Minolta Camera Kabushiki Kaisha

Hidetoshi Yasumoto

Yoshio Yuasa

Nobukazu Kawagoe

Kazuhiko Naruse

Masahito Inaba

In a light source device in which one or more light emitting tubes are adapted to emit light sequentially, there are provided one or more counters for counting the number of times of failure of light emission of the light emitting tubes, and comparator or judging circuit for comparing the number counted by the counters with a predetermined number to produce an interruption signal when the counted number is over the predetermined value, a control unit acts to interrupt the light emission of the light emitting tube in response to the interruption signal and a warning device is activated for indicating a warning in response to the interruption signal.

Light source device

An enlarger for copying a film is provided having two modes of operation. A first mode of operation permits preliminary adjustment of the focus of the lens system while the second mode of operation permits an actual exposure, the first mode of operation being inhibited during the actual exposure of the film in the second mode.

Enlarger for use in photography

An enlarger for use in photography capable of printing a color copy from a color original film includes a light source for generating a plurality of primary colors and a microcomputer for controlling the light source. The microcomputer has various functions which are: for providing a plurality of exposure data corresponding to a plurality of primary colors; for designating at least one of the primary colors; for altering the exposure data corresponding to the designated primary color; for displaying an information relating to the exposure data to be altered; for indicating the direction of change in tone of the color copy caused by altering the exposure data; for selecting the type of the original film; and for controlling the relation between the direction of change in tone of the color copy as indicated and the direction of change in the exposure data as displayed in response to the selected type of original film.

A color enlarger for use in photography capable of printing a color copy from a color original film includes a plurality of source lights for separately generating lights corresponding to a plurality of primary colors; a monitor for separately picking-up the plurality of source lights to monitor the light generated from the light source, and light measuring circuit for separately measuring the plurality of source lights transmitted through the color original film. The color enlarger further includes a microcomputer which has various functions which are: for providing a color data representative of a color to be reproduced on the color copy; for separately calculating the whole light quantities for the plurality of source lights to be generated upon printing the color copy, in response to the monitor, the light measuring circuit, and the provided color data; and for controlling light sources upon printing the color copy in response to the calculating value.

Color enlarger

Light source for exposure

An improved enlarger for producing prints from an image bearing negative includes a film carrier, an enlarging lens, a light source, and a supporting pole for moving the elements to different operative positions. The apparatus is provided for inputting a signal representative of the focal length, and detectors are provided for determining a first and second datum position with the enlarging lens focused at each position. The information representative of these positions can then be used to automatically provide an in-focus position for the enlarging lens at a desired magnification level when the film carrier is subsequently moved.

Automatic focusing device for an enlarger

Disclosed herein is a light measuring and control data calculating device for use in a photographic enlarger. The device comprises first light detecting means for detecting the amount of light emitted from a light source, second light detecting means for detecting the emitted light amount at a position on the surface of an easel through the optical system and an original film in the enlarger, setting means for manually setting a preliminary desired amount of light to be emitted from the light source and calculation means for calculating an actually desired amount of flash light to be emitted from the light source for obtaining a desired total amount of the exposure light on the surface of the easel for making a suitable exposure on the printing paper to provide a best print.

Growing community of inventors

Tondabayashi, Japan

Hidetoshi Yasumoto