| For the progress of science and enhancement of machining ability, space optics has beingdeveloped greatly. More and more telescopes and space cameras were launched into space toserve the human being. In order to test those telescopes, large aperture and long focal lengthcollimator has made an extraordinary progress as telescopes are developing. As the mostimportant property of collimator, the test of parallax must be developed.At present, the method often use to measure the parallax of Large-aperture collimator ispentaprism method, reading existed artificial error, a kind of automatic inspection system forparallax of large-aperture collimator been put forward based on circular matching. Using therail which is precision to make the errors more smaller which is bring by the move of thecamera, with the high-definition camera, the image of the reticle that got will be more clear,so the error also be smaller, In order to make the system can adapt to variety of parallel, usingheight-adjustable head to adopt the height of the collimator, and using360°rotaing head toadapt to the angle of it. When got the image, the center of the circle was found through OTSU,filtering, edge detection, circular catching, data fusion based on support, parallax was givenfinally throw calculate.The move of the rail can be a narrow range because the system is automatic. We can getmore pictures of the reticle easily, so the curve of the parallax can give out, this will make thecalibration of collimator convenient.In the process of the testing for Parallax of Large-aperture Collimator, there are someerrors due to straightness of rail, axis do not coincide, effective pixels of camera and the resultof the digital image processing. Automatic inspection system for parallax was proved bydevice tests that the test results are accurate and has good repeatability. |
