| 摘要 |
PROBLEM TO BE SOLVED: To provide an autofocus mechanism applicable to an objective lens with small numerical aperture and usable in the scanning of an object. SOLUTION: This autofocus mechanism 40 is operated together with a microscope having a main optical path, an objective lens, an object surface, an image surface and a means for changing the distance between the objective lens and the object surface to focus the image of the object, and it preferably has a pattern imaging system, an image detector 70, and a pattern focus analyzer 72. The pattern imaging system images at least one pattern on the object surface, the image of the pattern and the image of the object are then composed and reflected, and the reflected image reaches an image surface along the main optical path. The reflected image is detected by the image detector 70, the pattern focus analyzer 72 measures the visibility of the pattern by analyzing the output of the image detector. The pattern focus analyzer 72 can also instruct the device for changing the distance between the lens and the object surface to move in order to focus the image. |
