Format for color diffractive subtractive filters

Claim 1

In a color-picture transparency comprised of three superimposed diffractive subtractive filters each corresponding to a different one of three primary subtractive colors, the picture information manifested by said respective superimposed filters being disposed in substantially registered relationship with each other, the improvement wherein said color picture transparency comprises: a plastic film divided into four side-by-side regions situated between a first outer edge and a second outer edge of said film with first and second adjacent ones of said four regions located between said first outer edge and a midline halfway between said first and second outer edges and with third and fourth adjacent ones of said four regions located between said second outer edge and said midline; each one of said three filters being embossed as a relief pattern on the same given side of said film within a different one of three of said four regions; said film being first folded at the junction of said first and second regions to provide that said first outer edge substantially coincides with said midline and said given side of said first region is in face-to-face relationship with said given side of said second region; said film being second folded at the junction of said third and fourth regions to provide that said second outer edge substantially coincides with said midline and said given side of said third region is in face-to-face relationship with said given side of said fourth region, and said film being third folded at said midline to provide that said outer edges are within the interior thereof and that all three of said filters are superimposed and are substantially in registration with each other.