US 6,384,896 B1 · Microfilm search device

Abstract

A microfilm search device for distinguishing presence of frames from a change in quantity of transmitted light between the opposed optical fiber end faces between which a microfilm is placed. A pair of opposed blocks for holding optical fibers are arranged across the microfilm in a width direction with placing the microfilm therebetween. Light is guided into the optical fibers held by one block from a light source, passes through the microfilm, and enters the optical fibers held by other block. A quantity of entered light is detected by photosensor and an output thereof is binarized. Based on binarized signals, the presence of frames is determined. End portions of optical fibers on the side of the light source are bunched, and a bunched portion is detachably and non-rotatably held relative to one lamp. Frame detection condition due to light quantity can be uniform and maintained easy after disassembly, inspection, maintenance of the device. The each block comprises a metal plate opposing to the film surface and a resin integrally molded on the backside. A surface of the metal plate is polished. The damages of film and/or the end faces of the optical fibers during high-speed running of the film are prevented.

Claims8

Dependent claims

A microfilm search device for distinguishing presence of frames from a density change in a running direction of a microfilm and searching for a desired frame from the microfilm, comprising:

a first block arranged across the microfilm in a width direction;
a second block arranged across the microfilm in the width direction, end faces of the first and second blocks being opposed to each other with the microfilm placed therebetween;
first optical fibers whose end faces pass through and are held by the first block;
second optical fibers whose end faces pass through and are held by the second block, the first and second optical fibers are opposed to each other while the microfilm is placed between the end faces in different positions in the film width direction;
a light source used in guiding light to said first optical fibers;
a photosensor for detecting a quality of light incident on said second optical fibers;
a binarizing section for binarizing an output of the photosensor;
and
a searching section for determining the presence of frames based on binarized signals to perform frame search;
wherein end portions of said second optical fibers are bunched on the side of said light source, and a bunched portion is detachably and non-rotatably held relative to one lamp incorporated in said light source and said bunched portion has a protrusion that engages with a box containing the lamp and preserves the relative orientation of the fibers with respect to the lamp.

7 more elements

Dependencies are inferred from the claim text.

Microfilm search device

Life of this patent

Microfilm search device

Life of this patent

Abstract

Claims8