In order to implement the function of a helmet display system, a small size and light weight color micro organic light emitting display (OLED) is used as image source in the simulator, which has higher brightness and resolution. The optical system is composed by double convex lens and translucent plane mirror, in which can satisfy the needs of helmet display by perspective and collimation display. The measuring equipment contains double cameras and double infrared radiators, meanwhile the helmet position is obtained by software collecting and processing, which can gain big position measurement range and small helmet added weight. The application results show that the simulator has good versatility and the functions and technical indexes reach the design requirements. The design can provide references for vehicle-mounted, ship-based and airborne helmet display system simulators.

Optical thin film polarization splitting prism is one of the important parts for modern photoelectric display, test and information transmission systems. However, conventional optical thin film polarization splitting prism has some technical difficulties, such as poor chemical stability of substrate, narrow polarization splitting bandwidth and small application angle. By studying the principle of Brewster angular polarization splitting and the polarization separation effect of interference cut-off filter, the polarization splitting bandwidth of polarization splitting prism is extended by combining two design methods. The polarizing beam splitters of p-polarized light 0.44～0.64 μm, Tave≥95%, Rave≤5%, and s-polarized light 0.44～0.64 μm, Tave≤5%, Rave≥95% on the BK7 substrate of Schott optical glass with good chemical stability are prepared. This kind of optical thin film can be used to design and optimize wide-band, wide-angle and high polarization extinction ratio polarization splitting prisms on different glass substrates. It provides a new theoretical basis and preparation scheme for the design and preparation of polarization splitting prisms.

The design method of long-wave athermal lens is discussed. The new chalcogenide glass material is adopted in the design of optical system. The characteristics and applications of the chalcogenide glass are introduced. The design method of athermal optical lens is analyzed. And the long-wave infrared athermal lens with chalcogenide glass is designed on the basis of technical requirements. By matching the chalcogenide glass with other infrared materials reasonably, through system optimized design, a better imaging effect is obtained in a wide temperature range.

The high efficient fabrication craft research on the low curvature lens has been done through the numerical control milling and grinding machine SPM-60 and the numerical control polishing machine SPS-60 made by LOH company in Germany. The obvious craft factors influencing on component surface during polishing process have been found through the orthorhombic experiment. The best craft parameters have been found by single factor experiment, such as 700 r/min rotatory speed of polishing tool, 0.16 bar pressure and 500 s polishing time. Depending on the surface shape of the lens after milling and grinding and fine grinding, the proper polishing order is done to realize the high efficient process craft of the low curvature lens.

Mid-infrared laser sources in laser countermeasure systems at 3~5 μm are introduced, including solid optical parametric oscillation lasers, doped fiber lasers, photonic crystal fiber lasers and quantum cascade lasers. Based on laser output, weight and beam quality, the characteristics of these lasers are analyzed. And the key technologies used in airborne platform to be resolved are pointed out.

A high power diode-pumped Tm:YLF laser operating at 1.89 μm with FWHM line width less than 0.1 nm is introduced. The YAG Fabry-Perot etalons of 0.05 mm is inserted to polarize at Brewster angle in laser cavity, and 1.89 μm horizontal polarized light is obtained. Two Fabry-Perot etalons with 0.05 mm and 0.3 mm YAG are inserted successively for spectral narrowing and laser stabilization. Under incident pump power of 137 W, 46 W continuous output power with 1 889.3 nm output wavelength and 45.1% slope efficiency is achieved. The laser wavelength shift of only 0.12 nm with the incident pump power from 20 W to 137 W is observed. The beam quality factors at output power of 15 W and 30 W are 1.7 and 2.2 respectively.

The efficiency of high-energy laser atmospheric propagation is closely related to atmospheric factors. The gas molecules and aerosols in the atmosphere cause the attenuation effect, turbulence effect and thermal blooming effect, and the laser power density at the target is reduced. Due to the complexity of the actual atmospheric environment, the coupling of various atmospheric factors constrains the research of high-energy laser propagation mechanism. There are many uncertain factors in the testing of mathematical physical models. The simulation of the actual atmospheric environment using the laser atmospheric propagation channel simulator controlled by atmospheric factors is extremely important for the study of high-energy laser atmospheric propagation. It can not only quantitatively explore the influence mechanism of atmospheric factors on laser atmospheric propagation, and verify the simulation results of physical models. Accuracy and improved model reliability also provide basic data for the evaluation of laser propagation effects. The design of an experimental device that can simultaneously simulate the laser propagation effects of turbulence, attenuation and thermal blooming is introduced.

To solve the degradation of color images caused by low illumination condition, a novel algorithm to improve the visibility of low illumination images is proposed. At first, the operation based on logarithmic image processing (LIP) model is adopted to regulate the luminance component calculated from the color image in YUV color space so that the brightness and contrast of low level gray regions of the image can be increased accordingly. And then, the contrast limited adaptive histogram equalization (CLAHE) with suitable parameters is introduced to modify the luminance component to improve the quality of image enhancement further. At last, a linear color restoration process based on the luminance gain is used to determine color values of the enhanced image. Experimental results show that the proposed algorithm is more effective and practicable, and the enhanced image can achieve an excellent global visual effect with clear details and natural colors, while avoiding excessive enhancement, noise enlargement and so on.

