Abstract:In recent years, research on detection of space weak moving point targets in infrared image sequences under complex background has attracted much attention. This is of most significance to space surveillance systems, early warning systems and missile tracking systems. For various reasons, the detection, tracking and recognition of space-based dim point targets still face many challenges. Both instrument jitter and platform motion may cause the target positioning to deviate. Because of observation distance and space-based imaging environment, targets may be often submerged in background noise or other kinds of noise. Therefore, how to detect and identify moving targets quickly and accurately in low SNR environment and meet the indexes of detection rate and false alarm rate is the problem to be solved urgently in related fields. The research in related fields at home and abroad in recent years is classified and summarized so as to seek for new exploration and discovery on this basis.

Abstract:Combining with the X-ray diffraction technique and the layer-by-layer chemical etch method for peeling damage layers, the depth of the damage layer in InSb crystal introduced by cutting, lapping and polishing was analyzed quantitatively. The structures and causes of damage layers were discussed. The research result showed that cutting was the major process for introducing damage layer on the surface of InSb wafers. The depth of the damage layer introduced by cutting was up to 16 microns. The depth of the damage layer introduced by double-face lapping was about 12 microns. The depth of the damage layer introduced by mechanical-chemical polishing obviously decreased. It was about 2 microns.

Abstract:InSb-based high operation temperature InAlSb infrared detectors are the development direction of a new generation of infrared detectors. The study of surface oxide layers of detector substrates is the basis of the direction. Spectroscopic Ellipsometry (SE) and X-ray Photoelectron Spectroscopy (XPS) are used to analyze the surface oxide layers of the detector substrates grown by the existing processing. By selecting better corrosion liquid from common corrosion liquid, adjusting its ratio and adding inorganic acid, better surface oxidation treatment liquid is obtained. The stability of the surface oxide layer after treatment is compared and the variation of the main components is analyzed. Finally, the substrates which meet the parameters of surface oxide layers for Epi-ready InSb wafers are obtained. This work lays the foundation for subsequent study of high operation temperature detection components.

Abstract:The infrared radiation characteristics of exhaust plume from a certain type of jet engine were measured by using mid-wave and long wave infrared thermal imagers. The radiation intensity of the exhaust plume in mid-wave and long wave bands was obtained. The result showed that both mid-wave and long wave exhaust plume observed from aircraft tail exhibited symmetrical distribution. The greatest radiation intensity and area of the former were 4.6 and 2.1 times as those of the latter respectively. The greatest radiation intensity, plume length and area of mid-wave infrared plume observed from the side of aircraft were 2.2, 3.8 and 5.7 times as those of long wave infrared plume respectively. The advantages of the former were more obvious. In addition, because of the influence of high temperature heating of plume, the temperature of the air around plume rises significantly. Its radiation intensity was higher than that of other background. The measurement results obtained were of referential value to the simulation and calculation of infrared radiation characteristics of aircraft plume.

Abstract:To solve the problem that traditional contact electric parameter fault detection methods are difficult to meet the maintenance requirement of increasingly complex electronic equipment, a temperature rising multi-feature method based on infrared thermography which can improve noncontact electrionic equipment abnormality detection is proposed. Firstly, on the basis of infrared and optical heterologous registration, the accurate position of each element in an electronic equipment is obtained. Then, the mean value curves of temperature rising in the central areas of each standard element and each element to be detected are obtained on the basis of the infrared images observed. After the curves are divided into multiple subsections, the temperature rising statistical vectors are extracted precisely. Secondly, the difference between the temperature rising statistical vector to be detected and the standard temperature rising statistical vector is calculated and normalized so as to construct the temperature rising multi-feature vector. Finally, according to the vector, the whole situation awareness of thermal abnormality of the equipment to be detected is implemented by segmental judgment and abnormal quantification. Compared with the traditional thermal abnormality detection method, the temperature rising multi-feature vector constructed can more precisely and robustly describe the variation of temperature rising. The experimental result shows that this method has the advantages of high accuracy and good real-time performance. It lays a foundation for the subsequent intelligent reasoning of electric circuit fault.

Abstract:The emission layer of β-FeSi2(n)/c-Si(p) solar cell was simulated by AFORS-HET software in gradient-doping and the influence of gradient doping and uniform doping on the conversion efficiency of cells for the same total amount of doping in emission areas was studied. For gradient doping, the influences of emission energy band, emission concentration difference and layer number in emission areas on the conversion efficiency of cells were discussed respectively. The experimental results showed that the use of gradient doping in emission areas could significantly improve the conversion efficiency of cells. With the increase of concentration ratio of each layer in emission areas, the conversion efficiency of cells increased first and then remained unchanged; with the increase of layer number in emission areas, the conversion efficiency increased first and then remained unchanged too; and with the increase of thickness of emission areas, the conversion efficiency decreased gradually. The total increase amount of conversion efficiency of gradient-doped cells was far greater than the total decrease amount of conversion efficiency caused by over thick emission areas.

Abstract:On the basis of the data from Landsat TM and OLI/TIRS, the Land Surface Temperature (LST) in Hohhot metropolitan area is retrieved. Compared with the MODIS LST products, the retrieved LST shows its good accuracy with an average relative error of 5% and a Root Mean Square Error (RMSE) of 1.53 ℃ (R=0.88, e=5%). The research result shows that the LST values of different types of Land Use/Land Cover (LULC) are different. The highest temperature appears in the building land and the lowest temperature appears in the vegetation and water coverage areas. LST is associated positively with the distribution of building land, bare land and semi bare land and is associated negatively with the distribution of vegetation. The building land and bare land have great influences on LST while the semi bare land and vegetation have more stable influences on LST.

Abstract:Near infrared filters and middle infrared band-pass filters have their important applications in aerospace, meteorology, remote sensing and other fields. An infrared filter is a device which can transmit infrared radiation and cut off the light at other wavelengths. The peak transmittance is its main performance index. For a band-pass filter, its important performance indexes include the peak transmittance and the half width of the passband. These performance indexes are most dependent on the film structures and specific design of the optical films for infrared filters. Both kinds of filters and their practical applications are presented.