Masami K Tawara

US Patent:

57104182, Jan 20, 1998

Filed:

Nov 3, 1995

Appl. No.:

8/552573

Inventors:

Masami Tawara - Old Tappan NJ

International Classification:

G06K 710

US Classification:

235472

Abstract:

An optical image sensor, particularly a bar code reader, comprises a laser diode emitting a light beam of small area and elliptical cross-section. The light beam is directed onto an optical device for greatly expanding the beam along one axis for expanding the beam cross-section to that of a greatly elongated rectangle having a line-like shape. The line beam is projected from the reader for encompassing and illuminating the entire width of a bar code. Light reflected from the bar code is focused as a complete image of the bar code onto a light detector for simultaneous storage of all the bar code data. The beam expander can comprise a cylindrical lens, a cylindrical mirror, or a conical mirror including means for varying the intercept of the laser beam with the conical surface for selectively varying the width of the expanded beam.