Miniature, optically pumped narrow line solid state laser

Abstract

A miniature solid state laser is optically pumped by ultraviolet radiation produced by a surface or corona discharge. The device is monolithic in that both the optical pump and the active medium are contiguous to a base material which is optically transparent in the ultraviolet range. The disclosed device consists of a substrate, a thin metal halide or crystalline or amorphous film deposited on the bottom of the substrate and a pair of spaced electrodes on the top of the substrate. When a high voltage pulse is applied across the spaced electrodes, discharge occurs between the electrodes and produces strong ultraviolet emissions which propagate through the substrate and dissociates the metal halide molecules in the film. This causes laser emission to occur on an atomic transition of the metal atom. The active laser medium may also be a crystalline platelet or amorphous thin film containing an impurity atom or molecule (an example would be YAG doped with Nd or LiYF.sub.4 (YLF) doped with cerium). In this case, the active medium may provide its own mechanical support, provides a surface on which the discharge may occur and thus eliminates the need for a separate optical substrate.