| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical head device capable of performing feedback control to a laser light source more properly than the conventional ones. <P>SOLUTION: The optical head device includes a laser light source emitting a laser beam for reading information from an optical disk, a half mirror separating the laser beam by transmission and reflection, and a monitoring light-receiving element 23 for detecting the laser beam separated by the half mirror from the laser beam before reaching the optical disk, from the front for feedback control of the laser light source. The monitoring light-receiving element 23 includes a light-receiving part and a translucent protective layer 23b for protecting a part immediately above the light-receiving part and the periphery thereof. The optical head device further includes a wall 11e which includes a hole 11f for laser beam passing the laser beam separated by the half mirror from the laser beam before reaching the optical disk to the light-receiving part and shields the front side of the monitoring light-receiving element 23 at a part other than the hole 11f for laser beam. <P>COPYRIGHT: (C)2009,JPO&INPIT |
