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Very small holographic laser projectors and diffraction.

  1. Sep 28, 2014 #1
    In thinking about what it would take to make a feasible invisibility cloak or holographic disguise or perfect hologram room, I've imagined something that works like this:

    A light beam "image" is projected onto a device designed to refract or reflect it in all directions, but only 1 color in any given direction. A camera is also built in using the same lens and the camera also reaches diffraction-limited performance levels.

    The problem I'm imagining, is that if the pupil or telescope or whatever that I'm trying to hide from or fool or entertain with ultra-realistic 3D images is larger than the reflector or lens size, the beam will not be diffraction-limited and thus will look like a person-shaped or plane-shaped or tank-shaped blur from, say, a sniper scope or spy satellite or someone with good eyes.

    On the other hand, if the cells are too big, the fact that some of the light is coming from the wrong angle and being simplified into pixels and such becomes clear.

    My question is:

    Is there any way to correct this or mitigate it? Would large projector cells actually work fine and look perfect to smaller pupils and not be suspicious and I'm just being paranoid? Is there another issue (besides things like how expensive it would be to merge a camera with a laser projector and have both of them be at nearly diffraction-limited performance and completely coat a large object in them and power it somehow)
  2. jcsd
  3. Oct 3, 2014 #2
    Thanks for the post! Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
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