| 摘要 |
PURPOSE:To reduce power consumption and enable a smaller laser oscillator to be used, by providing a mask plate on the outside of a transmitting mirror, providing the mask plate with through-holes corresponding to symbols, and providing the mask plate with a reflective surface on the surface thereof opposed to a reflective mirror. CONSTITUTION:The surface of a mask plate 14 comprises a reflective surface 20 and through-holes 19. A total-reflection mirror 6 and the reflective surface 20 constitute a pair of resonators. When glow discharge is developed in a laser oscillator 1, an excitable gas 8 is excited to generate a laser beam 21. When the laser beam 21 passes through the through-hole 19, the beam 18 is projected on a work 23 through a condenser lens 22 to mark a symbol on the work 23. When the laser beam 21 is reflected by the reflective surface 20, the beam 21 is returned into the excited gas atmosphere, is amplified by stimulated emission, and is then again projected on the mask plate 14. Thus, the laser beam 21 is utilized for amplification, so that electrical energy inputted to the laser oscillator 1 can be reduced. |
