows had three (one for full color graphics, two for beams in the air). Mosat guys are now using sold state yags for their beam effects. The solid state full colors are pricey. I believe the laser show at Hershey Park is using a full color solid state laser, I don't know who else, its been a few years.
That being said, laser video is starting to show up in more and more places, and it is looking really good. Just don't expect to be putting one in your living room any time soon. Aside from the cost, lasers are heavily regulated in the US. One bright enough to replace your tv is going to require a whole host of permits from the CDRH (Center for Devices and Radiological Health) and your state, plus don't even think about doing your own laser display outside, the FAA's paperwork will make your head spin.
PS, apologies to all the laser jocks if I got something horribly wrong, its been a few years for me, its late, I have a screaming infant and I'm doing this all off the top of my head.
Parent
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I'm not sure quite what you mean by a "full colour laser". You can have three colour laser beams - one in R, one G and one in B. However ideally for full colour representation you want 5 beams. This is because it's monochromatic and the eye's sensors o
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This might be a silly question, but why couldn't you just have the light from the horizontally-rotating mirror bounce off a vertically-rotating mirror, instead of a galvonometer-controlled one?
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Where exactly is it supposed to be?
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There's an expression in the audio industry: "No highs, no lows? Must be Bose." That said, the expression is a bit outdated. These days, they've pretty much gotten the highs.... :-)
In short, you're right. Smaller Bose speakers can't compare with a larger driver. The reason is that lower frequency sounds are less directional. This means that they have to be much louder to be header at any useful distance (which is why your headphones lose their bass response very quickly as you pull them away from yo
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A large cone attached to a driver is one way to get good impedance matching for delivery of a low frequency, but not the only one and not n
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Oh, that's easy by comparison. Use 1/4" thick piano strings at extremely low tension, and maybe raise the bridge a bit.... The problem is making it be as LOUD as a double bass. :-D
The bow would have to be light as a feather to avoid changing the pitch of the string radically at the tension involved, and because of the low tension and the light bow, you'd have to put pickups in the bridge and the player would have to play using headphones in order to hear any sound. :-)
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