Apparatus and method used for forming a matrix of dots as a latent image on photographic paper

摘要

An apparatus and an associated method for manufacturing a photographic paper. The apparatus allows a matrix of dots to be formed as a latent image on the photographic paper at a first pitch in a horizontal direction, and a second pitch in a vertical direction. The apparatus includes an exposure head which has an array of LED elements, a feed mechanism for feeding the photographic paper, a fiber array of light transmission members (second plastic fibers) arranged at a first pitch for transmitting light from the exposure head to the photographic paper, a light guide for guiding the light from the exposure head to the fiber array, and a light emission controller for energizing all the LED elements of the exposure head each time the photographic paper is fed a second pitch. The apparatus allows dots to be formed as a latent image on the photographic paper which have clear profiles and are free of density variations. This helps prevent unauthorized copying of a photographed image on the paper by an image reading device.