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jb55 | 4 months ago (raw) | root | parent | reply | flag +2 
 My original thought experiment from a couple years ago was: could you create one of those laptop screen protectors where the polarization encoding was a kind of one-time pad so that only you can see the screen with a special set of glasses. So many optical effects are quantum mechanical wave interference stuff, so I have always thought of using optical effects to make it hard for classical computers to decode things.

How all of this plays out in practice would be serious research endeavours iā€™d imagine šŸ˜…
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bu5hm4nn | 4 months ago (raw) | root | parent | reply | flag 
 You could probably achieve something similar now with one of those shutter 3D glasses and a 120 Hz display. Just show the real image, then close the glasses and show the exact inverse of the real image for the second half of the 60Hz period. Should look like gray to someone without the glasses.
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hamsi | 4 months ago (raw) | root | parent | reply | flag 
 I know you can do it by just removing the polarizer and putting it on your glasses like this: https://m.youtube.com/watch?v=xQ_pkWzy0_o

But it should definitely be possible to just replace your screen with a non standard filter that requires the right glasses filter to see so its even more obscure. 

Now the real prize would be if theres a way to make it so sensitive or multi layered so that it's not feasible to brute force the encoding. I don't see much of a market for this tho. Anyone this worried about physical privacy should be worried about digital instead.