Author(s): Chen, A (Chen, Ao); Zhang, WQ (Zhang, WeiQiao); Zhou, XY (Zhou, XuYan); Liu, J (Liu, Jing); Zheng, WH (Zheng, WanHua)

Source: JOURNAL OF OPTICS Volume: 26 Issue: 4  Article Number: 045607  DOI: 10.1088/2040-8986/ad2a21  Published Date: 2024 APR 1 

Abstract: The spatial coherence of filaments in edge-emitting broad-area semiconductor lasers (BALs) is studied based on speckle theory, and a passive speckle suppression method for BALs is demonstrated. A fly-eye lens is used to integrate the filaments and homogenize the laser beam. The speckle contrast is consistent with theoretical calculation, which proves the spatial incoherence of filaments. A light pipe is used to introduce an optical path difference between light with different incident angles, enabling more incoherent beamlets. These beamlets are then combined at different illuminating angles by a double-sided fly-eye lens and focusing lens. As a result, the subjective speckle contrast is reduced from 95.94% to 19.13% at 1.2 A while maintaining a high luminous efficiency of 77.8%. This work provides important design principles for laser display systems.

Accession Number: WOS:001182059900001

ISSN: 2040-8978

eISSN: 2040-8986