| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a deformable mirror device capable of effectively correcting a spherical aberration caused by a difference in the thickness of a cover layer covering an optical disk recording layer. <P>SOLUTION: For example, a concentric circular projected part is formed to give a strength distribution pattern 2a to a flexible member 2 having a reflection film (mirror surface) 3 formed therein. An attraction force generated by an electrostatic force is generated on an upper electrode 8 and a lower electrode 9 according to voltage application from a drive circuit 10, and a first space 15 expands as much as a second space 7 shrinks to deform the mirror surface into a convex shape. The shape of the mirror surface is deformed into a desired shape capable of correcting a spherical aberration by means of the formation pattern of the strength distribution pattern 2a on the flexible member 2. A single drive actuator (drive circuit 10) suffices for deforming the mirror surface. The shape of the mirror face can be deformed into a prescribed shape stepwise depending on the formation pattern of the strength distribution pattern 2a, and spherical abrasion correction can effectively be performed to recording layers, for example, three or more layers. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