Compressive sensing reconstruction is a new theory of signal acquisition and processing, which breaks through the traditional sampling theorem’s requirements on Nyquist sampling frequency and the original signal can be reconstructed for sampling times far less than the requirements of sampling theorem. At first, three methods of constructing random matrix are introduced. And then, different kinds of compressive sensing algorithms are introduced, and two of them are simulated and compared. At last, based on this, the influence of the algorithm on image reconstruction quality under different noise levels of measurement matrix is simulated. Through simulation analysis, total variation augmented lagrangian 3 (TVAL3) algorithm is outstanding in image reconstruction time and noise reduction.

The dim and small infrared targets are easily covered for the background edge and strong noise, and the dim and small target detection is always the difficulties of infrared image processing. Based on analyzing the infrared image model, max-median filter algorithm is introduced to inhibit isolated noise point and improve signal to noise rate (SNR) under the condition of no influence on edge sharpness. And the dim and small target is detected at last using variance K-means clustering algorithm. Experimental results show that comparing with traditional filtering and morphologic algorithms, the algorithm has simple calculation, which can effectively get the dim and small target．

Because of the advantages of powerful error detection, high reliability, high efficiency and transparent transmission, high level data link control (HDLC) protocol is widely used in the field of medium and high speed synchronous half-duplex and full-duplex communication. In special occasions such as aviation and aerospace, due to higher requirements of transmission correctness and reliability, HDLC protocol always needs to be improved. A HDLC interface design using special data frame which completed single channel half-duplex data communication is described. Using STM32F103 microprocessor and differential driver and receive pair chips, this design achieves parsing and generation of HDLC data using special frame by the way of software programming. The test results show that the communication interface design is reasonable, correct and feasible.

The methods of temperature measurement power exponent curve fitting and cubic spline interpolation radiation calibration of an infrared thermal imager are analyzed. The radiation calibration of a typical middle wave (MW) infrared thermal imager is carried out by using a high accuracy temperature control surface source blackbody to obtain the correct relationship between the blackbody temperature and the output voltage signal. The power exponent the least square fitting and cubic spline interpolation are performed on the calibration experimental data, and the temperature measurement error of the two methods are compared. The result shows that the temperature measurement errors of the two fitting methods decrease gradually with increasing of fixed punctuations. The power exponent least square method can obtain higher temperature measurement accuracy when three temperature points are used in the range of temperature measurement. In the range of temperature measurement, the 3-points punctuation with uniform distribution of temperature interval can obtain higher accuracy temperature measurement than that of uniform distribution of gray interval. The temperature measurement accuracy of this calibration method can reach 0.1 K, which is an ideal, fast and accurate temperature measurement method for thermal imager.

For infrared imaging guidance missile, infrared smoke is a kind of jamming method with higher efficiency cost ratio. For realizing effective jamming, the jamming performances of the infrared smoke must meet the requirements. The jamming effectiveness of the infrared smoke is analyzed. The dynamic testing methods for transmittance, extinction coefficient, levitation performance, dispersion and fluidity are analyzed. Some examples are presented, which can provide technical supports for infrared smoke test and evaluation.

To analyze the seasonal camouflage requirements of the coating average emissivity at 8~14 μm waveband and the thickness of phase change material (PCM) layer, with the investigation on solar radiation, the vegetative cover′s temperature and the air temperature in one day, a temperature model of target that display the changing of its radiation temperature in one day of different seasons is built. The thickness of the PCM layer and the coating emissivity are changed to obtain the the target radiation temperature. The camouflage efficiency is calculated with different PCM layer thickness and coating emissivity, taking the camouflage efficiency and actual application into account, when PCM layer’s thickness reaches 1.5 mm, the result is suitable. In this condition, in order to obtain the best camouflage efficiency in the daytime, the coating emissivity should reach 0.5, 0.3, and 0.4 respectively in spring, summer and autumn. To obtain the best camouflage efficiency of the night and whole day, the coating emissivity should reach 0.9, 0.8 and 0.9 respectively.

The problem of the synchronization for discrete uncertain spatiotemporal networks based on sliding mode control is discussed. At first, an effective network sliding mode surface and a network synchronization controller are designed. From this, the stability condition of the sliding surface is derived. Further the stability condition is used to determine the range of adjustment parameters in the sliding surface, and the recognition law of unknown parameters is designed. And then, the unknown parameters in the sliding surface are identified effectively. At last, the spatiotemporal network with the actual electro-optical spatiotemporal chaos model is constructed. And the feasibility of the synchronization scheme and the effectiveness of the controller are verified by simulation. The proposed synchronization technology allows the topology of the network to be arbitrary, and this synchronization scheme does not need to design Lyapunov functions. The network synchronization can be realized by adjusting the parameters in the sliding surface.