Re: [photo-3d] stereo without glasses

[Olivier Cahen <o_cahen@xxxxxxxxxxxxxxxx>]

    Yes there are some systems to show stereo in projection, without glass. They are based on lenticular screens. Images are projected from two or more projectors, each of them in a different  direction from the center of the screen. Each of these images was taken from a different direction.
    The main drawback of lenticular projection is that only from a few locations the whole image can be seen in depth. I tried it on a 4x6' lenticular screen manufactured by the late Swiss lenticular specialist Bernard Jéquier. Only five locations were convenient: one exactly under the projectors, and two on each side, closer to the screen than the central viewer location.This is consistent with the theoretical approaches.


>    Date: Thu, 11 Jan 2001 15:31:57 -0600
>    From: "Michael Galazin" <rexlion22@xxxxxxxxxxxxx>
> Subject: stereoview without viewer or glasses?
> Has anyone ever come up with a way to put a stereo image onto a screen or
> other surface which can be viewed without a viewer up against the face,
> without glasses, just viewed simply by looking at it from somewhat varying
> distances?
> If not, does anyone have any ideas, theoretically, about how it might be
> accomplished?  Does some type of selectively refracting translucent material
> exist, perhaps?
> I can recall seeing a slide projection viewer somewhere, it sort of
> projected the view onto a small screen that was an integral part of the
> viewer (like a rear projection TV, but this screen was only perhaps 5" or 6"
> across).  I don't remember if it was a stereo slide viewer or not.  But you
> could either sit close by or stand some distance away, I think, and still
> see it.  Maybe someone knows what I'm describing.  If this is a stereo slide
> unit, I'd sure like to know more about it.
> Cordially,
> Mike Galazin