| 摘要 |
PROBLEM TO BE SOLVED: To provide a variable shape mirror apparatus capable of accurately correcting a spherical aberration generated at a convergence spot of a laser beam, while being simply structured and compact, by changing the shape of a mirror on which the laser beam is made obliquely incident into an elliptic paraboloid shape.SOLUTION: A variable shape mirror apparatus includes a mirror element portion having a reflecting function, a movable member which comes into contact with the mirror element portion, a driving portion which drives the movable member at right angles to a surface of the mirror element portion, and a case which holds the mirror element portion and driving portion. The mirror element portion has a uniform film thickness and the case has an elliptic opening portion. A surface of the mirror element portion which reflects a laser beam is in contact with the case around the elliptic opening portion of the case, a surface of the mirror element portion which is a region outside a tangent thereof and reflects the laser beam is in contact with the case, and a surface of the driving member which faces the mirror element portion is elliptic. |
