| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical retardation plate excellent in the incident angle dependency of a phase difference and an optical head device using the phase difference plate. <P>SOLUTION: This optical retardation plate is composed of two transparent substrates 101, 102 which are opposed to each other, and a liquid crystal layer 107 held between them. Horizontal orientation processing is applied to the plane of the transparent substrate where the liquid crystal layer is brought into contact so that an angle between the orientation processing direction 105 and the direction 106 of respective substrates becomes 0°. This optical retardation plate is excellent in the incident angle dependency of a phase difference, when it is used for an optical head device, since the phase difference of light passed through the optical retardation plate becomes concentric circular distribution in a beam plane, a favorable reproduction property and a favorable recording property can be obtained. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
