Optical System Design Of Dual-band Common Aperture Compound Guidance Coordinator

In view of the complexity of the detection environment and the diversity of targets,the single-mode guidance beacon indication optical system is already at a disadvantage.However,dual-mode guidance can better match the existing problems of detection.The main types of existing dual-mode guidance are infrared/radar,radar/television,infrared/ultraviolet,millimeter wave/infrared,infrared dual-band,etc,however,there are few studies on visible/long-wave infrared.Since Infrared imaging has strong penetrating ability and high detection accuracy,but it is easily affected by infrared decoy,smoke screen and stealth.Visible light imaging has high resolution and rich spectral information,but its image anti-interference ability is poor,not only image the target with high resolution when the visibility is good in the daytime,but also detect the target with infrared radiation at night or under low visibility.By analyzing the wide-band achromatic,parfocal theory and MRTD model,An optical system of refracting and reflecting dual-band common aperture compound guidance positioner is designed,which has a working wavelength of 0.486~0.656?m and 7.7~9.5?m,pitch and yaw field of view is-26°~ +26°,focal length 105 mm,F number is 2.Considering that the guidance optical system is affected by the aero-optical effect,the turbulence model is established on the fairing to analyze its deformation,and the maximum deformation variable is brought into the optical system structural parameters for passive athermalization;According to the basic principles of infrared radiation and heat transfer,the heat exchange process of the characteristic target surface was analyzed,and the infrared image was simulated according to the route of "temperature-infrared radiation value-infrared image gray value".Electronic motion compensation method is selected to compensate the motion of the detected target relative to the position indicator system.The design results show that the optical system of dual-band common aperture compound guidance position indicator meets the requirements of various technical indicators.the optical system imaging quality is good,the in-40? ~ +60? temperature range poor heat dissipation,imaging quality close to the diffraction limit.The designed dual-band optical system has the property of parfocal length and the visible/infrared thermal defocusing amount is within the range of focal depth at different temperatures.It satisfies the consistency of compound guidance dual band synchronous detection and target information recognition.