| 摘要 |
<P>PROBLEM TO BE SOLVED: To avoid the occurrence of deformation of an organic film, on which a diffraction grating or the like is formed, by specifically limiting the physical characteristics of adhesive used for the adhesive layers of a polarized beam splitting element, to reduce the stresses on the adhesive layers of the organic film caused by external force received by an optical element, such as vibrational or environmental changes under high temperature and high humidity, and to prevent occurrence of peeling. <P>SOLUTION: A ruggedness shape diffraction grating 2 is formed on the top surface of an organic double refractive film 5. The film 5 is adhered on top of an optically transparent bottom substrate 3 by a bottom adhesive layer 4, and an optically transparent top substrate 7 is made to adhere to the side of the diffraction grating 2 by a top adhesive layer 6. An adhesive, having the same material, is used for the top and the bottom adhesive layers 4 and 6 and the physical characteristics of the adhesive satisfy at least one of the following conditions, i.e., viscosity <3,000mPaXs, Shore hardness <D85 or the rate of water absorption <2%. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
