| 摘要 |
PURPOSE:To make the detection of focus easy and to simplify the constitution and assembly of the device, by moving the photoelectric plane near the focus with the lens to be inspected for the light transmitted through an objective plate along the optical axis and detecting the output and displacement of the photoelectric plane for operational processing. CONSTITUTION:The light from a light source 1 via the lens 2 passes through an objective plate 3 having pin holes and the image of it is formed near the photodetecting plane 91 consisting of e.g. CCD through the collimator lens 4 and lens 6 to be inspected. The focus plate 9 supporting the photodetecting plane 91 is finely moved back and forth on the optical axis via the feed mechanism consisting of the thimble 83 and spindle 82 linked with the motor 84. The extent of movement is stored in the memory circuit 12 via an ADD conversion circuit 85, and address circuit 13. Further, the detection signal of the photodetecting plane 91 is stored in the memory 12 via an amplifier 10 and sensitivity adjusting circuit 11, and the position of focus is displayed via the control circuit 16 and a retrieval circuit 14. Thus, the detection of focus is made easy, and the constitution and assembly of the device can be made easy. |
