GB346679A - Improvements in or relating to stereoscopic photography - Google Patents

Abstract

346,679. Stereoscopic photography. SAVAGE, L. F., 20, Old Compton Street, London. Oct. 10, 1929, No. 30808. [Class 97 (i).] In apparatus for the production of stereoscopic pictures by the use of optical systems of the kind described in Specifications 299,733 and 300,143, [both in Class 97 (i), Optical systems &c.], in which the images are superposed on the focal plane, the angle of convergence of the rays of light from the objectives to the images are caused more nearly to correspond to the angle of divergence of the rays of light from the objectives to the object by the introduction of rhomboidal prisms into the ray path. In the Figure the prisms d are introduced between the objectives a and the lens b in which the first image is formed. The distance between the subsequent lenses e is thus reduced to a minimum, together with the diameter of the superposing lens f. In a modification the prisms may be arranged in front of the objectives a, and in a further form the prisms are arranged between the lenses e and the superposing lens f. In further modifications a single rhomboidal prism is used and is rotated to be positioned alternatively in the axis of each optical system. This prism may be rotated together with a single back lens e, being situated between the objectives and this lens or may be independent of the back lenses e and rotated between them and the superposing lens.