在星间半导体激光通信系统中,如何检测发射光束波面的质量是个较难处理的问题,为了较好地解决这一问题,在简单介绍白光横向双剪切干涉仪的基础上,报道了用此干涉仪对近衍射极限半导体激光光束波面的检测,在此基础上推导出计算远场发散度的公式。实验测得近场光束的波高差为0.2λ,通过夫朗和费衍射求得光束的发散度仅为64.8 μrad,这表明光束接近光学衍射极限。同时,表明双剪切干涉仪灵敏度高、实用性好。

In the semiconductor intersatellite communication system, how to test the laser beams′ quality is difficult. In order to solve this problem, a basal principle of the white light lateral double-shearing interferometer is introduced firstly, and then measuring the semiconductor laser beam′s wavefront which is near the diffraction-limited by the interferometer is reported, and the formula of calculating the beam′s divergence is deduced according to the Fraunhofer diffraction. A 0.2λ wavefront error is gained experimentally. Corresponding to the wavefront error, the divergence angle is only 64.8 μrad, which indicates the beam is near the diffraction-limited. The result shows that the interferometer has high precision and wide practicability.