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Video Projector on a Chip?
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."
Finally, the resolution of a cellphone VDU on a screen the size of a bedsheet! Amazing!
Agreed! Although Light Blue Optics Ltd's devices aren't available on the market yet, and they claim to have no mirrors, prisms, or moving parts. I poked around in Feb when LBO announced their laser projector tech. I couldn't believe no one had tried to make a cheap laser/mirror scanning projector. I found some patents on the technology from the 70's that appear to be used by companies doing the "Pink Floyd laser light show" type devices. They just don't understand what they have could be used to kill off the multi-million dollar LCD projector market, home theater, and even win the LCD/Plasma/OLED/etc TV wars.
Virus that causes porn movies to randomly play through this display on cell phones. Man that would be embarrassing in a public place like a mall or something. Which is exactly why someone is going to make it.
The largest silicon chips approach a billion devices at a cost of $0.0001 cent per device. What is the manufacturing efficiency of carbon fibre?
What does this have? Phosphors hold their brightness a little bit, down a reducing curve. This sort of display would have the scan line refresh issue of CRTs without the benefit of the fade curve, the light disappears immediately, so then it's just retina response time. I would expect that this would have to have a pretty high refresh rate to not be annoying. Will this allow three-chip operation? Consumer DLPs have a "rainbow effect" because only one chip flashes out the red, green and blue parts of the image. This doesn't bother everyone but I suspect that this system will have similar laments.
No, its not such a new and great idea. Schneider was building a project "laser tv" 15 years ago.
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).
HI O WISE PRINCE. WHT TOOK U SO DAM LONG?
"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 is just what we need. There's already people on the subway that use the speaker on their phone to subject everyone to their poor taste in music. Now we'll have people subjecting everyone to their poor taste in television as well.
The theory of relativity doesn't work right in Arkansas.
*phone rings*
*display activates*
Princess Leia: Help me Obi-Wan Kenobi, you're my only hope!
I keep telling myself I'm not the desperate type.
so, in 5 years will princess leia send me a video message?
give a power point presentation to the other people on the bus!
The Kruger Dunning explains most post on
Since it uses one fibre per scane line the oscillation rate is the same as the refresh rate.
Yes you need a lot of power, but you do not need all that power in a single coherent beam.
Since the image has a fibre per scanline you can use lots of low power laser diodes.
what kind of cell phone is going to have the power to do video projection
One powered by a Dell laptop battery.
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"Help me Kemo_by_the_kilo, you're my only hope......I am the princess of an aquabarian abbassador who was killed in..."
or
"Help me Kemo_by_the_kilo, you're my only hope is what your woman will say with your new prehensile penis!"
The Kruger Dunning explains most post on
You still need a light source -- in this case, lasers. Yes, I know you can get red lasers dirt cheap, but any thing else is very expensive. A laser light source operates at a defined wavelength, and although you cannot easily generate the full spectrum of colors from a single laser. You can get a red, green, and blue laser to potentially mix to generate the full visible spectrum, but the green and especially the blue lasers are very expensive. Also, size does matter -- it is difficult to pack bright light power sources into a small space, like say a cell phone. The techology leap forward here is great in principle, but the phrase "Video projector on a chip" is incorrect, since only the mirrors are on the chip, not the light source.
I'd like to see if a regular, broadcast TV could be designed to use one of these and project on my wall, and how well it would rival current home theater setup.
-uso.
What you hear in the ear, preach from the rooftop Matthew 10.27b
GreyPoopon
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Why is it I can write insightful comments but can't come up with a clever signature?
About the same as a common laser pointer 5mW is a lot of laser light at least in red, not sure how much more you'd need for a decent green or blue laser so let's guestimate 25mW total for indoor usage, a 1/2 W would probably handle outdoors in almost direct daylight I'd guess. These figures are very reason considering what a plasma display or a LCD projector would consume.
Apocalypse Cancelled, Sorry, No Ticket Refunds
I was thinking about a project like this when I was a wee little kid. Back then I though that you could send the scan thru an oscillating crystal, but it never would have worked out. Oh and the fact that a blue laser (or full color?) was in the 10's of thousands of dollars.
:)
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 scan.
Apply it to movie theaters... up the wattage of the lasers used and the number of surfaces on the vertical drum. Take that IMAX!
Well, I'm sure it will never happen. but when I was 16, boy could I dream
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.
Well, they're talking about two things, they probably mean that the modulus of elsticity (the "stiffness", based on Young's Modulus, expressed in psi or pascals) is double that of silicon, but the yield point, or flexibility (how far it can bend before it permanently deforms) is 10 times that of silicon. It's a dumbing down of the mechanical properties using common language and, no, it really doesn't make sense the way they've presented it if you try and apply logic to the langugae they've used.
Is it just my observation, or are there way too many stupid people in the world?
Green would actually need to be a lot less power, since your eyes are much more sensitive to green than anything else. A 5mW green YAG looks a hell of a lot brighter than a 5mW red diode, for instance. Similarly, you're less sensitive to blue, so the blue component would have to be ramped up to compensate. I've yet to see any low-cost solid-state blue units yet, though.
Please stand clear of the doors, por favor mantenganse alejado de las puertas
The Virtual Boy had a single column of LEDs and a vibrating mirror for each eye.
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.
Work Safe Porn
"Volume of air moved" is the wrong way to think about speakers (because its a meaningless construction in terms of physics). The correct way is in terms of impedance matching, i.e. efficiency of power transfer across the spectrum between the driver and the medium (e.g., open air, an ear (circumaural headphones), an ear canal (insert headphones), water (hydrophone), etc)
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 necessarily the best since it has some drawbacks (mass, flexibility, fragility, etc). Even so, its often not that good, and a lot of speakers end up being absurdly overpowered because they are so inefficient. Its like having a sports car with bald tires... pointless.
Another way to do impedance matching is with an exponentially tapered waveguide, i.e. a horn. e.g. a brass instrument or an old acoustic record player. I don't vouch for the quality of Bose products, but the Bose "Wave" product essentially contains a long waveguide hidden in the box.
Other tricks include stuff like bass porting and resonant cabinets, and on most speakers you will see some combination of all the above.
Seriously, those folks need to get this out. There is nothing I would enjoy more than being able to watch a podcast of 24 on the bathroom wall / stall door whilst exercising the large veins in my forehead over last night's chili.
The applications are endless:
-projecting "kick me" signs on your buddy's back
-literally labeling people in bars as you approach them (your typical loser, desperate single guy, lush, the "come on, we're going" girl, designated driver, career drinker, future mayor of the drunk tank, the "you think that's bad, I..." guy, will puke, have puked, laughed so hard I peed a little, kinky, not really a girl, high maintenance, "forgot" my wedding ring, etc...
-projecting the definition of a 6-pack on my gut (among other body mods to various people...)
-showing movies on your wife's forhead so it appears that you are paying attention to her when she is saying...whatever it is that she says.
I'm in - let me know when it's selling for 1/2 price on ebay at 2am. I've got cable internet and I'm not afraid to wait until the last 3 seconds...punks.