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Matchbox-sized Laser Projector
soupisgoodfood writes "Light Blue Optics Ltd. have developed a laser-based projector called the PVPro. It's small enough to fit into a cellphone or PDA.
Some specs: Supports resolutions up to 2048x1280; No moving parts; Infinite focus; Green monochrome, with a colour version expected late 2006; Max consumption of 1.4W with an average of <350mW.
Looks a like a good solution to the increasing problem of smaller devices trying to display more information."
The Fraunhofer Institute for Photonic Microsystems in Dresden, Germany actually had a similar Projector one year ago.
It works at 640x480 in Full Color (3*8 bit).
It's even smaller at the size of "2 sugar cubes".
See here for yourself
From the PDF:
Typical Diagonal Image & Brightness: 7" @ 800 cd/m^2 - 15" @ 200cd/m^2 (50% max average pixel amplitude)
What good is all that resolution when you can't get the viewing area above 15" without going to a dark room?
Not that it's not a brilliant (hah!) achievement, anyway. Bring on the fanless projectors!
That's actually a 2p coin, it's about 2.5cm in diameter.
I am one of many. My idea is not unique, nor do I expect my voice alone to sway you. I speak in a chorus of opinion.
Mecury arc lamps have much _lower_ profit margins then other consumer electronic parts. So do projectors in general. The lamps have very exotic materials in them, like very very pure tungsten and specially manufactured quartz casings. You're not getting ripped off. The prices would come down some if more projectors were out there in people's living rooms, but not by much. If there were really a racket on mecury arc lamps, we could do something about it. Hopefully laser tech will eliminate the need for these expensive ( and very polluting, in manufacture and waste ) mecury arc lamps.
That won't work: There's no red light in the blue-violet laser. Indeed, the laser has just one exact wavelength, so a filter could not change its color (because the color change is done by absorbing different wavelengths). The "problem" is within our eyes, because our red-receptors don't just react to "red light" (longest visible waves), but also to "blue-violet light" (shortest visible waves). So unless you find a way to create "negative red" (i.e. a sort of light which suppresses the red receptors instead of activating them), there's no way to supress that "red".
The Tao of math: The numbers you can count are not the real numbers.
Moreover, years have gone by already since Schneider/Jenoptik demonstrated their "laser display technology" (albeit "diode-pumped solid-state", i.e. not quite as tiny...) and announced to have "developed the heart of this technology, the Red-Green-Blue laser (RGB laser), ready for mass production." [sic!]
After poking around on the site, I found a link to a press release containing a PowerPoint (yuck!) presentation. There were some images in there, which I've posted to my company's technology blog.
The lasers in Blu-Ray players will likely be very small, very precise devices that would not translate directly into a laser projector system like this.
- It's not the Macs I hate. It's Digg users. -
It's called "laser speckle". It shows up when a coherent beam is held fairly stationary on an irregular surface. I imagine that if the beam is scanning fast, it won't be much of a problem because the specks will be too brief for your eye to see. POV will take care of the problem. But, of course, I haven't actually tried this myself.
Use this to project a fake doorway onto walls and watch your victims slam into walls, ala Bugs Bunny.
Bugs Bunny cartoons do not feature advanced technology whereas Roadrunner cartoons do. So what really would happen is that you would project a fake doorway onto the wall, your intended victim would walk up to the wall, open the door, walk through the doorway and close the door behind. Astounded, you'd run to the door only to slam into the brick wall, a la Wile E. Coyote.
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You didn't read the spec sheet. The brightness at 15" is 200 candela - aproximately the brightness of a LCD screen. The brightness at 7" - half the distance - is 880 candela. Now do a curvefit and tell me how bright it is going to be at a comfortable viewing distance - 120"++ for a home theater (~50 candela). (answer: not very.)
That makes sense to me if there are 2048x1280 laser sources, i.e., one for each pixel.
No need. Think about how a CRT works. You aim the laser at each of those pixels for a fraction of a second, scanning the entire surface, and repeat fast enough for it to look to your eye like all the pixels are lit at once. In theory... But then there's more to it, which brings us to:
how do you get around the diffraction problem where the light from one pixel gets spread out over the other pixels?
From their release, it sounds like they have some dynamic "holographic" film that allows the beam, which is larger than a single pixel, to be filtered such that it displays multiple pixels within the beam, all while remaining cohesive. Think like the little lenses that they have to cover the ends of cheapy laser pointers, but can be changed on the fly with electronics.
Even a nice, collimated laser beam gives you a narrow waist only in a certain region, then spreads out from there.
That's why you have to put "infinite" in quotes. It would be infinite in a vacuum, in real life in an atmosphere it will actually only be in focus from zero to the point where diffusion due to the medium the beam is passing through becomes too great. It's still infinite in that there are an infinite number of distances within the finite range, but it's not infinite in that it'll still be in focus some rediculous distance away from the projector.