back-project screen material?

[P3D Richard Young <young@xxxxxxx>]

I need to do back-projection using passive stereo. Our current set-up is
35 mm slides with two Kodak Ektagraphic projectors, using linear polarizers
on the projectors and a good pair of linear polarizing glasses on the
viewing side of the screen. We need both clarity of image, and good
off-axis viewing (the image needs to be seen clearly at up to at least 60
degrees of the central viewing axis). I have sampled
all conventional off-the-shelf screen materials sold by screen makers for
this purpose, and have not found any which sufficiently preserves image clarity,
good off-axis viewing, and the polarization of the light. I have also tried
some different acrylic plastics with various pigments put in them, which give
good off-axis viewing and preserve polarization, but which lead to an
unclear, diffuse image. Can anyone recommend any material for this purpose
which they have found to work well? I have heard ground glass does the job,
but we are using a 6 foot by 6 foot screen that needs to be transported, and
glass that size would weigh too much and be too fragile.





- Dick Young |:)
young@xxxxxxx

Q. What did the Zen Buddhist say to the hot dog vendor?
A. "Make me one with everything."

To be viewed in stereo:

  .   .   .   .   |  .    .  .   .
  .        .      | .          .
     @@@@@        |        @@@@@
  . @ o o @    .  |   .   @ o o @  .
 .  .  =    .     | .  .     =   .
   .   .       .  |  .   .        .
 .         .      | .        .

Hint: fuse both the faces and the "stars"
(thanks to Jennifer Leong, N.Y.U., with modifications)



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