SHEARING RADIATION BEAM FOR IMAGING PRINTING MEDIA

摘要

An illuminator (10) for producing a radiation spot (120) on a workpiece (1 10) comprises a laser light source (20) and a beam-shearing optical system (30). Fine structure (160) generated by an integrator (80) of laser light source (20) in integrated beams (90) as a result of path length differences among coherent light beams (70) from emitters (60) of lasers (40) is sheared by the inclusion of beam-shearing optical system (30) into illuminator (10). Beam- shearing optical system (30) allows illuminator (10) to produce a radiation spot (120) in which the fine structure (160) is spread so that scanning of radiation spot (120) does not produce the striations (140) in scanned patch (170) that are obtained with prior art illuminators.