Based on the requirements of double-band detection MIR and LIR wave RC optical system with common aperture is designed. The cold stop match of the detector is achieved to reduce inner stray radiation, system volume and weight with secondary imaging mode. The focal length of the common aperture system is 400 mm. Modulated transfer function (MTF) is 0.45 at 33 lp/mm middle wave IR detector cut-off frequencies. MTF is 0.4 at 20 lp/mm long wave IR detector cut-off frequencies. The system has good performance.

According to the requests of the customers, the optical parameters of the objective on small UAV are calculated at first, and the optical design characteristics of the objective are obtained. And then based on the characteristics, a small refractive objective with 52.5 mm focal length, F/2 relative aperture, 12° field of view and 286 lp/mm Nyquist frequency at visible light waveband on UAV is designed. CMOS devices with 1.75 μm single pixel are chosen as receiving devices and small aberration complementary conception is adopted to reduce the tolerance sensitivity of the optical system. Finally, the tolerance analysis is performed to the design result. The results of tolerance analysis show that optical design characteristic requirement can be better met.

Compressive sensing theory is led to super-resolution imaging technology for the general sparsity of most images, and an optical imaging system with all phase reflective compressive coded aperture is proposed based on 4f optical system. Reflective space optical modulator is used to perform optical system imaging experiments and the system is simulated through MATLAB program, the images with high resolution is obtained through decoding and reconstructing the collected single frame image with low resolution. Experimental results show that the best reconstruction effect can be obtained at the condition of ensuring CCD camera matching to spatial optical modulator pixel size completely.

LED light source can be collimated by total internal reflection (TIR) structure which is widely used in LED secondary optic system design. By adjusting the total reflection surface of TIR structure, the circular illumination with small divergence angle is realized. The lenses with 5° and 10° half divergence angle are designed and the simulation experiments are performed. Simulation results show that the expectation requirements can be met and half divergence angle is 5° and 10° respectively with a point source or a 1 mm×1 mm LED source. This method can also be applied to design the lens with small divergence angle.

According to the problem of low efficiency of coupling between semiconductor laser and optical fiber, combining with the characteristics of the outgoing beam of the semiconductor laser, geometrical optics method is used to design aspheric and cylindrical lens. ZEMAX software is used to carry on the simulation about the lens system. And the simulation results provide support for lens module fabrication and experimental verification.

The temperature characteristics of diffractive optical element are analyzed. An infrared athermal imaging optical system at MWIR bands and 5.2° field of view is designed by using diffractive optical element. Design results show that the image quality of the system approaches the diffraction limit in the working temperature range of -55 ℃ to +80 ℃, and the entire field of modulated transfer function (MTF) at 33 lp/mm is more than 0.5. The maximum diameter and the total length of the optical system are 110 mm and 90 mm respectively, which meets the technical requirements.

An underwater low light imaging optical system is designed to improve imaging effect, resolution and sensitivity of underwater video. Image intensifier assembly is used to increase the sensitivity of underwater monitoring system. Optical lens and illumination light sources with large relative aperture and large field of view (FOV) angle are used at the same time. An underwater low light level monitoring imaging objective with 1/2 relative aperture and 50°underwater FOV angle is designed with 10 optical elements through optimization combination based on inverse telephoto structure. Quality assesments show that the optical system has an excellent imaging quality, modulation transfer funtion (MTF) is better than 0.5 at 65 lp/mm, and all the specifications meet the requirements of underwater low light level monitoring.

A new 2 μm high repetition frequency Ho:GdVO4 solid state laser operating in room temperature conditions is introduced. Firstly, the absorption spectrum of the Ho:GdVO4 crystal is measured with a spectrophotometer in room temperature, and the absorption cross-section of Ho:GdVO4 crystal at 2 μm is obtained by J-O theory. Secondly, through measuring and calculating, the fluorescent spectrum, the emission cross-section at 2 μm is got. Finally, the wavelength of pump source is defined based on the absorption spectrum, the maximum average output power of 11 W is obtained at 30 kHz pumped by a 1 942 nm Tm-fiber laser.

The mode field distributions of 7-core optical fiber are simulated by using COMSOL software. It is found that far field with in-phase mode presents quasi-Gauss distribution, which has small divergence angle and the best beam quality. In-phase mode with the best beam quality is proved through analyzing beam quality factor M2 and power-in-bucket (PIB).

Now digital image has become a kind of significant source for obtaining information taking account of its large capacity, high transmission speed, far transmission distance and so on. Alike other information transmission means, digital image may be subjected to noise as well. So various kind of denoising means has been put out. A new nonlinear and adaptive statistics filtering algorithm for image pulsing noise is presented. And experimental data show that the algorithm is easy, feasibly and has stable filtering effect.

