Abstract:A complete infrared imaging system contains a number of subsystems for processing different information. The processing and reconstruction process for a scanned image is discussed. The characteristics of single-point and two-point correction methods for eliminating fixed pattern noise are analyzed. The improvement effectiveness of an infrared imaging system after a reference blackbody is included in its scanning system is presented. Finally, the image processing and reconstruction process is summarized systematically.

Abstract:As a nondestructive method, optical inspection is the preferred method in several latent fingerprint detection methods. In the face of increasingly complex application scenes, the traditional optical inspection method is often ineffective. However, the polarization imaging detection not only can obtain the intensity and spectral information of a target, but also can obtain the polarization information such as polarization degree and polarization angle etc reflecting the surface details of the target. By use of the advantages of polarization imaging, the research on polarization imaging detection of latent fingerprints based on active polarized light is carried out. The fingerprint image data is obtained and analyzed. The result shows that compared with the common light intensity imaging, the method can obtain higher quality latent fingerprint images. The images are clearer and have more detail information.

Abstract:According to the configuration requirement of an InGaAs shortwave infrared detector, a FPGA-based configuration method for the shortwave infrared detector is proposed. Taking a FPGA as a core processor, the configuration of the shortwave infrared detector is implemented in VHDL language. A RS-232 interface is used to communicate with the host computer, to send and adjust the parameters such as the data output order of the detector online and to send the instruction for switching the Integrate Then Read (ITR) and Integrate While Read (IWR) operation modes of the detector. The practical application shows that the configuration method can make the detector operate well and adjust the operation mode and configuration parameters of the detector flexibly. It meets the practical configuration requirements of the shortwave infrared detector.

Abstract:The absorption characteristics of a grapheme cavity in a one-dimensional periodic structure are studied by using a transfer matrix method. The variation of the absorption frequency and absorption peaks in the waveband from 700 nm to 950 nm is analyzed by changing the size of different media, the incident angle and the electromagnetic wave mode. The result shows that single frequency or two frequency peaks may be produced when the thickness of the defect layer is changed. The variation of the incident angle and electromagnetic wave mode has a greater influence on the values of absorption peaks. The result may provide theoretical basis for the design of near infrared grapheme absorbers.

Abstract:According to the practical requirements of the phase transition temperature close to room temperature, the good infrared transmission adjustment ability and high visible light transmittance of the VO2 layer stacks for smart windows, a high performance smart window layer stack composed of a tungsten-doped VO2 layer and a SiO2 antireflection layer is designed by using a CODE (Coating designer) software. The influence of the thickness of each layer on its infrared transmission adjustment ability and visible light transmittance is studied systematically. The layer stack composed of glass/70 nm tungsten-doped VO2/50 nm SiO2 is found to have the best comprehensive performance. It is prepared by using a large area magnetron sputtering system. The experimental measurement result shows that it has a phase transition temperature of 38.2℃, an infrared transmission adjustment ability of 40.4% and a peak visible light transmittance of 46.3%. In the infrared band of sunlight, it has good incident radiation adjustment effectiveness. Moreover, the preparation method of the layer stack is compatible to the current large area glass coating process. So, it is suitable for industrial production.

Abstract:Although the mechanical joint face plays an important role in the field of structural dynamics, few applications of it are found in the design and analysis of space camera structures. The dynamics of two kinds of bolt joint face models are studied mainly. First, two kinds of sample models are established and their parameters are determined according to the spring-damp joint model and the virtual material model theory. The parameters of the spring-damp joint model are determined by combining theory with practice while the parameters of the virtual material model are determined according to the model theoretical formulas. Then, the sample modality of two kinds of models under the finite element condition is compared and analyzed through finite element calculation. Finally, the advantages and disadvantages of two kinds of model dynamics are compared. The result shows that for the spring-damp joint model, the vibration mode fits well with the actual mode while for the virtual material model, the low order natural frequency value fits well with the actual modality. It provides the basis for the application of joint face dynamics models in the analysis of space camera structures.

Abstract:As a new image acquisition technology, the thermal infrared imaging can avoid the influence of illumination and background color on its image acquisition. Currently, the algorithms which use a thermal infrared sequence for target tracking mostly combine visible light images with thermal infrared images. In view of this limitation, a tracking algorithm based solely on the thermal infrared sequence is proposed. First, the background information and the moving direction of a target in the sequence are modeled by using a modified codebook algorithm. Then, the modeling result is incorporated into the compression tracking algorithm. The information on background, target motion and target characteristics is complemented one another in the tracking process. The experiment shows that the improved algorithm is fast in processing. Because its accuracy is improved greatly, it is adapted to the characteristics of thermal infrared sequences better.

Abstract:When the model of infrared attenuation of water mist is established, the space of water mist is usually treated as a homogeneous whole. However, because of diffusion, the droplet density of water mist can not be kept consistent everywhere. So there is commonly a great deviation between the simulation result and the actual situation. To solve this problem, a new modeling method based on Gaussian diffusion theory and Mie scattering theory is proposed. By dividing the space of water mist into several subspaces and calculating the extinction performance of the water mist in each subspace, the modeling accuracy is improved. At the same time, the infrared radiation attenuation of the water mist in different directions is analyzed according to the simulation result. This research work is of a certain reference value to the making of an effective infrared countermeasure strategy.

Abstract:To improve the reality and validity of the testing result of infrared smoke jamming, a method for testing the jamming effectiveness of infrared smoke for a naval ship based on an infrared imaging seeker simulation equipment is studied. Compared with the measurement equipment such as infrared imagers, this equipment can obtain much more authentic test data. So, it is of practical significance to the testing of the jamming effectiveness of infrared smoke.