GB482360A - Improvements in stereoscopy in cinematography - Google Patents

Abstract

482,360. Stereoscopic kinematography. MOOS, N. H. June 24, 1936, No. 17505. Void. Convention date, July 23, 1935. [Class 97 (i)] Relates to stereoscopic kinematography and comprises (1) means for taking and projecting pairs of images on lenticular films, line-screen films, &c., (2) cameras having optical systems with two converging axes, and (3) projectors with optical systems, gates, &c., for two images, and means for feeding one image at each film shift ; complementary colour filters may be used for image separation. (1) Linescreen and lenticular films, as used for colour kinematography, may be exposed with two lenses or with a large-aperture lens having a mask 1, Fig. 1, providing exposure apertures 2, 3, and may be projected with a screen comprising two parts of complementary colours used as in colour projection. (2) Figs. 5 and 7 show a camera comprising vertically-spaced lenses 10, 11, having reflecting prisms 13, 13a before them and receiving beams from reflecting prisms 14, 14a having spaced centres on one horizontal line. Changeable prisms 16, in a housing 17 in front of the prisms 14, 14a may effect convergence of the taking axes as desired. A screen 25 extends between the lenses and the image areas of a double gate 21, and simultaneous exposure is effected by a rotary shutter 22; film shifts may be made at half the normal frequency and may feed two images at a time. A modification is described in which exposures are made through a singlepicture gate by a lens having a rotary, counterweighted, periscopic combination of prisms before it, gearing being provided between the shutter, periscope, and feed claw, to effect one exposure after each film shift, and with the periscope extending horizontally in one direction or the other ; the taking axes in the two positions may converge. (3) Fig. 10 shows a two-picture gate 41, 42 and a lens system for use in a standard projector. Two lenses are carried by one mounting 43 carrying also parallel-faced elements 45, 45a of which the element 45 is rotatable on a pivot 46 to effect superposition of the images on the screen. The rotation is effected by a lever 47 spring- pressed on to a threaded rod 50 manually rotatable. Each image is projected twice, once with the preceding image and once with the following image. The film images may be dyed in complementary colours, or colour screens may be provided in association with the lenses.