Flexure-mounted external cavity for single-mode operation of semiconductor diode lasers

The construction of a short external cavity (SXC) module based on the flexure mount concept for semiconductor lasers is presented. The SXC system is an inexpensive and simple means to achieve single-mode operation from normally multimode lasers. The SXC assembly is a flexure mount designed to hold an external cavity mirror and a laser in alignment. The flexure mount permits easy and precise angular positioning of the external mirror. With InGaAsP lasers, side mode suppression ratio as high as 300 can easily be obtained.