Vertical-cavity surface-emitting laser (VCSEL) with cavity compensated gain

Abstract

In one form of the invention, there is provided a laser comprising a front mirror and a rear mirror which are disposed so as to establish a reflective cavity therebetween; a gain region disposed between the front mirror and the rear mirror, the gain region being constructed so that when it is appropriately stimulated by light from a pump laser, the gain region will emit light; one of the front mirror and the rear mirror is substantially fully reflective at the lasing wavelength and the other of the front mirror and rear mirror being partially reflective at the lasing wavelength so as to allow a beam of laser light to be emitted therefrom; and an intermediate mirror disposed between the rear mirror and the front mirror, at least a portion of the gain region being disposed between the rear mirror and the intermediate mirror, the rear mirror and the intermediate mirror being reflective at the pump wavelength and being spaced from one another so as to cause the pump light to be reflected between the rear mirror and the intermediate mirror so that the pump light will make multiple pumping passes through the gain region, whereby to yield an increased observed, or “wall-plug”, efficiency. In one preferred form of the invention, the gain region is formed by multiple quantum wells (MQW) which act as the intermediate mirror.

Dependencies are inferred from the claim text.