| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an aberration compensation element which is thin in thickness and small in size and can easily be incorporated in a pickup. <P>SOLUTION: A quartz plate 21, a liquid crystal layer 22, a glass plate 23, a liquid crystal layer 24, and a glass plate 25 are laminated in this order to constitute the aberration compensation element, and light is polarized by the quartz plate 21, and spherical aberrations of going and returning laser light are compensated by the liquid crystal layers 22 and 24, and the number of glass plates can be made one smaller than a conventional element because the quartz plate 21 has a function of holding the liquid crystal layer 22, and thus the aberration compensation element can be made thin. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
