INSTRUMENT FOR MEASURING SCANNING CHARACTERISTIC OF LASER BEAM

摘要

PURPOSE:To accurately and rapidly measure the scanning linearity of laser beams by detecting the scanning position information of laser in the direction orthogonal to the scanning direction of the laser beams on at least three positions in the scanning direction and measuring the scanning linearity of the laser beams in accordance with respective detected scanning position information. CONSTITUTION:After setting up a scanner unit 17 for measurement on a prescribed position by a jig, mechanical dislocation amounts C1 to C3 generated by the movement of a detecting part 24 are measured in respective detecting points P1 to P3. The values C1 to C3 are inputted as correction data by means of a personal computer 35 and stored in a memory 34. The scanning position information of the laser beams in the rectangular direction to the scanning direction at least on the three positions P1 to P3 in the scanning direction of the laser beams 1 is respectively detected and the scanning linearity of each laser beam is measured in accordance with each detected scanning position information. Consequently, the scanning linearity of a laser beam L reflected by a rotary polygon mirror 12 e.g. and straight scanning the surface to be scanned can be accurately, rapidly and automatically measured in accordance with a practical used product.