| 摘要 |
PROBLEM TO BE SOLVED: To realize an autofocusing device capable of executing autofocusing operation with high accuracy even when the depth of focus is made deep without largely influencing various kinds of specimens by the characteristic of a lens optical system. SOLUTION: In this device 1, specified voltage V is impressed on a focusing objective lens driving coil 25 based on the returned light of a laser beam irradiating the focusing reference area R2 of the specimen R, and a focusing objective lens 21 is focused on the area R2. When an actuator 50 integrally drives the coil 25, the lens 21 and an objective lens for observing a specimen 11, a driving control part 60 performs servo control so that the impressed voltage V on the coil 25 may coincide with reference voltage VO previously set, and the lens 11 is focused on the observing area R1 of the specimen R. |
