Research On Space Camera Image Degradation Induced By Micro-vibration

With the improvement of the space camera detection ability, the focus of opticalsystem has become longer and longer and the camera’s aperture and the size has beenbigger and bigger. At this point, the influence of the optical system image qualityinduced by micro-vibration is more serious than ever. It is necessary to study theinfluence of micro-vibration on the optical system imaging quality to improve theimaging quality of space cameras.Aiming at space micro-vibration disturbances affect on optical system imagingquality degradation, this paper, using the integrated model method, completed theprocesses from the micro-vibration interference sources to the rigid bodydisplacement of the optical element and from optical element rigid bodydisplacement to image quality degradation. Taking a space camera as the researchobject, firstly, a unit displacement load was applied for the optical system, fromstatic analysis getting the conclusion that the biggest influence of micro-vibrationload direction was along the optical axis. Secondly, considering the space cameradetector CCD integral time, dynamic analysis was undertaken the optical systemwith micro-vibration along the optical axis. The results show that both the CCDexposure starting moment and integral length have effects on image quality. Finally,in order to define how degree the optical element micro-vibration influence on theoptical system imaging quality, sensitivity analysis has been finished, results showthat the tilting of primary mirror highly sensitive to the optical system imagingquality.Through a series of analysis to the space camera, results show that theintegrated model method is the most efficient method to analyze the influence ofmicro-vibration on the optical system imaging quality. Through dynamic opticalsystem imaging evaluation and sensitivity analysis of structural response coefficient,the comprehensive evaluation can be implemented in the design phase of the optical imaging system. It provides a reference for optical system design, structureoptimization and vibration isolation.