The High Precision Collimation Technology Of Optical Axis And Pupil

In optical systems, the laser beam can not reach the destined place wheninfluenced by distortion of the mirror support frames caused by gravity and thechanging of temperature, shock of the environment, excursion of the output ofoscillator, motion between different optical systems and other disturbance. As therapidly development of the laser technology, there are more optic system with largequantity of optical device and element. It will cost lots of time and resources in opticpath adjustment and excursion correction by hand and the precision does not satisfyapplication. So the automatic collimation system is extracted to solve the problem andit is the vital part of large laser devices.In applications, some collimation systems will not work for the complex shape ofthe laser beam, bad imaging quality and dynamically changing of intensity. On thebase of former researches, a new optic axis and pupil collimation scheme based onimage processing is designed. The main contents include:Firstly, the related technologies of collimation system in some laser applicationfield are investigated. Main principle, precision, utility scope and other information ofthe collimation system in different optic systems are introduced. Then the basicprinciple and composition of an automatic collimation system are introduced and thekey problems of the research are come out by analyze real condition.Secondly, some relative contents such as image preprocessing and Fouriertransformation are introduced what are used in the collimation system. The algorithmsin detection of target motion that will be used in pupil motion detection are introducedin details. Then some performances such as precision and robust of the algorithms aretested using the real pupil images. Especially, phase-correlation algorithm is analyzedand tested in detail. Through comparing the algorithms, phase-correlation algorithm isselected for pupil motion detection.Finally, the experiment system is built up for test the new collimation scheme. The contents include set-up of the system, introducing of devices, programming andexperiment result analysis. The feasibility of the scheme is proved. The precision ofoptic axis correction is better than5″and50μm to pupil correction. The speed of thecorrection is about4Hz. The precision is lower than designed value and the mainreason is the limitation of the correction device.There are more woks should be done, especially in the improvement of the speedof detection algorithm and the control parameter in the experiment.