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Does someone know why all these small laser mems projectors are discontinued? Anyview, Sony, ... Is it a reliability issue? I found them quite interesting for

Does someone know why all these small laser mems projectors are discontinued? Anyview, Sony, ... Is it a reliability issue? I found them quite interesting for similar applications especially as there is no need to focus and an image on a curved abject is possible.

kedikedi 3y ago
I have two of the microvision ones and I can tell you the reason: they have to scan to draw and that makes everything look very wobbly. It isn’t something you can clearly see but it is stil somehow visible (through peripheral vision I suppose). It makes looking at still images and text very tiring. Theoretically you can make it scan faster and that’ll fix it, but there’s probably more to it than just faster scanning.
- sllabres 3y ago
  Thank you. I've never seen them live, only videos and picture stills. Is the wobbly image a problem if you are 5 meter away from the projected image? As written i only know models not longer available: Nebra AnyBeam, Sony MP-CL1A, Celluon PicoPro, RIF6 Cube, My assumption was that they are all using the same MEMS unit and that this unit is not longer available for some reason. PS: If one is interested in a tear down of such unit: https://www.youtube.com/watch?v=RuNyQKvx9zc https://www.youtube.com/watch?v=RuNyQKvx9zc
  - kedikedi 3y ago
    One of mine is microvision, but the other one had a different brand (I don’t remember the brand though). But they are exactly the same machines except the text on them. The VGA accessory works perfectly with both. Regarding the image quality, both getting the screen closer (I.e. having a smaller screen) or going farther from it helped. What also helped was the location of text! It is better in top and bottom but worse in the center because of the unique way it works: the mirrors swing in a resonant fashion. So there are more horizontal scan lines towards the minima and maxima of the vertical scan sine. It is a really brilliant technology overall! Watching movies in the woods from distance, it was quite decent. The contrast is pretty good since black is actually black, very unlike lcd-based projectors. It didn’t have enough white for some scenes but we were watching dark horror stuff anyway :) I hope they could eventually make it scan faster or get better timing to overcome the downsides.
u_s_e_r 3y ago
I suspect there was a limit to how fast you can raster scan these and hence how many lines of resolution you can achieve. The next technological step with laser scanning was to move from straight lines to harmonic motion: your mirror has a resonant frequency and you vibrate one axis at a low frequency and the other at a much higher harmonic but now you need to draw your picture across a complex lissajous pattern with non uniform brightness, requiring a lot more dsp and timing precision I suppose. I was excited to see this progress but nothing commercial ever came of it. R&D was being done at Fraunhofer Institute. The other problem with these laser projectors is the bright “sparkle” pattern they produce.

kedikedi 3y ago

I have two of the microvision ones and I can tell you the reason: they have to scan to draw and that makes everything look very wobbly. It isn’t something you can clearly see but it is stil somehow visible (through peripheral vision I suppose). It makes looking at still images and text very tiring. Theoretically you can make it scan faster and that’ll fix it, but there’s probably more to it than just faster scanning.

sllabres 3y ago
Thank you. I've never seen them live, only videos and picture stills. Is the wobbly image a problem if you are 5 meter away from the projected image? As written i only know models not longer available: Nebra AnyBeam, Sony MP-CL1A, Celluon PicoPro, RIF6 Cube, My assumption was that they are all using the same MEMS unit and that this unit is not longer available for some reason. PS: If one is interested in a tear down of such unit: https://www.youtube.com/watch?v=RuNyQKvx9zc https://www.youtube.com/watch?v=RuNyQKvx9zc
- kedikedi 3y ago
  One of mine is microvision, but the other one had a different brand (I don’t remember the brand though). But they are exactly the same machines except the text on them. The VGA accessory works perfectly with both. Regarding the image quality, both getting the screen closer (I.e. having a smaller screen) or going farther from it helped. What also helped was the location of text! It is better in top and bottom but worse in the center because of the unique way it works: the mirrors swing in a resonant fashion. So there are more horizontal scan lines towards the minima and maxima of the vertical scan sine. It is a really brilliant technology overall! Watching movies in the woods from distance, it was quite decent. The contrast is pretty good since black is actually black, very unlike lcd-based projectors. It didn’t have enough white for some scenes but we were watching dark horror stuff anyway :) I hope they could eventually make it scan faster or get better timing to overcome the downsides.

u_s_e_r 3y ago

I suspect there was a limit to how fast you can raster scan these and hence how many lines of resolution you can achieve. The next technological step with laser scanning was to move from straight lines to harmonic motion: your mirror has a resonant frequency and you vibrate one axis at a low frequency and the other at a much higher harmonic but now you need to draw your picture across a complex lissajous pattern with non uniform brightness, requiring a lot more dsp and timing precision I suppose. I was excited to see this progress but nothing commercial ever came of it. R&D was being done at Fraunhofer Institute. The other problem with these laser projectors is the bright “sparkle” pattern they produce.