Dainippon Screen Mfg. Co., Ltd.

Ikuo Sho

Kazuma Kan

Koichi Isono

Masakazu Ohtorii

Takamichi Nishihama

Photosensors having light emitting elements and light receiving elements are provided in a path for carrying a film. The light emitting elements emit periodic pulsed light. When the film is present in the positions of the photosensors, the periodic pulsed light is reflected by the film to enter the light receiving elements, whereby presence of the film is detected. Activation time and activation interval of the light emitting elements for generating the periodic pulsed light are determined so that accumulated exposure value in each portion on the film is less than a critical exposure value of photosensitive material provided in the film.

Method of and apparatus for detecting presence or absence of

A copying machine has a camera unit and a developer unit connected through a coupler, wherein the coupler includes feed paths along which a length of film is fed before and after exposure to a focused image of an original; a film cassette located adjacent to the feed path; a film carrier for supplying a length of unexposed film to the photographic or camera section, the film carrier being capable of running to and fro along a portion of the feed paths; an overlay sheet holder provided in opposite to the film carrier and movable in synchronism therewith; a transparent platen on which the film is placed with an overlay sheet covered thereon to shut out extraneous light; and a film sucking means mounted on the film carrier whereby a length of film after exposure is fed to the developer unit by being held by suction at its terminating end.

Growing community of inventors

Shiga, Japan

Ikuo Sho