With the development of small satellite technology, the requirements for satellite payload weight and volume increase stringently, and the functional mission is getting more and more complex. A small satellite image processing system for high function density and performance based on system reconfiguration technology is proposed. An image processing system reconfigurable platform with small size, light weight, fast response speed, low power consumption and high reliability is designed to realize fast switching among different images at different mission stages. And system stable operation is ensured through redundant design to meet the requirements of space operation environment.

A design method of 32-point real sequence fast Fourier transform (FFT) based on field programmable gate array (FPGA) is presented. Base-2 DIT algorithm and parallel iterative processing scheme are adopted. Cyclone IV series chip of Altera company is chosen and Verilog HDL input method is used to implement design input. It is found that the design can achieve high speed A/D sampling data processing accurately and in real time through contrast of signal tap and Matlab data.

A decoder system with double entry revolving transformer is designed based on the principle of double entry revolving transformer. The system converts revolving transformer input sine and cosine signals into a parallel natural binary digital word using the high accuracy analog digit conversion function of AD2S80A convert which is produced by the AD Company. And the parallel data from decoded AD2S80A is performed combination, calculation and error compensation using CPLD. The decoding principle of the double entry revolving transformer decoder system is introduced. The hardware combination and error compensation software flowchart are designed based on decoder principle to provide a feasible method to high accuracy decoder system of double entry revolving transformer.

The stepping motor control technology in reflection element is introduced. The sampling methods such as natural sampling method, symmetrical and asymmetrical regular sampling methods are compared, the importance of the asymmetrical regular sampling method is presented. And combined with practical application, the key steps of the control technology of the stepping motor with irregular sampling method are described. Choosing turning point and the key function of anti-dead-zone setting are presented. The application value of the technology in the realization of fast, accurate and high robust stepping motor control is defined through the practical application of the reflection element.

The influence on laser-guided weapons carried by the helicopter under typical operational environment such as haze, fog and rain is analyzed. Engineering models are established to calculate the extinction coefficient of 1.06 μm laser under different environments so as to provide references for the laser-guided model influenced by different weather environment during helicopter combat simulation.

Based on traditional ground target recognition systems, a new ground target recognition system based on multi-sensor information fusion, using visible light sensors and infrared sensors, is developed in order to get effective target information in the cases of night, rain, snow and smog. Firstly, Gaussian template mean filter is adopted to the visible light image, and median filter is adopted to the infrared image. And then, the inter frame difference method and background difference method are combined to realize the detection of the moving target. An algorithm based on the coordinates of the center of gravity connected domain mark is presented and the target area is located successfully. Secondly, the Haar-like rectangular features are used to represent the vehicle, the original characteristics library is expanded and rotation single rectangle features are added to describe the vehicle shadow region. Finally, the traditional AdaBoost algorithm is improved and the visible light and infrared vehicle classifier is trained successfully. Experimental results show that the system has some practical value and research significance.

By measuring the infrared radiation characteristics of jet airplane exhaust plume, the intensity and distribution of infrared radiation in 8~14 μm long band are obtained. Measurement results show that the exhaust plume radiant intensity at 180° direction distributes to ring and the radiation is concentrated near the engine nozzle outlet. The maximum radiant intensity and the plume area of after burner are 2.4 times and 1.3 times of non-after burner respectively. The exhaust plume radiant intensity at 90° direction distributes to symmetric envelope, the maximum radiant intensity and the plume area of after burner are 1.8 times and 2.3 times of non-after burner respectively.

Light scattering characteristics of missile gas plume typical particles are analyzed in theory and calculated numerically by using Mie's scattering theory, the relationship between the extinction, scattering coefficient, scattering intensity distribution and the particle diameter are obtained. The results show that the laser scattering effect of missile plume is obvious through theoretical calculations of scattering accounted for more than 50% of the total extinction. And typical missile gas plume omnidirectional scattering energy distribution is calculated, which provides theory support for related system design.

The jamming effectiveness of the towed decoy of the subsonic target flying at super low altitude in the test against the air defense missile with different guidance system is analyzed. Firstly, the jamming effectiveness of the towed decoy on the shipboard radar is analyzed on the basis of reasonable assumptions of the length of the towing cable and the route shortcut. And then, the process and the effectiveness of the towed decoy against air defense missile weapon with radar and infrared guidance system are analyzed. At last, based on typical trajectory simulation example, the guidance process of the missile is analyzed quantitatively and the views about the use of the towed decoy in test are proposed.