Abstract

Nd:YAG lasers have numerous industrial and scientific uses; recent industrial applications have called for more output power. As cw devices, CO₂ lasers are used in industry providing multikilowatt output power and a low-divergence beam. However, considering the lasing wavelength and utilization of optical fibers, Nd:YAG lasers are still preferred as laser sources. There have been a few attempts to obtain kilowatt power with solid- state materials, especially Nd:YAG. One is a slab geometry laser which can reduce the thermal effect in the material, but the size of the Nd:YAG boules limits the maximum slab size. The kilowatt slab laser needs more development time. The other approach is a multiple-rod geometry laser. Commercially the maximum rod size is 8 mm in diameter and 150 mm long. This size rod pumped by two krypton arc lamps can produce ~0.4 kW. If one needs more power than that, it is practical to use a multiple-head configuration. We had previously succeeded In producing 1-kW cw output with a three-head oscillator, but this configuration had an unstable point in the working output range.

© 1988 Optical Society of America