When a Light beam pass through a optical device,a way to reduce the reflective loses from two light pass surfaces of the device is to cut those two light pass surfaces in Brewster angle and the two surfaces are always parallel to each other.
当光通过一个光学器件时 ,一种减少两通光面反射损耗的方法 ,是将此两通光面切割成所谓的布儒斯特角且相互平行。