抄録
In order to realize fine processing with a high precision optical system, we have developed a laser processing system with galvanometer scanners and optical lenses using a shrink fitter. The shrink fitter was used to fix the optical lenses to the housing by shrinkage fit. Thus the optical axes of the lenses coincided with each other. If the temperature of the lenses increases, the optical axes of the lenses will get out of the line because the thermal expansion of the lens is greatly different from that of the housing. The shrink fitter prevents the misalignment of the lenses at the elevated temperature. Therefore fine laser spots can be obtained over the quite wider scanning width, even at elevated temperature. We examined the possibility of application to laser processing of this lens system using the shrink fitter. Diameters of the lenses used in this study were 160 mm so that the laser spots could be scanned over the width of 100 mm, both directions of the X-axis and Y-axis. YAG laser was used. The sizes of the YAG laser spots at the image plane were measured by the beam scan, within the scanning area of 100 mm x 100 mm. And the measured sizes of the laser spots were compared with the calculated sizes of the laser spots. The distortion behavior of the laser beam was also measured. As the result, it turned out that the sizes of the laser spots at the image plane were small enough even in the case of the laser processing.
