Focusing of a 7700-Å high power phased array semiconductor laser

Abstract

A high power (200 mW/facet) phased array semiconductor injection laser consisting of multiple optically coupled 7700-Å emitters is focused to obtain over 90 mW in a single nearly diffraction limited 2.5-μm-diam spot. Focusing is accomplished by imaging the vertical near-field and the lateral far-field patterns. Such an optical system functions only when the emitters are mutually coherent, as with this device.