The method of wave-front aberration for correcting astigmatism in semiconductor laser beams

In this paper,the method of wave front aberration is employed to study the transformation properties of semiconductor laser beams.Using the optical system composed of a cylinder lens and a collimation lens is a useful method to correct the astigmatism of the semiconductor laser beam.This paper presents the exact design formulas of cylinder lens,which respectively correspond to two arrangements of the cylinder lens placed in front of or behind the object lens.And this paper points out if the waist position of semiconductor laser beam meets the condition of x2os>-fLf'L,the cylinder lens should be placed in front of the object lens,reversely the cylinder lens should be placed behind the object lens and simultaneously the position of the cylinder lens should meet the condition of x'C>-fLf'L.Finally,the optimun position of the cylinder lens in the correction astigmatism system for the semiconductor laser beam is derived.