Research And Application Of InGaAs Shortwave Imaging Technology Under Low Illumination

Short-wave infrared(SWIR)covers a wavelength range of 1?3?m and is in the reflection band of the infrared band.Compared with mid-and long-wave thermal imaging,short-wave infrared can reflect more details of objects and facilitate detection and identification;compared with visible light,short-wave infrared has excellent performance in penetrating clouds,fog,smoke and dust.Because of its unique imaging characteristics,short-wave infrared has a wide range of application prospects in the fields of low light imaging,fire point detection,environmental detection,mineral deposit detection,semiconductor detection,crop detection,biological imaging,etc.Therefore,the research on short-wave infrared imaging technology is of great academic significance and application value.The main research work of this paper includes:A high-sensitivity high-speed large-face-array short-wave infrared imaging prototype was developed based on the newly developed 1280*1024 element In Ga As short-wave infrared detector from the Shanghai Institute of Technology Physics,Chinese Academy of Sciences,which realized 30 Hz and high-sensitivity imaging.This paper analyzes the block blind element characteristics in the detector surface array and designs a fast marching blind element compensation algorithm;it studies the relationship between the imaging quality and the operating temperature of the detector at high gain of the In Ga As short-wave infrared detector and designs a closed-loop digital temperature control module based on the integrated semiconductor thermoelectric cooler inside the detector to realize the accurate control of the operating temperature of the detector.In addition,this paper also carries out the short-wave infrared two-grade gain comparison imaging experiments based on In Ga As detector,fog imaging comparison experiments and biological imaging experiments,and obtains good imaging results.For the characteristics of short-wave infrared images under low illumination,a lowillumination short-wave infrared image enhancement algorithm is designed in this paper.Based on the multi-scale Gaussian difference detail enhancement method to improve the details of short-wave infrared images in low light,the sparse expression algorithm to realize the noise reduction of the images,and finally the adaptive gray-scale mapping algorithm to improve the dynamic range and contrast of the images.The experimental results show that the algorithm of this paper effectively improves the imaging effect of short-wave infrared under low illumination.In this paper,we conducted experiments on bio-fluorescence microscopy imaging under low illumination and designed a multi-focus fusion algorithm based on gradient domain guided filtering to achieve global imaging of bio-fluorescent tissue under low illumination microscopy conditions.In this paper,we designed a low-illumination short-wave infrared illuminance meter with a wavelength coverage of 0.9?1.7 ?m,a measurement accuracy of 10^-5W/m^2,and a measurement range of 10^-5W/m^2?0.1W/m^2;the nighttime shortwave infrared illuminance was measured by this illuminance meter,and the influencing factors of short-wave infrared imaging under low-light conditions were analyzed,and the changes of the moon phase and the climate The influence of moon phase changes and climate conditions on the short-wave infrared imaging is discussed.Accordingly,a short-wave infrared small target detection algorithm based on the signal-to-noise ratio criterion is investigated in this paper,and the results show that the algorithm performs well on the dataset of this paper.