GB746562A - Improvements in or relating to photographic type composing machines - Google Patents

Abstract

746,562. Photographic type-composing. MERGENTHALER LINOTYPE' CO. Apri 1 1954 [May 13, 1953], No. 12551/54. Classes 97 (1) and 98 (1). In a photographic type-composing machine in which any one of an array of characters on the front plate 1 may be projected through projection lens 11, a collimating lens 10a is provided for each character so that pencils of parallel light, each pencil consisting of parallel rays from each point on the character, are incident on lens 11 and the image of each character is thus correctly presented for photographing at a predetermined position in a fixed plane. In the forms shown in Figs. 1 and 5, crossed Venetian blind shutters 8, 9 allow the light from source 5 to pass through a selected character, the corresponding, collimating lens 10a and projection lens 11, and to form an image, as shown in Fig. 1, on a ground glass screen 2. Lens system 4 is adjustable to produce a magnified or reduced image of the character on a photographic film 3. The lenses 10a and characters are arranged in parallel planes and the distance between,them is equal to the focal length of the lenses 10a. In the described embodiments the pencils of rays from corresponding points on the characters must be parallel. A honeycomb structure 12 may be provided to prevent light .from a selected character entering lenses 10a other than its own. As shown in Fig. 3, a pair of electromagnets 8c may operate each shutter by means of a link 8h and a crank-arm 8g attached to the shutter pivot p. In the form shown in Fig. 5 the image is formed in space and is then magnified or reduced by lenses 15a and 15b which are components of a type of eye-piece, usually used in telescopes or microscopes and with lens 16 form the required image on the film 3. A filter 17 may be provided and in a modification the optical system is arranged so that different point sizes can be obtained by using different lenses which are prepositioned and arranged in lens mounts or in lens turrets so that they can be brought into the operative position ,when required. Filters, similarly mounted, may be provided.