The definition and classification of the infrared radiation sources of aircraft target are introduced. Based on the requirements of engineering calculation, the physical models of infrared radiation are summarized for aircraft skin, engine nozzle and tail flame, respectively. The development statues of the spectral radiation characteristics of aircraft target are systematically investigated at home and abroad, and the spectral radiation characteristics are summarized at different wavelengths and detection angles. Combined with the guidance systems of infrared guided missiles, the matching operational applications of point-type infrared decoy including single point decoy, multi-point decoy, spectral decoy and surface-type decoy are evaluated. This study provides a good guidance for establishing reasonable and effective jamming strategies, which further enhances the survivability of aircraft on battlefield.

The high-temperature rocket exhaust plume has become the focus of the space-based infrared system detection, tracking, classification and identification tasks due to its prominent infrared radiation signatures. The physical modeling and numerical calculation of the emission and transmission mechanism of the plume radiation signatures has always been a hot issue in the field of target detection, and is also developing towards high accuracy and efficiency. Focusing on the various links involved in the infrared radiation calculation link of the plume, the research situation is summarized from the aspects of reacting flow field simulations, radiative parameters of gas and particles, radiative transfer methods and validation of numerical models.

Visible laser has been applicated widely in scientific research, industry, medical treatment and communication. They are currently generated by semiconductor lasers, rare-earth doped lasers and nonlinear frequency conversion techniques. In recent years, visible rare-earth doped lasers have received extensive attention. Firstly, several typical applications of visible lasers are introduced, and secondly the emission, absorption spectra and laser characteristics of rare earth ions such as praseodymium, neodymium, samarium, europium, terbium, dysprosium, holmium, erbium and thulium that can produce visible lasers are analyzed. Finally, the latest research progress of praseodymium and terbium doped solid-state visible lasers is reviewed.

The 2 μm band belongs to the human eye band and has an atmospheric communication window. The research on this band is an area that needs to be developed urgently in the future optical communication system. Compared with quartz glass, soft glass material has a wider light transmission range and can be extended to the mid-infrared band, which is suitable for the 2 μm band optical communication system. A multi-core hollow-core photonic band-gap optical fiber is designed. The characteristics of different modes such as mode area, confinement loss and bending loss are simulated and analyzed. The optimum wavelength for single and multiple mode laser transmission in 2 μm band is given by comprehensive analysis.

Soliton self-frequency shift effect, as one of the nonlinear fiber, acts as an effective wavelength tuning method of ultrashort pulse in fiber due to its unique pulse self-holding property. The soliton self-frequency shift effect in fiber is studied from theoretical calculation and experimental verification. The simulation calculation is based on the generalized nonlinear Schrodinger equation, and the experimental analysis is performed through measuring the output spectrum of polarization-maintaining photonic crystal fiber. The experimental result is in agreement with the theoretical prediction. Both results show that the ultrashort pulse wavelength based on the soliton self-frequency shift effect can realize the continuous tuning over 300 nm in the range of fiber anomalous dispersion region.

The far-field characteristics of the main lobe of two-dimensional coherent array laser beam are studied. The mathematical and physical models of coherent array laser beam propagation with square and regular hexagonal sub light sources are established. Through numerical simulation and analysis, it is concluded that the error of Gaussian function to describe the far-field central main lobe intensity distribution of coherent array laser beam is very small, and the propagation law of coherent array laser beam can be described according to the fundamental Gaussian beam propagation law of single aperture laser. On this basis, the energy ratio of the central main lobe in the far field is calculated. Calculation results show that the energy ratio of the central main lobe in the far field is hardly affected by the number of sub light sources. With the increasing of duty cycle, the energy proportion of central main valve increases gradually. When the aperture of coherent array laser is completely filled, the maximum energy proportion of the central main lobe of square laser beam is 79.1%, and the proportion of regular hexagonal arrangement is 83.2%.

A pulsed semiconductor laser side-pumped Nd:YAG synchronous acousto-optic modulated Q-switched nanosecond laser are reported. Using a Nd:YAG side-pumped module with a continuous output power of 50 W, a stable Q-switched pulse output with an average output power of 2.27 W and a pulse width of 71 ns is achieved when the semiconductor laser is pumped with a pulse width of 250 μm, a repetition frequency of 1 kHz, and an acousto-optical Q-switching delay of 270 μm.

