It's not even close to this simple.Jotham said:Close, but then you mention overlapping images and the need to stitch them back together. Alot of people are also mentioning lens, etc. I think the actual implementation would be alot simplier, especially considering how small it would need to be. Simply stick a single pixel sensor (CCD) at the end of a narrow tube so only light parallel to the tube (perpendicular to the surface as you said) can reach it. Now this doesn't record an image but just the color at that pixel co-ordinate - now do this for every pixel and you have a screen-resolution copy of what is infront of the screen -- no zoom ability and focus would be only good for close range (this think isn't going to do landscape photography), but no stitching, processing, etc to worry about either). Sounds ideal for video-conferencing.
If you do this with a single-pixel sensor behind each element, you'll get an array of pixels with a large (proportionally) gap between them. It will be like imaging something though a screen - meaning all kinds of alias effects. If you interpolate to fill in the gaps, you'll end up with a pixelated image.
If you put a more robust sensor (capable of imaging more than one pixel), it will improve, but now you're stitching together images again.
All of this ignoring, of course the fact that screen resolution is pretty terrible. Especially if you want to zoom the image (necessary if you don't want to force everybody to sit a precise distance from the screen in order to fill the image.)
Go for it. But I think you'll discover a lot of really hard problems. Obvious isn't always viable.Jotham said:Side view:
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This little tube sensor would be packed in the LCD array along with the standard Red, Green and Blue sub-pixels which make a single pixel, thus creating a display that can capture as well as display.
PS. If this isn't how they do it, maybe I should get to the patent office quick - though this is kinda the obvious way to do it.