Optical resonating device.

摘要

An optical laser comprises an optical resonant cavity defined by an optical fibre 1. First and second reflectors 8,13; 14,19 are optically coupled with respective ends of the fibre. The first reflector is adapted to reflect radiation at the lasing wavelength and the second reflector to be partially transparent to radiation at the lasing wavelength. Each reflector comprises a directional coupler 8; 14 having first and second pairs of ports. One each of one pair of ports 11; 16 of each coupler 8; 14 is optically coupled with the cavity 1 while both ports of the other pair 9,10; 17,18 are coupled with a respective loop of optical fibre 13,19. The remaining port 12 of one coupler 8 is connected with a source of pumping radiation 6, and the remaining port 15 of the other coupler 14 is available to output laser radiation.