| 摘要 |
1,190,913. Three dimensional cinematography; halography. COLUMBIA BROADCASTING SYSTEMS INC. June 15, 1967 [Sept. 8, 1966], No.40202/66. Headings G2C; G2E and G2J. A projection screen 1 is made as a "deep" hologram for use in the projection of three-dimensional colour of monochromatic pictures using white light, comprises a photographic medium with a resolving power at least equal to a wavelength of light (about 0.5 micron) and several wavelengths thick, say 20- 40 microns, the medium being first exposed to coherent radiation converging towards an image of a first projector Pr I simultaneously with coherent radiation issuing from images of viewing zones associated with the first projector, and secondly being similarly exposed in relation to a second projection, Pr II. Left and right-eye pictures are projected on to the concave screen 1 by the two projectors in white light, Pr II being optically displaced by mirrors M 1 M 2 , and are viewed as a steroscopic picture, without spectacles or other aids by viewers within zones consisting of parallel strips extending back from the screen. These strips are the inter-ocular spacing in width and may consist of spaced or continuously extending L and R pairs. The exposure in turn of the rear face of the screen to light converging towards each projector is achieved by the optical system of Fig. 6 (not shown), segments of the screen being exposed and developed in succession. Light from laser (6) is split into two beams, one being focused towards virtual image (Pr) by lenses (4, 5) on either side of screen (1), or the other being focused on the screen by lens 5 as an image of a model 15 of the viewing zones of the auditorium. The model may be a diffusing screen masked to produce the zones. The angular separation of the projectors # is given by 1 # (/nd)<SP>2</SP> where = vacuum wavelength of light n = refractive index of emulsion d = thickness of photo-sensitive layer. |
