| 摘要 |
PURPOSE:To make alignment of an element to be aligned accurately and easily even if the element is minute such as a semiconductor laser by a method wherein a polarization beam splitter is obliquely arranged to a linear polarization laser by a few degrees. CONSTITUTION:Most of polarization beams L1 transmitting a polarization beam spritter 16 once turned by 45 deg. by a 1/4 wavelength sheet 17, (20) reaches an element 15 to be aligned while the light L2 reflected by the element 15 is further turned by 45+ or - by the 1/4 wavelength sheet 17 i.e. to be turned at the main polarization beams L1 by 90 deg. so that the light L2 may be reflected by the polarization beam splitter 16 to be entered into a detector 19 for detection. The detector 19 can detect both the reflected light L2 from the element 15 to be aligned and the reflected polarization beams l2 from a reflector 18 but the reflected light L2 from the element 15 becomes faint beams taking a bright spot shape compared with the reflected polarization beams l2 from the reflector 18 due to small size of said element 15 itself. In such a constitution, the element 15 can be aligned by adjusting itself so that the beam spot may be focussed on the central point of reflected light from the reflector 18. |
