| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polarizing beam splitter whose film constitution is managed simple and whose manufacturing is ficilitated by forming multilayer films so as to satisfy a specific condition concerning the relation of the phase difference between the P-wave and the S-wave of a transmitted light. SOLUTION: When δ is defined as the phase difference between the P-wave and the S-wave transmitted through a polarizing beam splitter, multilayer films satisfying nπ+(π/4)<δ<=nπ+(π/2) are formed. When the incident side medium of the polarizing beam splitter is air whose reflectivity is 1, a substrate is niobium acid lithium whose reflectivity is 2.24 and a light beam whose wavelength λis 690nm as a target characteristic is made incident on this polarizing beam splitter at an incident angle of 45 degrees, the reflectivity Rs of an S-polarized light is made to be the order of 80% and the reflectivity Rp of a P-polarized light is made to be 0%. The polarizing beam splitter like this is realized by alternately laminating SiO2 as a low reflectivity material whose reflectivity is 1.46 and TiO2 as a high reflectivity material whose reflectivity is 2.25 on the substrate (whose reflectivity is 2.24) made of niobium acid lithium with prescribed thicknesses. |
