GB1407085A - Optical systems for photography and the like - Google Patents

Abstract

1407085 Optical systems for photography and the like RANK ORGANISATION Ltd 23 Aug 1973 [19 Sept 1972] 43279/72 Heading J An optical system comprises a basic first housing 30, Fig. 2 incorporating a front lens unit, preferably a zoom lens 10, Fig. 1, a beam-splitter 18, a viewfinder e.g. Galilean telescope 20 receiving light from one output of the beamsplitter, and an optical outlet receiving light from the second output of the beam-splitter; a second interchangeable housing or module 32, incorpor ating an optical input for light to a rear lens unit 22 with means for receiving an image therefrom; and means for detachably securing the housings together with their optical outlet and input contiguous whereby alternative rear lens units and/or imagereceiving means may be used. The basic front lens and viewfinder housing may be connected to an optical module in housing 32 containing mirror 24 reflecting the light on to a still cassette film 26, or a mirror 24a reflecting the light on to a cine film 26a, or in Fig. 2 a mirror 24 reflecting light on to a film cartridge of which the spool engages a wind-on lever 36. Fig. 3 (not shown), shows a module containing a driven cine film cassette (40). The module may house a television pick-up tube. Mirrors 24, 24a may be partially reflecting to allow light to be tapped off for an exposure control. An iris diaphragm in the zoom lens or in front of the rear lens in collimated light passing through the contiguous outlet and input may be linked with a scale of the module, while a shutter is also provided adjacent the rear lens.