Optical scanner using planar reflection holograms

摘要

An optical scanner suitable for use with a bar code reader includes a light source for generating a laser beam, a laser beam scanning device, a scanning pattern generating optical system, and a signal light condensing optical system for deflecting scattered signal light scattered by an object to be read to introduce the light to a photo-detector. The scanning pattern generating optical system or signal light condensing optical system includes strips of planar reflective holograms disposed substantially in parallel with each other in one plane to produce a reflection beam having an angle of reflection which is different from an angle of incidence of the laser beam thereon. Another embodiment discloses a condenser integrated with one of plane mirrors for deflecting the scan beam to form a hologram module of the reflection type. The scanner is a miniaturized apparatus as a result of the reflection holograms.