Laser Projector

[lanael]

A 848x480 pocket-size laser video-projector : that could be an interesting device for Pandoras !

http://www.microvision.com/showwx/index.html


EDIT : A french site wrote that this thing costs 350€. Don't know where they get the info. Also, it's not clear for me if it's yet available to customers ( the site explains that they target a march 2010 for the USA market ).



BTW, this is my first post here. I ordered my Pandora 6 months ago. Just say welcome !

 

[greendots]

Welcome!

 

[darien]

There's a lot of pico projectors coming out. I heard about one a long while ago that came attached to a video/picture camera in the works as well. Since Pandora is only composite out at the moment, that's probably the maximum you'd need. This one seems to come with a pretty hefty sized dock just to work with a regular laptop. Smaller for the iPod.

 

[kingoddball]

Looks great!
Did you see a price?
I found a few similar on ebay a while back.

 

[fischju2000]

"Composite adapter to other TV-out devices via a dedicated adapter cable"

"In The Box

...

Composite adapter"

Here is a video of that projector from CES 2009: http://www.youtube.com/watch?v=FOZdCoXjDrw and 2010's: http://www.youtube.com/watch?v=q0f_zKzK7ZY

The picture quality even in these bright showrooms looks very good, but 400 quid is about $650 USD.

 

[Pleng]

I was interested in purchasing a Pico Projector about 6 months back. It seems that the current generation have a lot of failings. They're apparently just not bright enough to use in anything but total darkness at the moment.

I don't know if that applies to this device as it's lazer based.

Anyway I'm keeping my eye on them. Could be a lot of fun one day!

 

[darien]

Hmm too bad about the price, I'm looking to buy two pico projectors and mod them into a 3D projector.

 

[Wolenber]

Wow, this actually really interests me, as I was planning on buying a projector soon anyways.

Does this device make any claims on battery? I would be willing to buy it if the battery was good and it could charge while using, but the website is not helpful in the least.

EDIT: Nevermind, I found the battery claims. Now what worries me is the "Brightness: 10 Lumens." Doesn't a lightbulb produce more than 500 lumens?

 

[Lafazar]

I've been following this device for some time. If I get a pico projector it will be this one. It would really be a perfect match for Pandora, since it matches Pandoras max video out resolution.



Advantages of Laser projection
-Picture is always in focus, even on curved surfaces
-Great color saturation
-More efficient use of light than LCD. (LCD technique always creates light, then blocks it wia LCD panel, even if the picture is black, Laser projector in contrast simply turns laser off)
-Of course this also means: Much better contrast than LCD
-No lenses or optics that can scratch, just a simple glass window

Disadvantages of Laser projection
-Speckle artifacts (hard to describe how they look, I also haven't seen how they look on a showwx and if they are even a problem)
-Laser/eye safety concerns make it necessary to keep the output power low. I'm not sure if we will ever see a laser projector that is brighter than this showwx, even though it would be awesome.
-Image is scanned, like on a good old CRT screen. You should only ever notice this when filming the projected image with a camera, though.



Battery runtime is said to be 1.5-2 hours, depending on the type of content (see advantages below, in short: dark videos use less power). And: You can power it over USB.

Keep in mind that this is a projector that fits in your pocket. It is really not that bright and only usable in low light conditions if you want a really large image. However, you can simply decrease image size (that means getting closer to the surface you are projecting onto) until the image is bright enough for you.



Here's some information and videos about possible uses of this thing:

A microvision employee playing around with a prototype. He has some pretty cool ideas, playing around in a city at night (note: I am not quite sure if his prototype has more light output power than the final consumer model):

http://www.youtube.com/user/picounderground

Combine a pico projector and a gun controller and you get an awesome new way to play first person shooters:

http://www.engadget.com/2009/12/11/microvisions-picop-laser-projector-meets-rifle-shaped-motion-co/
http://www.crunchgear.com/2010/01/10/hands-on-with-microvisions-pico-projector-equipped-gun-controller/

Company blog:
http://www.microvision.com/displayground/
Unofficial blog:
http://www.mvisbuzz.com/

This whitepaper explains very well how it works:
http://www.microvision.com/pdfs/Scanned%20Laser%20Pico%20Projectors.pdf

Hmm too bad about the price, I'm looking to buy two pico projectors and mod them into a 3D projector.

I was thinking about doing this myself. How were you going do it? With a laser projector it should be really easy, provided it puts out linearly polarized light.

