Research On The Measurement Method Of Multi-axis Consistency For Non-imaging Optical Systems

In recent years,with the development of optical technology and the continuous growth of application requirements,multi-optical-axis photoelectric systems that integrate visible light,infrared,and laser equipment have been widely used.Their optical subsystem integrates different kinds of photoelectric sensors,whose spectrum ranges from visible to infrared,and their layout in the equipment is more complex.Optical axis consistency is the key to subsystems coordination and an important index to ensure the normal operation of the equipment,so it’s important to be detected.Non imaging optical systems,such as space laser communication system,lidar system,laser ranging system and laser tracking system,often use non imaging optoelectronic devices which are difficult to provide visual feedback.So it is difficult to extract the optical axis,which greatly increases the difficulty of multi axis consistency detection.On the basis of the analysis and comparison of existing optical axis consistency detection methods,this paper studied the multi-axis consistency detection of non imaging optical system,and designed an optoelectronic testing system for multi-axis consistency detection of non imaging optical system.First of all,according to the actual detection requirements of a laser ranging system,the overall technical solution of the multi-axis consistency detection system suitable for this type of system was proposed;The active illumination imaging method was used to solve the problem that the optical axis of the nonimaging receiving subsystem extracted hardly: Based on the research on the principle of splitimage fixed focus,a split-image focus measurement unit for non-imaging detector fixation and adjustment was designed,which converts the traditional axial defocusing into lateral alignment measurement,and further improve the optical fixed focus accuracy of the nonimaging detection branch system.Secondly,the overall optical mechanical structure of the multi-axis consistency detection system was designed,and the assembly and testing process of system was also completed;The stray light was analyzed by Fred software,and the stray light was effectively suppressed by optimizing the structure parameters of the lens hood.Finally,the system performance indicators were tested and analyzed.The test results show that the consistency detection error between the receiving axis and the emitting axis is0.015 mrad,and the consistency detection error between the viewing axis and the receiving or emitting axis is 0.0178 mrad,which are less than the index requirement of 0.02 mrad.