GB941449A - Improvements relating to stereoscopic reproduction - Google Patents

Abstract

941,449. Stereoscopic reproduction. INTERNATIONAL POLAROID CORPORATION. Aug. 31, 1960 [June 1, 1959],No. 18595/59. Headings G2A, G2E and G2J. For the production of a multicolour stereoscopic effect, a set of photographic records comprising a left pair of photographic, positionally identical records and a right pair of photographic, positionally identical records stereoscopically related to the first pair are made of a subject through filters which are, such that the records of the first pair are made respectively with light of long and short wavelengths, relative to each other, both chosen from substantially one half of the visible spectrum whilst the records of the second pair are made respectively with light of long and short wavelengths, relative to each other, both chosen from substantially the other half of the visible spectrum. The records are then projected in superposition on a screen using for each record, light of a wavelength corresponding to that by which it was made and are viewed through a viewer comprising left and right filters, the left filter allowing the passage of the long and short wavelengths in the said substantial one half of the spectrum and blocking passage of the long and short wavelengths in the said other substantial half whilst the right filter does the opposite. The use of red and orange light for the left pair of images and green and blue light for the right pair of images is referred to. Camera or projector apparatus used in the performance of the invention may comprise four entirely separate cameras or projectors. Alternatively half the number of cameras or projectors may be used, in combination with beam splitters. Filters may be used for separating out light of the appropriate wavelength or, in the case of projectors, suitable sources of light may be used without filters. The invention is stated to be applicable to cinematograph and television as well as still picture recording.