In the usual lives, laser beam need either propagation through optical system to interreact with other material or in order to satisfy the parameter require.
Satellite retroreflector is used as laser ranging cooperative target to improve the intensity of reflected beam, which has close relationship with processing parameters of the retroreflector.
Based on the double refraction principle of outgoing beam in the biprism,the displacement method for measuring the small angle of biprism is presented.The error of this method is also discussed.