Thermal-structural-Optical Integrated Analysisand Research Of Airborne Camera Aspheric Optical System

Airborne cameras can efficiently obtain ground information and are widely used in many fields.Due to its many design variables,aspheric optical components can meet the design requirements of complex optical systems.The combination of airborne camera and aspherical optical system has become one of the important research directions.During the airborne camera's working in the air,the temperature is a key factor affecting its imaging quality.Therefore,it is of great significance to study the effect of temperature on the imaging quality of the aspheric optical system of the airborne camera using the thermal-structuraloptical integrated analysis method.In view of the gradient refractive index caused by the formation of internal temperature gradients during the operation of the airborne camera,a gradient refractive index coefficient fitting method is introduced.The transient thermal analysis of the airborne camera is performed to derive the node displacement and temperature data of the lens in the analysis results The least square method was used to compile and solve the gradient index coefficient fitting program,and the gradient index optical system model was established.The results show that as the working time of the onboard camera is extended,the gradient index coefficient decreases and the imaging quality improves.The homogeneous coordinate transformation matrix is used to derive the rigid body separation matrix,and the steady-state thermal analysis result node data is imported to solve the displacement and separation of each lens rigid body of the aspheric optical system.Taking the Fringe Zernike polynomial as the basis function,the optical-mechanical thermal integration analysis method is used to solve the surface shape distortion of each lens under different temperature conditions,and the thermoelastic deformation optical system model is established.The results show that the temperature increase and decrease will reduce the optical system imaging Quality,where the camera is more sensitive to high temperature environments.The thermoelastic deformation caused by the temperature gradient at different points in the working process is solved,and compared with the gradient refractive index caused by the imaging quality.The results show that the thermoelastic deformation caused by temperature has a greater impact on the imaging quality of the optical system.The thermal control design requirements for airborne cameras are promoted.The thermal control outer cylinder design and thermal insulation component design are introduced,which provides the design direction and ideas for its thermal design.Carry out high and low temperature experiments on the airborne camera,and evaluate the imaging quality of the images collected in different temperature environments.The experimental results show that the temperature increase or decrease will affect the image quality of the airborne camera,and the airborne camera is more sensitive to the high temperature environment.To verify the effectiveness of the thermal-structural-optical integrated analysis method.