I expect the prices of laser projectors to fall dramatically once they get a larger exposure, since the components are not expensive when produced in quantities.

 

[Wolenber]

Man, I don't have a clue on anything to call that, except maybe for "Awesome."

 

[paulguy]

Sounds neat, unfortunate about the various laser laws in different countries, though... perhaps someone can mod it to increase the output, and have a big fat battery to go along with it.

 

[darien]

I was thinking about doing this myself. How were you going do it? With a laser projector it should be really easy, provided it puts out linearly polarized light.

My plan was to experiment by breaking 3D glasses and projecting 2 pictures through each eye and then seeing if it acts as a polarizing filter for the light. Then basically wear another pair of glasses and see them in 3D. If not I can just buy the lens, but it's cheaper to use free theatre glasses hahaha.

 

[darien]

My plan was to experiment by breaking 3D glasses and projecting 2 pictures through each eye and then seeing if it acts as a polarizing filter for the light. Then basically wear another pair of glasses and see them in 3D. If not I can just buy the lens, but it's cheaper to use free theatre glasses hahaha.

You know I just tested this on my current projector and it does not work, so I will just have to buy the actual lens that does it.

edit: actually I'm seeing something sort of work, I might just need more filters to fully block out one image or rotate the lens filter more.

 

[Lafazar]

I was thinking about doing this myself. How were you going do it? With a laser projector it should be really easy, provided it puts out linearly polarized light.

My plan was to experiment by breaking 3D glasses and projecting 2 pictures through each eye and then seeing if it acts as a polarizing filter for the light. Then basically wear another pair of glasses and see them in 3D. If not I can just buy the lens, but it's cheaper to use free theatre glasses hahaha.

Yes, that would actually work. I did a rough analysis on those "RealD Cinema" glasses and they seem to consist of a linear polarizer followed by a lambda/4 plate to convert linearly polarized light to circularly polarized light and vice versa. So the direction that the light passes through the glasses is important!

In theory, what you would need to do is put the glasses in front of the projector with the side that points to your eyes towards the projector and then you should be able to see the projected image with only one eye when wearing a second pair of glasses.

Unfortunately that is usually not enough. You need a special screen to project onto that scatters the light in a way so that it keeps its (circular) polarization properties. You can test various surfaces without buying a projector, just beam a simple flashlight through one side of the glasses and see if you see the flashlight beam projected onto a surface only through one eye when wearing the glasses. The better the beam is blocked for the other eye, the better that surface will be for 3D projection.

http://en.wikipedia.org/wiki/Real_D_Cinema#Technology

You will lose a lot of light using those cheap glasses, though. A much better solution is buying a good linear polarizer and a quarter wave plate that works at all the wavelengths your projector puts out (!).

http://www.newport.com/Polarization-Optics/141144/1033/catalog.aspx
http://www.edmundoptics.com/onlinecatalog/browse.cfm?categoryid=166
http://www.thorlabs.com/navigation.cfm?Guide_ID=8

The great advantage of laser projectors is (or so I hope, I wasn't able to test it yet) that the light coming out is already strongly linearly polarized, so all you would need are two lambda/4 plates to make a 3D projector that works with the cheap "RealD Cinema" glasses.

 

[darien]

You know at those prices, it seems to make more sense just to buy stereo video glasses ahaha :lol:

 

[Lafazar]

You know at those prices, it seems to make more sense just to buy stereo video glasses ahaha :lol:

Yeah, wave plates are expensive. And then you still need a suitable screen.

A much cheaper alternative would be using two laser projectors that put out slightly shifted colors. Since lasers emit a very narrow wavelength spectrum, there is no overlap even at small shifts.

Then a simple color filter for each eye could block one of the images.

 

[elwing]

A much cheaper alternative would be using two laser projectors that put out slightly shifted colors. Since lasers emit a very narrow wavelength spectrum, there is no overlap even at small shifts.

Then a simple color filter for each eye could block one of the images.

A similar product exist (and it's maybe patented?)

 

[pelrun]

Disadvantages of Laser projection
-Speckle artifacts (hard to describe how they look, I also haven't seen how they look on a showwx and if they are even a problem)

Probably not an issue; the scanning should blur out the interference patterns that cause it.

-Laser/eye safety concerns make it necessary to keep the output power low. I'm not sure if we will ever see a laser projector that is brighter than this showwx, even though it would be awesome.

