Laser diodes semicircular side-pumped laser rod with a round-sharped output

In order to keep the symmetric of the pump geometry and obtain a low‐level, high quality laser output, the temperature of the side‐pumped laser rod is more often be controlled by a water cooling system than a conduction cooling system in the diode‐pumped solid‐state lasers. But the use of the water cooling system increases the volume and decreases the mobility. To solve the confliction between the beam quality and the mobility of the laser system, a novel, compact and all‐solid design of the pump structure is applied to the side‐pumped laser system. The Nd:YAG rod is pumped by semicircular mounted LD arrays inthe pump module, and two pump modules are working together to compensate each other. Numerical calculation and experiment are performed, the output laser has a round‐sharped beam with a beam waist of 5 mm and a divergence angle less than 7 mrad, and a maxim output pulse energy of 75.8 mJ is obtained under the working frequency of 20Hz, the slope efficiency is 35.8%. (© 2006 by Astro, Ltd. Published exclusively by WILEY‐VCH Verlag GmbH & Co. KGaA)