Design And Research On Photoelectric Imaging Detection System Based On Atomic Filter

At present,target detection and recognition technologies in complex backgrounds mainly include laser detection,infrared imaging detection,radar detection and composite detection.With the attention of various countries to the near space and the wide use of various near-air hypersonic vehicles,higher requirements have been put forward for common photoelectric detection methods in terms of field of view,detection distance and imaging signal-tonoise ratio.Many scholars have started from traditional detection methods to build new long-distance ground-based or space-based detection systems that can achieve accurate detection and identification.In this thesis,based on spectral imaging and photoelectric detection technology,a photoelectric imaging detection system based on atomic filter is designed by using the characteristic spectrum of metal atoms of target tail flame.It has the characteristics of strong anti-interference,large detection field angle and strong background suppression ability,which greatly improves the imaging signal-to-noise ratio of target detection.The specific work of the thesis is as follows:(1)Literature research and actual spectral measurement of various propellants commonly used in high-speed aircraft are carried out,and it is found that they all have obvious characteristic spectral lines of alkali metal atoms such as Na and K.This thesis proposes a new target detection technology using the characteristic spectrum of aircraft tail flame for imaging.(2)A set of photoelectric imaging detection system based on atomic filter is developed,which extends the traditional atomic filter to filter the laser light source to the field of natural light source filtering and imaging,using the integration of the filter and the imaging lens.The design and the inherent characteristics of ultra-narrowband filtering and high Q value of atomic filters have realized a large field of view and high signal-to-noise ratio imaging detection of aircraft targets.(3)An imaging detection system performance test platform is built,and the imaging detection system based on ordinary filters is used to perform imaging detection on the same target separately with the system developed in this thesis,the final calculation shows that the imaging signal-to-noise ratio of the ordinary filter system is 2.9 dB,the imaging signal-to-noise ratio of the atomic filter imaging detection system is 74.4 dB,and the signal-to-noise ratio is improved by about 25 times,compared with the traditional spectral imaging system.has significant advantages.At the same time,in order to verify the stability of the system and the longest detection distance,the field detection of a high-speed aircraft was carried out under complex external field conditions,and the longest tracking distance of the system was verified by processing the results such as image stretching.In this thesis,a new detection method of photoelectric fusion is used to achieve high signal-to-noise ratio detection of targets in complex backgrounds,which has certain application value in both military and civilian fields.