Re: Starting at the beginning with Mirror Screws
Posted: Fri Aug 28, 2020 10:01 pm
I am now have a little time and am intending to take this forward: convert my Mirror Screw to project a 'real' 120-line colour picture onto a screen. It 'sucks' having to watch a virtual/reflected picture from across the room!
I think... a vertical line of laser light would give linear results shone at the centre/axis. This could be produced by shining a laser through an acrylic rod (cylindrical section).
I also think... a converging vertical fan of light from LEDs and rod (focused further on, on a screen) would do the same, but with possible vignetting at the line edges.
I could be wrong.
Karen's Slat Angle Timing Corrector and RGB Converger would be as useful as ever. A screen would capture just the corrected edition of the picture.
The screw is 180mm tall. So a 4:3 picture would be 240 mm wide. I therefore reckon a correctly proportioned '12-inch' diagonal picture should be available
about 7½ ft from the screw.
I am looking into using R G and B laser diodes, such as THIS. These devices are extremely eye-unsafe. I welcome all warnings. Maybe stretching the beam into a line-ended fan will mitigate? Maybe they could be under-run by the modulator circuit? I value my eyesight and the eyesight of others even more, to the extent that, unless adequate safety protections can be built in, this may put the stopper to the whole project. Are ready-made laser modulators available these days? I'm back to being new to all this, having just got back in the saddle.
I think I may start by getting a ready-made "collimating+line" laser lens and see if this can be made to work with a narrow-angle LED...
Thanks for reading. Your advice is valued.
Steve O
I think... a vertical line of laser light would give linear results shone at the centre/axis. This could be produced by shining a laser through an acrylic rod (cylindrical section).
I also think... a converging vertical fan of light from LEDs and rod (focused further on, on a screen) would do the same, but with possible vignetting at the line edges.
I could be wrong.
Karen's Slat Angle Timing Corrector and RGB Converger would be as useful as ever. A screen would capture just the corrected edition of the picture.
The screw is 180mm tall. So a 4:3 picture would be 240 mm wide. I therefore reckon a correctly proportioned '12-inch' diagonal picture should be available
about 7½ ft from the screw.
I am looking into using R G and B laser diodes, such as THIS. These devices are extremely eye-unsafe. I welcome all warnings. Maybe stretching the beam into a line-ended fan will mitigate? Maybe they could be under-run by the modulator circuit? I value my eyesight and the eyesight of others even more, to the extent that, unless adequate safety protections can be built in, this may put the stopper to the whole project. Are ready-made laser modulators available these days? I'm back to being new to all this, having just got back in the saddle.
I think I may start by getting a ready-made "collimating+line" laser lens and see if this can be made to work with a narrow-angle LED...
Thanks for reading. Your advice is valued.
Steve O