JPS5683723A - Film cassette for photographing apparatus - Google Patents

Abstract

PURPOSE: To automatically perform exposure controlling simply by mounting a cassette to a photographing device by providing photoconductors having incident ends and exit ends of predetermined directions to the wall of the cassette relating to a film cassette for endoscope photographing.

CONSTITUTION: Three pieces of photoconductors 23 of glass base for indicating the kinds of films are provided within the wall of a cassette body 15. The incident end faces 24 thereof oppose to a photographing optical path 22, and the exit end faces 25 expose to the outside surface of an extending part 17. In addition, respective photodetectors 26 are provided to the inside wall of a cassette housing chamber 12, in opposition to the photoconductors 23. If with this constitution the cassette 11 inserted with a film 19 is loaded into the chamber 12 and photographing operation is made, the peripheral light of the luminous flux enters the photodetectors 26 from the incident end faces 24. The incident light is converted to a signal by a decoder 27, and in a discriminating circuit 28, the kind of the film, for example, ASA sensitivity or the like is discriminated and the information thereof is inputted to an automatic exposure control circuit 29, whereby correct exposure is accomplished automatically.

COPYRIGHT: (C)1981,JPO&Japio