GB423629A - Improvements in and relating to kinematographic projection apparatus - Google Patents

Abstract

423,629. Colour kinematography. CALLIER, A., 38, Boulevard Albert, Ghent, and GILBERT, F. HEGER-, 82, Rue Joseph Bens, Brussels, both in Belgium. Dec. 22, 1933, No. 36123. Convention date, Dec. 24, 1932. [Class 97 (i)] Four images are projected through two pairs of complementary colour filters by means of prism systems which separate the image beams so as to enable normal lenses of relatively large aperture to be used. As shown in Fig. 1, two pairs of complementary colour records, side-by-side, and side uppermost on the film, are projected simultaneously by four prism systems and separated lenses 18 ... 21. Each prism system comprises a right-angle prism 16, a roof prism 15, and a right-angle prism 17, cemented together, and rotates the image beam through a right-angle about its axis. The members of the pairs of records may be erect, and arranged in series in a single rank on a film, and may be projected with the aid of two rhomboidal prisms which displace the two central image-beams in opposite lateral directions. The Specification, as open to inspection under Sect. 91, describes also the use of four rhomboidal prisms in the projection of pairs or erect images in two ranks on the film, the use of a pair of projection lenses of different focal length from the other pair, so that, when the pairs of images have been taken successively and are projected simultaneously, one pair of images may be projected out of focus, and an optical system for use in a camera. The camera system, Fig. 1 (Cancelled), comprises a prism 2, with a transmitting-reflecting surface 2<a> and a totally reflecting surface 2b, and lenses 5, 6, and colour filters 7, 8, to produce images on a film 9. The lenses 5, 6 are separately adjustable for focusing by means of tubes 12 having an external thread engaging a support 11, and an internal thread engaging the lens tube. To prevent variation in the relative sizes of the images produced by the two lenses, as the focus of the lenses is altered while the subject being photographed moves towards the camera, additional lens systems 10 are provided in front of the lenses 5, 6. Each system comprises a positive and a negative lens, and the positive lens 10<b> of one system and the negative lens 10<a> of the other system are connected, as shown, to the tubes 12, so that the separation of the lenses in each system 10 varies as the focus of the lenses 5, 6 is varied. The systems of lenses 10<a>, 10<b> may have no power when the lenses 5, 6 are focused for infinity, and the power of one may increase and of the other decrease, during adjustment of focus of the lenses 5, 6. Alternatively, the powers may both decrease, or may both increase, or one system may be dispensed with. This subject-matter does not appear in the Specification as accepted.