Laser Welding in Automatic Assembly Line for Color-CRT Electron Gun

Abstract

YAG laser welding technology has been applied to an automatic assembly line for newly designed color-CRT electron gun. In the laser welding line, optical fiber delivery systems are used. This fiber is made from pure fused quartz. It has a 400 μm core diameter and a ten meter length. In using the optical fiber system, experiments are made to determine laser damage threshold in the fiber material versus high laser power density. transmission characteristics, life test and mechanical strength test. The develpment of this technique enables the laser optical system to be simplified, with higher flexibility, compared with coventional laser welding system using mirrors. In addition, simultaneous multi-spot laser welding and laser marking optical systems were developed. This welding line has markedly raised the productivity with higher product quality and reliability level.