Why? There's nothing magically dangerous about a projected laser image compared to a standard projection. Lasers just happen to be really efficient at cramming their energy into a small area - when it's spread out using scanning or optics then that issue vanishes. You just don't want to look directly into *any* bright projector, regardless of whether it's LCD, DLP or laser.

-Laser diodes are slightly less efficient than common LED when converting electric current to light.

But it's already far *more* efficient than the equivalent LCD setup, and hence runs far cooler. Green lasers are only inefficient compared to other lasers.

You need a special screen to project onto that scatters the light in a way so that it keeps its (circular) polarization properties.

You can buy a silvered projection screen, or you can paint a wall/board with 'aluminium'/metallic paint, which seems to also do the trick. As do metallic poster board sheets, I'm told.

 

[Asmo]

I've been following this device for some time. If I get a pico projector it will be this one. It would really be a perfect match for Pandora, since it matches Pandoras max video out resolution.

The Pandora's video output is S-Video or Composite though, you cannot get actual 800x480 output to match the projector's native resolution - furthermore, you will be up against whatever capabilities the device has for handling those kinds of analogue signals, quality can vary widely.

 

[Lafazar]

A similar product exist (and it's maybe patented?)

Yeah, I know. Just talking about cheap DIY possibilities here.

Probably not an issue; the scanning should blur out the interference patterns that cause it.

Yeah, that's very probably true. I haven't seen a Showwx in action yet, so I cannot judge it personally. This person has, though:

Regarding the speckle. Hearing about it over the years made me cautious. And I came to find that it didn't really bother me that much. However I was surprised that I could detect what the scanned lines. And I wondered if actually people were confusing that with speckle. I don't know. It did bug a bit, but it's more noticeable on still images and for videos it's much less noticeable. I also found that with speckle or the scan lines, that if you just relaxed or if you didn't go looking for it, your eyes could come to ignore it. It could also be a personal thing.

http://www.mvisbuzz.com/2010/01/back-from-ces-2010.html

Why? There's nothing magically dangerous about a projected laser image compared to a standard projection. Lasers just happen to be really efficient at cramming their energy into a small area - when it's spread out using scanning or optics then that issue vanishes. You just don't want to look directly into *any* bright projector, regardless of whether it's LCD, DLP or laser.

You know that and I know that. The problem is that raising the laser power above 1mW will automatically make the projector a Class 3 (above 5 mW even Class 3B) laser product which is illegal to own in some countries for private persons (it's considered a weapon in Germany, for example). USA will confiscate parcels containing class 3 laser products if they find them at customs, etc. etc.

Unfortunately laser classes only consider total output power and not the illuminated area.

It's just a huge pain in the ass selling and distributing such a product, so I guess they will shy away from that.

But it's already far *more* efficient than the equivalent LCD setup, and hence runs far cooler. Green lasers are only inefficient compared to other lasers.

True, I should remove that point.

You can buy a silvered projection screen, or you can paint a wall/board with 'aluminium'/metallic paint, which seems to also do the trick. As do metallic poster board sheets, I'm told.

Thanks for the info, I didn't look into this yet.

The Pandora's video output is S-Video or Composite though, you cannot get actual 800x480 output to match the projector's native resolution - furthermore, you will be up against whatever capabilities the device has for handling those kinds of analogue signals, quality can vary widely.

If I remember correctly there is no real standard on the number of "pixels" per line in these analog signals, just the number of lines is fixed. As far as I know it's possible to transmit a great variety of "pixels" per line, even exceeding the standard number of pixels for a standard 4:3 image, the receiver can then just sample the analog signal x times each line.

But yeah, it all depends on what the Showwx can handle.

Edit: I just found something, the people at microvision have already done a 3D demo:

And I was surprised to see the 3d demo. The demo consisted of two side-by-side SHOW WX's, a filter, a special screen and of course the glasses. This was an ability that I was not aware of, and it was pretty cool. I asked about the technology and it is made possible because it uses lasers(frickin') and their inherent, polarized light property. The filter and screen are available on the market for a couple hundred dollars. The software which does the rendering is free online, and it sounded to me like anyone with two SHOW WX's should be able to set it up fairly easily. Given what I said about the PicoP being best for mobile projection, I'm not sure if people would want to use it in a fixed manner like this, but it did demonstrates a unique ability and it was pretty sweet trick.

http://www.mvisbuzz.com/2010/01/back-from-ces-2010-2.html

It would be really cool if there was some way to output two separate video signals from Pandora, perhaps abuse interlacing and some cheap electronics to split the signal?