Meant to be Seen

Anyone know/heard/seen more about this: ST pico projector?

Seems it'll be a real product in some way or another: ST data

Believe pico projectors like this are a better way forward (eventually, cost/availability dictates things for now of course) vs. LCDs.

If you can integrate them easy and can get them for cheap, it would be a great alternative for sure. Especially the laser pico projectors because they have no latency and perfect black levels like Oled. I've owned a 480p Microvision laser pico projector in the past, and i think even John Carmack messed around with one too. Now it seems that they have a 720p model for OEM's only. The downside is most likely the price if you get two of them, probably more than 300$ each.

http://www.microvision.com/

I had a idea of mounting the projector on a helmet, backprojecting at a tiny screen on the helmet too, and having a concave mirror (actually a shaving mirror) in front of the eyes which would act as collimated display, receiving the mirror image of the tiny screen giving you a natural 3d effect. But after the Oculus went to Kickstarter i haven't worked on the ideas anymore and instead went more towards content production and programming.

I also thought about using a laser projector.
It seems to have some interesting advantages, like:
- good picture quality
- low weight (and weight closer to the head)
- fast (no blur?)
But there may be some disadvantages:
- cost
- speckle
- sequential image construction
- resolution

About cost: I suspect that in large quantities the cost of these devices will be ok.

About resolution: There are 720p versions now and this will be per eye when using 2 of them.
There is also the possibility to use more units per eye. More complex and more expensive but very interesting.

About Speckle: Is this a no go issue?

About sequential image construction: The image is build using colored laser beams and one or two rotating mirrors.
The image is build up line by line like the old CRT televisions. Will this be a problem for motion?
Will this lead to unwanted tearing or other motion artifacts?

What do you guys think about these disadvantages? Are there other disadvantages?

Steve, the laser projector does not result in perfect black levels. While it does not put light in the black areas, the stuff in the vininity of the projection surface will reflect light from the screen back onto the screen, and thus light up the areas intended to be black. Of course, adding black cloth to the interior helps, but some areas, like the lenses cannot be covered.

The speckle issue is resolved by some laser projectors by using a vibrating mirror, or perhaps other technologies. That would be an important thing to check out in person before purchasing.

You describe using two projectors. I imagine you are assuming they are polarized, and each eye is looking at the same screen through its own polarized filter. However, lasers are not necessarily automatically polarized in a consistent direction. So this might be an issue. The manufacturer, even if the laser is polarized, may not necessarily install the laser oriented in a consistent manner. This is another item to check in-depth before you purchase a laser projector.

Joe Dunfee

cadcoke5 wrote:Steve, the laser projector does not result in perfect black levels. While it does not put light in the black areas, the stuff in the vininity of the projection surface will reflect light from the screen back onto the screen, and thus light up the areas intended to be black. Of course, adding black cloth to the interior helps, but some areas, like the lenses cannot be covered.

The speckle issue is resolved by some laser projectors by using a vibrating mirror, or perhaps other technologies. That would be an important thing to check out in person before purchasing.

You describe using two projectors. I imagine you are assuming they are polarized, and each eye is looking at the same screen through its own polarized filter. However, lasers are not necessarily automatically polarized in a consistent direction. So this might be an issue. The manufacturer, even if the laser is polarized, may not necessarily install the laser oriented in a consistent manner. This is another item to check in-depth before you purchase a laser projector.

Joe Dunfee

In my laser projectors the color laser diodes are not all polarized in the same orientation (but fairly close), so polarized glasses cannot completely block all three colors at the same time, and compromising at an intermediate position lets a lot of the wrong 3D channel bleed through. Because they are relatively close though, if the laser diode leads are long enough, perhaps they could be rotated a little to get then into alignment. I also tried circular polarized lenses over the projectors, but they seem to have some degree of linear polarization as well OR the lasers also have circular polarization, so it is sensitive to orientation of the circular polarizing filters (passive 3D glasses) as well.

And yes, the aluminized "silver screen" needed for polarized 3D does become an issue as well. My silver screen has dog nose prints and child hand prints near the bottom that seem to be permanent...