The research status of micro-scanning imaging technology is analyzed, and the infrared imaging system model is established. The technical principle of micro-scanning imaging technology is analyzed, the theoretical simulation of its super resolution capability is analyzed, and the effect of the super-resolution is verified by the actual infrared micro-scanning imaging system, and the imaging results are analyzed and evaluated.

The generation of microwave signals in the optical domain is a hot research topic at present, and it is widely used in communication systems, signal processing, radar and other fields. The frequency and the time domain synthesis methods for generating specific optical pulse signals based on continuous radio frequency modulation and frequency-time mapping technology in the field of microwave photonics are respectively introduced, and several specific schemes of the two methods are introduced in detail. The advantages and disadvantages are analyzed from the aspects of the tuning ability of the pulse repetition frequency, the pulse duty cycle, the pulse type, and the stability of the system structure.

In machine vision systems based on optical techniques, the degradation of hazy images poses difficulties for many applications, especially monitoring and early warning in the field of public safety, such as motion monitoring of drone flight, fixed video surveillance of police, border monitoring system, etc. The existing dehazing algorithms based on deep learning trained by synthetic datasets are also difficult to be applied to the above environment. To this end, a single image dehazing algorithm based on unsupervised learning is proposed. At first, by improving the extraction module of the unsupervised dehazing algorithm YOLY, the quality of the obtained image is improved. And then, the brightness of the generated image is improved by adjusting the module parameters. At last, various loss function adjustments are added to further improve the quality of the image. Experimental results show that the image processed by this method has bright colors and complete details, which is closer to the real image, and the image noise is significantly reduced, which has practical application value.

Based on the working principle of millimeter wave radiometer of the terminal sensitive projectile, the smoke screen jamming mechanism and the testing principle and method of interference material emissivity are analyzed and studied. The high emissivity material is dynamically placed above the small iron plate, and the radiation signal of the small iron plate weakens sharply. Testing results show that it is feasible to use the smoke screen formed by the high emissivity interference material to jam millimeter wave radiometer.

Zinc selenide polyhedral reflection prism is an important component of the optical system of a roll-pitch long-wave infrared seeker, which directly affects the imaging quality of the optical system. For prism’s complex polyhedron plane structure and the feature of polycrystalline zinc selenide material, a precision processing of single point diamond fly-turning is proposed. A mathematical model is established for the position relationship of each surface of the prism, and a special tooling to ensure one-time clamping and processing is designed. The turning path is simulated, and the effects of parameters such as spindle speed, cutting depth and feed rate on the surface quality of ZnSe are obtained through experiments. The parameters of the reflection prism is obtained, such as 12″ angle error, PV:0.13 λ surface shape error, 0.02 λ RMS, Ra:7.39 nm surface roughness and Ⅴ surface imperfections. The design requirements are met. And the process method of precision processing ZnSe polyhedral reflection prism by fly-turning is verified.

A classical optical processing method for a class of lightweight silicon carbide mirrors is presented. In the fine grinding stage, the mirror body is subjected to fine grinding experiments with emery and boron carbide respectively. Results show that under the same fine grinding time, the grinding amount of the boron carbide granular abrasive (240#) is at least 0.01 mm larger than that of the emery granular abrasive, and the cutting effect is obviously better than that of the emery granular abrasive, the best process parameters for fine grinding is with a load of 50 N and a spindle speed of 45 r/min. In the polishing stage, using the asphalt polishing mold as the base, the mirror body is polished with cerium oxide polishing liquid and diamond liquid respectively. Results show that the diamond liquid can effectively improve the surface shape and surface quality of the parts. And the optimal process parameters for polishing is with a load of 30 N and a spindle speed of 60 r/min. The mirror body is polished with diamond liquid with two particle sizes of W1 and W0.3 respectively, which can make the mirror body surface best reach 3 low apertures, the surface finish is good, and there are no obvious paths and bright spots. Due to the particularity of the structure of the mirror body, it is difficult to polish the mirror body. A ring polishing machine is used to polish the mirror body without stress and modify the local irregularity of the mirror body. The irregularity of the final part can meet one aperture.