Patent ID: 6674517
Filing Date: 2004-01-06
Classification: B65H,G01P

Abstract:
An optical motion detector comprising:a light-emitting device; a collimator lens for collimating a light beam emitted from the light-emitting device; an object lens, which concentrates the light beam collimated by the collimator lens and applies the light beam to a measurement object that moves in a prescribed direction, forming a light spot that has a prescribed spot diameter on the measurement object; a beam splitter, which splits a reflected light which belongs to a reflected light from the light spot of the measurement object and is concentrated via the object lens; a light-receiving lens, which concentrates the reflected light split by the beam splitter; two pinholes, through which reflected lights pass, wherein the lights belong to the reflected light concentrated by the light-receiving lens and come from two regions inside the light spot located at a prescribed interval on a straight line parallel to a measurement object travel direction; two light-receiving sections on which the reflected lights, which have passed through the two pinholes, are respectively made incident; and a measuring section, which measures at least one of a travel speed and a quantity of movement of the measurement object on the basis of outputs of the two light-receiving sections.