Laser Projector

[pelrun]

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.

Hmm. Obviously, it depends on the exact laws involved, but a lot of these laws are directly targeted at laser pointers - lasers which are integrated into other devices don't endure the same scrutiny (hence you still being able to buy laser printers, blu-ray drives, etc.) A projector isn't really something which can be shined at a plane... well, I guess you could, but it'd be about as dangerous as a torch.

 

[Lafazar]

Hmm. Obviously, it depends on the exact laws involved, but a lot of these laws are directly targeted at laser pointers - lasers which are integrated into other devices don't endure the same scrutiny (hence you still being able to buy laser printers, blu-ray drives, etc.) A projector isn't really something which can be shined at a plane... well, I guess you could, but it'd be about as dangerous as a torch.

Yes, but most of these devices never expose the laser to the naked human eye, therefore they are rated as a lower class, even if the laser itself is rated at a much higher class.

Also, it just takes a simple mod (or accidental damage) to have the Showwx projector always point its beam in the same direction (just cut the connection to the controls of the MEMS mirror), and then it could actually become dangerous to a human eye if it had more than 1mW.

Well, I think we will just have to wait and see whether laser projectors will find enough acceptance and demand. If they do, the producers may well be motivated enough to overcome the safety and legal problems and make stronger laser projectors.

This would make really cheap and reliable home theater projectors possible (no more replacing expensive bulbs).

 

[Gilrad]

I wonder how feasible it is to hack into the projector's innards and overdrive the laser output? I don't know much about lasers but if the laser is able to handle higher power levels it should be a simple electrician's solder hack; no messing with chips or software.

Also I would imagine that any concern about scanning or speckles are probably linked to the distance viewed. Taking an educated guess on how we would perceive them in flesh-and-blood, I think that speckle would become more visible in short viewing distances, and scanning more visible at greater distances.

 

[Lafazar]

I wonder how feasible it is to hack into the projector's innards and overdrive the laser output? I don't know much about lasers but if the laser is able to handle higher power levels it should be a simple electrician's solder hack; no messing with chips or software.

I think that would be very hard, because the laser diodes are not continually on all the time, they are turned on and off depending on the brightness of each single pixel. They also produce more (too much?) heat and their lifetime is reduced when overvolted above specifications.

But if it's at all possible we will see the first mods pretty soon after release.

Also I would imagine that any concern about scanning or speckles are probably linked to the distance viewed. Taking an educated guess on how we would perceive them in flesh-and-blood, I think that speckle would become more visible in short viewing distances, and scanning more visible at greater distances.

The funny thing about speckles is that they are roughly the same size regardless of spot size and distance to viewer. They behave really contraintuitive. I can even see them sharply without glasses (when everything else is a blurry blob to me).

As for the scanning, that's another neat thing that's only possible with lasers: They made it so that the beam diameter is proportional to the distance, meaning the spot or "pixel" always takes the same fraction of the whole picture (that's also why the image is always in focus).

This makes me think the scanning effect should always be the same, regardless of distance/image size.

http://www.microvision.com/pdfs/Scanned%20Laser%20Pico%20Projectors.pdf

 

[fischju2000]

Engadget does a hands-on http://www.engadget.com/2010/01/11/microvision-laser-projection-gun-hands-on/