Design Of Airborne Small Dual-band Integrated Optoelectronic Aiming Optical System

The single photoelectric payload carried by UAV can no longer meet the task requirements of searching,capturing and identifying targets in the complex and changeable environment.In order to improve the application performance of UAV,the integration of various photoelectric payloads is particularly important.In this dissertation,under the requirements of the integration of various photoelectric payloads,aiming at the problems of central obstruction,low energy,and difficulty in assembly in the reflective front optical path used in traditional multi-band co-aperture optical imaging systems,a dual-band co-aperture optical system with refraction imaging in front optical path was designed to realize the dual-band integration of airborne photoelectric aiming optical imaging system.At the same time,it also achieves high resolution imaging of the same target,thus improving the application efficiency of UAV in complex environment.The initial focal length of the ideal lens group of the zoom optical system was calculated by using the two-component zoom theory,and the appropriate optical materials were selected to optimize the dual-band co-aperture optical imaging system,and the imaging quality of the optical system was evaluated by using two image quality evaluation methods,namely,geometric optics and diffraction theory.According to the YNI contribution value,the influence of the reflected light on the imaging quality of the mid-wave infrared system was analyzed by using the backward tracing image of the reflected light from the focal plane of the lens surface of the optical system.Under the condition that the visibility is greater than 10km and the relative humidity is less than 60%,the detection distance of the visible light imaging system was calculated theoretically.Based on the MRTD model(minimum resolvable temperature difference)and Johnson criterion,the operating distance of the mid-wave infrared imaging system was analyzed.Finally,according to Rayleigh criterion,at a certain detection height,corresponding to different flight speed and exposure time,the forward image motion compensation residual analysis of integrated photoelectric aiming optical imaging system was carried out by using the electronic image motion compensation method.The design results show that the optical imaging system works in the band of 0.38～0.76μm and achieves a 5× continuous zoom of 36～180mm,when works in the band of 3～5μm,it can realize three field of view transformation with F/#of 4,and the ratio of three field of view to three levels of focal length is 3.In the working environment of-40℃～+60℃,the optical imaging system can meet the imaging quality and design requirements after optical passive non-thermal treatment.