| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that it is difficult to downsize an optical reproducing apparatus which reproduces an optical disk having a single or a plurality of recording layers, and uses an optical head which varies light-use efficiency by inserting and removing an intensity filter to/from an optical path, and that it takes long time to change the intensity filter. <P>SOLUTION: The light-use efficiency is varied by electrically turning on and off a transmission variable means to reduce the switching time, thereby obtaining the highly reliable and compact optical recording/reproducing appliance without any mechanism. <P>COPYRIGHT: (C)2009,JPO&INPIT |
