Abstract

Solid state lasers are promising for material processing applications because of their compactness, easy maintenance and focusability compared to another widely used CO₂ laser. To expand application fields of solid state lasers, development of the high average power and high beam quality laser is most desirable. Further more, because the optical fiber can transmit the near infrared light from the solid state lasers, the optical system should be simple and flexible. Recently, a multikilowatt Nd:YAG laser has been reported with four YAG rods in series.¹⁾²⁾ The rod type laser, however, suffers from strong thermally- induced beam distortion causing the instability of the laser and the degradation of the beam quality.

© 1988 Optical Society of America