| 摘要 |
PURPOSE:To improve the overall efficiency of transmission and reception by disposing incident light and an optical plates of which both surfaces are optically polished to have the max. product of the reflectance of S-polarized light and the transmittance of P-polarized light. CONSTITUTION:Laser light 2, which is linearly polarized light, is outputted from a laser device 1. A case in which the light 2 is S-polarized light is explained here: The light 2 is reflected by an optical plate 3, is converted to circularly polarized light by a 1/4 wavelength plate 4, and is transmitted toward an object body 5. The plate 3 which is produced by polishing optically both surfaces of a plate made of an optical material having high transmittance for the wavelength of the light 2 is used. The light reflected of a target object 5 passes again through the plate 4 whereby said light is converted to P-polarized light. This time the P-polarized light transmits through the plate 3 and is made incident to a detector 6, by which said light is detected. |
