From: Paul Cousoulis 
To: Harold , atm{at}shore.net
Reply-To: Paul Cousoulis 


No, You can't even get a holograph to 'project'. When you look into a
hologram, the light comes straight out or straight through the media. You
can't get the hologram to appear outside the edges of the media. If the
hologram is on sheet a paper, some objects may appear in front of the
paper, while other objects appear to be behind the surface of the paper,
but you can't turn the paper edge on and see something floating above it. A
hologram works on the same principles as a telescope mirror. A bigger
aperture has a higher resolution because the light at the edges of the
mirror interact to form diffraction patterns which result in the images we
see. At the limits of resolution we see the Airy disk which is the
diffraction pattern of a point source of light. A hologram uses a film
where there is a front surface and a back surface. Light from the back
surface interacts with light from the front surface to create diffraction
patterns which our eyes see as images. Each eye sees a different pattern
creating an illusion of three dimensions. There is no real projection.


Paul

Harold wrote:
>
> > Is this possible??
>   If holographic technology can project images of a solid object. What would
> happen if you project a lens as the object, would it  function just like a
> refractive objective lens where it can capture  light and converge it into a
> point?
>  Someday, when you want to use a refractor, maybe you can just flick  on a
> swith and the lens would be projected with 0 wavefront error and fully
> multi-coated (holographically). Is this technology possible someday? What do
> you think?? >>
>
>    The above is a question that was posed by a member of  less technical
> minded telescope group.I thought the idea interesting.but don't even have
> knowledge to  adaquately to answer it and so far none in that group have
> offered up any answers. Thought i would present his querry here as it may be
> of interest to the more techincal minded.

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