Abstract
The purpose of this study is to develop a new surface polishing method for water-soluble single crystal. It is impossible for a water-soluble single crystal to machine by laser beam in the air because of its brittleness. Therefore, the water-soluble single crystal is irradiated by the YAG laser beam in the saturated solution. The temperature of the water solution is raised by the heat of YAG laser beam, and the crystal is dissolved in the water solution then, the surface is processed. In this study, the KDP crystal is chosen as a water-soluble single crystal because it is difficult for KDP crystal to obtain constant dimensions and surface roughness by the conventional various processing methods. In the experiments, the processed roughness of KDP crystal is measured, and it is compared with the conventional polishing method. In addition, the surface of KDP crystal is evaluated by the performance of second harmonic generation.
