Immersion method and apparatus for cooling a semiconductor laser device

Abstract

An immersion cooled semiconductor laser assembly includes an electrically activated semiconductor laser device, such as a two-dimensional laser diode array, and liquid coolant flowing thereabout which directly contacts the emitting facet of the semiconductor laser device. The semiconductor laser assembly also includes first and second electrodes for supplying electrical energy to the semiconductor laser device such that the semiconductor laser device emits a laser output through its emitting facet. During the emission of the laser output, however, the semiconductor laser device generates heat, thereby increasing the temperature of the semiconductor laser device. In order to protect the semiconductor laser device, the circulating liquid coolant draws heat from the semiconductor laser device, thereby cooling the semiconductor laser device. The liquid coolant can be a dielectric liquid coolant which is both electrically and optically passive so a to maintain electrical isolation between the first and second electrodes without absorbing the laser output of the semiconductor laser device. By efficiently cooling the semiconductor laser device, the semiconductor laser device can consistently product output pulses having a relatively high average power and a relatively high pulse repetition rate.