Enhancing beam quality and optical intensity of partially coherent VCSEL array by on-chip integrating micro optical phase modulators

Abstract

Micro electronically controlled liquid crystal optical phase modulators (LCOPMs) are on-chip integrated with partially coherent vertical cavity surface emitting laser (VCSEL) array to improve the array's beam quality and optical intensity. The initial phase shift among array elements introduced by imperfect fabrication is compensated by adjusting the voltages loaded on the LCOPMs. Experimental results show that the beamwidth of the VCSEL array is reduced by 28% and the intensity ratio of the central lobe to the secondary lobe in the far-field is increased by 50% after phase compensation by the LCOPMs.