| 摘要 |
<P>PROBLEM TO BE SOLVED: To miniaturize a device using an optical recording medium. <P>SOLUTION: Ahead of a laser element 10 for a CD, a penta prism 62 is provided for reflecting a CD laser beam twice and rotating its path by 90 degrees. Moreover, the combination of a second PBS (polarizing beam splitter) layer to be provided at the penta prism 62 with a quarter-wave plate 22 function as an optical isolator. Thereby, a PBS 18 formed independently heretofore is eliminated. A space necessary for the optical path of the CD laser beam is reduced by reflecting the path of the CD laser beam twice. <P>COPYRIGHT: (C)2003,JPO |
