Abstract

The Nd:YAG laser marker utilizing a liquid-crystal-device (LCD) mask is characterized by its capability for freely changing mask patterns within a short period.' It requires a linearly polarized beam. To increase marking repetition rate and/or to mark a larger image, a high power Nd:YAG laser is needed. However, when the laser power is increased, heat generated in the NY:YAG laser rod induces stress which leads to strong birefringence in the rod.² Consequently, the polarized beam profile is distorted, which makes marking a clear image difficult. We have developed a novel laser marker that can mark dear images.

© 1992 Optical Society of America