Patent ID: 6066846
Filing Date: 2000-05-23
Classification: H04N

Abstract:
A light beam scanning apparatus comprising:a medium to be scanned;a reference grating;an elongate light guide rod extending along said reference grating and supporting a pair of photoelectric transducers mounted respectively on opposite ends thereof; anda scanning optical system for guiding a synchronizing light beam to said reference grating to produce a pulsed synchronizing light beam which is introduced into and travels through said elongate light guide rod to said photoelectric transducers for thereby generating a synchronizing signal, and also for guiding a scanning light beam to said medium to record image information on or read image information from said medium according to said synchronizing signal;said elongate light guide rod having a convex entrance surface for introducing said pulsed synchronizing light beam therethrough into the elongate light guide rod, a substantially planar rear surface confronting said entrance surface for receiving the introduced pulsed synchronizing light beam, and a diffusion surface disposed on said rear surface and extending longitudinally of said elongate light guide rod, for diffusing the pulsed synchronizing light beam applied to said rear surface.