| 摘要 |
PROBLEM TO BE SOLVED: To provide a polarization separation element which can simplify the optical system and reduce the size and the cost. SOLUTION: The polarization separation element 30 is produced by forming an organic film 32 having optical anisotropy on a borosilicate crown optical glass (BK7) substrate 31 which is an optically isotropic substrate, forming a periodical rugged structure, namely a grating 33, on the surface of the organic film 32, filling the recesses of the grating 33 with a material which is optically transparent and has the refractive index equal to the refractive index in the ordinary ray direction of the optically anisotropic film or equal to the refractive index in the extraordinary ray direction, and further forming a quarter wave plate 34 in the light exiting side of the grating 33. An optical element 40 which can vary the diverging angle of laser light from a semiconductor laser 10 is formed integratedly with the polarization separation element 30. |
