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Sony Projector Gets Bright Images From Black Screen
da_foz writes "Sony has developed a new projector that can give a bright, unfaded picture without the need to eliminate ambient light. The secret is that they project onto a black screen instead of a white one. Their screen uses species filters so that white ambient light is absorbed, but the red, green, and blue light from the projector is reflected. Sony sees a possible use in home entertainment systems because of the ability to have a much bigger picture than conventional TVs as well as businesses adopting the projectors for presentations."
This isn't a new projector. It's a new type of screen that only reflects the projector light, absorbing the ambient light, so the image remains clear even in a bright room. It works with regular projectors. I'd at least expect the submitter to RTFA...
Igor Presnyakov stole my hat
The author of the article doesn't know what he's talking about!
In a bright room, the image on the screen is brighter
No, it isn't. It's clearer, it might _appear_ brighter because of that, but there's no way it could actually _be_ brighter. Unless the technology does something not described.
Since Thomas Edison introduced motion-picture projectors more than 100 years ago
I could have sworn the motion picture projector was introduced by Lumiere.
The common vernacular "bright" can either refer to luminance (close the shades, the light's too bright), or it can refer to color saturation (Can you tone down that bright green to a mere pastel?). A projector screen that reflects ambient light is going to reduce color saturation; and one that absorbs ambient light will increase color saturation, i.e. make it brighter.
I've gone through at least 6 InFocus projectors in the last 1.5 years due mainly to bulb failure.
while I have the same bulb from 2 years ago still burning bright.
it's your use of your bulb and projector.
first off, buy a UPS for your projector and put it on there... only the projector goes on this ups. you want to be sure that your voltages are rock solid and no brownouts get to the bulb. Finally you are making sure that the projector is cool and is allowed a proper warm up and cool down before and after use?
proper care and operation of your projector lengthens bulb life significantly. if you are leaving the house for an hour then LEAVE THE PROJECTOR ON.. I would not shut off the projector unless I was going to have it off for more than 2 hours.
Do not look at laser with remaining good eye.
completely skirting around the fact that THERE IS NO SUCH THING AS WHITE LIGHT!
Sure there is, there's no such thing as white monochromatic light, but white light exists. The term "white" (whether it be talking about light, sound, etc.) simply means that the energy is distributed evenly across all frequencies (technically between 0Hz and infinity, but in practice we're talking about more or less evenly over a given band of frequencies). Since the energy is distributed over such a wide frequency band, the energy of the white light in the very fine bands used by projectors will be very small, so by absorbing everything else you will almost be eliminating the white light's energy.
Trueth be told, unless you're talking about monochromatic light, the simplistic names of colours only describe what we see - they can be generated by any number of combinations of different frequencies. I.e. monochromatic orange light has a wavelength of 590nm, but that would look the same to us as a mixture of red (650nm) and yellow (570nm) light (or any number of combinations of different wavelengths).
http://blog.nexusuk.org
The technology here is in the screen, not the projector. In particular, the screen absorbs most light, with the exception of the primary bands illuminated by the projector's bulb.
Any projector with the same type of bulb---and in home theater nowadays, there are only two main types (Xenon and UHP), will work with this setup. And Sony could conceivably make a similar screen for the other bulb type too.
There have been so many dupe threads over at AVS Forum (by far the best place to go to discuss anything home theater) that it is getting a bit irritating.
Reading the article (although it is a little shy on detail) suggests it is bandpass filters in addition to what you suggest. I'm not sure why you think you need more than R, G, and B to produce all the colors present in RGB video. To reproduce the entire visible color gamut, you'd need more than RGB-- but RGB video has already reduced the color gamut significantly from what you can see. And, conveniently, consists of exactly three narrow wavelengths of light, and nothing else. Your suggestion that images require "many wavelengths of light" is completely incorrect. You'll have issues if your only source of ambient light is a bank of computer monitors, though, as they'll fall right into that nice RGB range.
I'm not sure they'd put too much dependence on angle, either-- most projectors these days are designed with an enormous optical offset (The popular Sanyo Z2 can be offset by 1/2 screen width and 1.5 screen height) and digital keystone correction (Allowing for projector placement even farther outside the offset range by correcting the shape of a picture projected at an angle). Lots of people use projectors but don't have a room situated so that the unit can hang conveniently from the ceiling dead center.