Abstract

The variable-configuration multirod resonator (VCR)¹ consists of three Nd:YAG rods in a folded cavity so that each rod is end pumped by a fibre coupled diode laser. The VCR can be constructed with a total cavity length as short as 64 cm, in a square measuring 12 cm by 20 cm, and gives a high power fundamental mode output, with a very high efficiency (slope efficiency of 51% and optical efficiencies as high as 37%). It is capable of running in either Fabry-Perot or ring configuration¹. In the case of the Fabry-Perot resonator, the output consists of two orthogonally polarised components and in the ring resonator the output consists of two circularly polarised components with opposite sense. We discuss here, techniques that can be used to obtain linearly polarised output from the VCR whilst maintaining the exceptional qualities of the VCR. Of the seven or more configurations constructed, the three most significant are shown in Fig. 1.

© 1998 IEEE