Optical cavity and laser

Abstract

A novel laser cavity structure is disclosed which pertains to laser resonator geometries possessing circular symmetry, such as in the case of disk or spherical lasers. The disclosed invention utilizes a very-high finesse Bragg reflector (VHF-BR) thin film reflectors of many layer pairs of very small refractive index difference, the VHF-BR deposited on a surface of revolution, thereby forming an optical cavity. These dielectric reflectors are disposed in such a way as to allow selection of preferred low order modes and suppression of parasitic modes while allowing a high cavity Q factor for preferred modes. The invention disclosed, in its preferred embodiments, is seen as particularly useful in applications requiring high efficiency in the production and coupling of coherent radiation. This is accomplished in a cavity design that is relatively compact and economical. Of particular novelty is the combination of the disclosed cavity design with polymer multilayers. The ability to deposit an unusually large number of polymer thin films without loss of specularity, while maintaining very low extinction, renders the disclosed polymer-based cavity particularly well-suited for higher mode discrimination, more rugged and light-weight cavities, as well as economical fabrication.