Photosensitive material detecting apparatus

摘要

A photosensitive material detecting apparatus having a single or a plurality of optical sensor(s) disposed at a selected location on a transport path of a photosensitive material and (each) including a light emitter and a light receiver for optically detecting the photosensitive material. This apparatus includes a pulse generator provided for a drive motor associated with the transport path. The pulse generator generates a pulse signal synchronized with rotation of the drive motor. The light emitters emit pulsed light whose intervals between ON periods are controlled on the basis of the pulse signal, such that the pulsed light has short intervals when the photosensitive material is transported at high speed and long intervals when the photosensitive material is transported at low speed.