The advantage of polarization imaging technology is that it expands the amount of information from three degrees of freedom, namely light intensity, spectrum, and space, to seven degrees of freedom, including light intensity, spectrum, space, degree of polarization, polarization azimuth, polarization ellipticity, and direction of rotation. This richness of observational information is conducive to improving the accuracy of research target detection. This article first introduces the research progress of polarization imaging technology at home and abroad in recent decades, then introduces the typical applications of polarization technology in military and civilian fields, and finally provides reasonable suggestions on the problems of polarization imaging technology in our country.

With the rapid development of infrared detection technology, the improvement of the infrared stealth capability of military targets has become an urgent problem to be solved, so it is of great significance to study infrared stealth materials. This paper briefly analyzes the stealth mechanism of infrared stealth materials, summarizes the research status of four types of infrared stealth materials in recent years, such as low infrared emissivity materials, temperature control materials, photonic crystals, and intelligent infrared stealth materials, and forecasts the future development trend of infrared stealth materials.

To ensure that researchers are well-informed regarding infrared image edge detection algorithms and to provide a valuable reference for follow-up investigations, we review relevant research conducted on infrared image edge detection algorithms in the past ten years. First, infrared imaging and edge detection technology are summarized, and then, the difficulties and challenges of infrared image edge detection algorithms are described. Finally, the main infrared image edge detection algorithms are summarized, and the related algorithms are divided into four categories: improved classic edge detection operator-based algorithms, ant colony algorithm-based algorithms, mathematical morphology-based algorithms, and network model-based algorithms. Considering traditional infrared image edge detection algorithms, the morphological method has potential because of its simplicity and ease of use; for non-traditional infrared image edge detection algorithms, the method based on deep learning has stronger pertinence, better robustness, and no requirement of designing complex algorithm steps, which brings new development opportunities to infrared image edge detection.

To meet the requirements of the micro-miniature air-to-air missile and solve the problem of not reaching full field angle, this paper presents a micro-miniature infrared seeker with roll-pitch structure, applying the integration philosophy of optical-mechanical structure and pitching shaft. Compared with the classic roll-pitch frame, this new structure combines two individual pitch shafts; additionally, the optical-mechanical structureusesonly one mechanical part, thus greatly reducing its size. Moreover, this new structure has a focus function that could improve the image quality. After structure design, we conducted thermo-mechanical coupling analysis on structure parts and lens under eight extreme conditions. The results show that the optical-mechanical structure meets the requirement of micro-miniature(80 mm), shock resistance (10g), and high low temperature test (-40℃~60℃). The simulated analysis can predict real conditions and has great guiding significance for optical-mechanical structure design.

Graphene is a two-dimensional material with high mobility, high thermal conductivity, high transmittance, large specific surface area, and good mechanical strength. It is widely utilized as a transparent electrode and charge-transporting layer in optoelectronic devices. However, graphene is a zero-bandgap material with inherent semi-metallic properties that limit its application in the field of semiconductor optoelectronic devices. The construction of heterojunctions has become a critical means to meet the requirements of semiconductor applications in specific industries. To date, many different graphene heterojunction structures have been reported owing to the wide selection of heterojunction materials. Based on the properties of graphene, this study describes the development and preparation methods of graphene heterojunctions and summarizes the research progress of photoelectronic devices based on graphene heterojunctions from the perspective of material preparation and device structure. Lastly, the development of graphene heterojunctions in optoelectronic devices is discussed.

In infrared image processing, owing to technical issues with the infrared detector, the original infrared image includes a variety of noise, especially salt and pepper noise, fixed noise, or random stripe noise. Currently, there are many filtering algorithms for infrared image denoising, but they emphasize time, space, denoising effect, maintaining detail, and so on differently; therefore, it is difficult to achieve a perfect combination. Identifying methods to filter noise information more quickly, efficiently, and accurately and retain more details is an important future research direction for noise reduction in infrared image processing. This study investigated and compared the current mainstream infrared image denoising algorithms from three categories: traditional filter denoising, transform domain filter denoising, and image layered processing filter denoising, and a combination of a traditional algorithm and image layered adaptive denoising algorithm is proposed to provide a reference for future studies in related fields.

Typical individual combat scenarios were presented, which include battlefield observation, reconnaissance and surveillance, target positioning and laser designating, light weapon precise shooting, sniper warfare, fighting with targets hidden in trenches, parachuting and airlanding at night, night fighting, entering indoor or dark underground space from the bright environment, observing/searching/shooting in the low-visibility environment. To meet these battle requirements, individual soldier night vision goggles have been developed to integrate with visible light scope, laser rangefinder, satellite positioning system, digital compass, communication and other functional modules. Therefore, night vision goggles possess more complex and accurate combat capabilities, such as night vision imaging, range finding, positioning, calculating, information fusion, fire control computing and wireless transmission.

Low SWaP (size, weight, and power) applications are typical features of thermal imaging systems based on HOT(high operating temperature) detectors. The system performance is comparable to that of a cooled infrared system, with reduced manufacturing costs. They have important application value and are promising prospects for high volume production. The structural features of barrier detectors are introduced, and the structures of the materials used for the barrier detectors and their impact on system performance are analyzed. Other technologies used for HOT detectors are also summarized. Finally, the current research progress on barrier infrared detectors is summarized. Additionally, several future research directions for HOT detector technologies are presented.

Terahertz (THz) waves are located between the infrared and microwave bands. Compared with other bands, they have the characteristics of high transmission, low energy, coherence and transient nature. With the widespread application of terahertz imaging technology in the fields of space communication, radar detection, aerospace and biomedicine, it has been shown that THz imaging offers advantages over traditional imaging technologies (such as ultrasonic imaging and X-ray imaging). This paper first introduces the development status of THz time-domain spectroscopy (THz-TDS) imaging technology and room temperature (uncooled) microbolometer THz imaging technology. Subsequently, typical applications of THz imaging technology are presented. Finally, the limiting factors of THz imaging technology are discussed.

In recent years, the type Ⅱ superlattices (T2SL) infrared detector has experienced incredible improvements in material growth, device structure design, device fabrication techniques, which make the T2SL become the most popular infrared detector material, besides HgCdTe. This article briefly introduces the advantage of the T2SL material, summarizes the international research status in T2SL-based photodetectors, reviews the history of technology development of T2SL-based photodetectors and analyzes the drawback of the research of T2SL material and device technology in China.

Dynamic range compression of infrared images is an important research direction in the field of infrared image visualization. The dynamic range compression algorithm directly determines the important visualization indexes of the original infrared image, such as detail retention and overall perception; in a sense, it is the basis and guarantee of detail enhancement. This study investigates a wide dynamic range compression algorithm and a local compression algorithm based on a global compression algorithm. Based on the two algorithms, we study and analyze the development process and the advantages and disadvantages to improve the research direction and development trend, which will provide a reference for researchers.

Multi-modal image registration can provide richer and more comprehensive information than single-modal image registration. Among them, infrared and visible image registration, which is a common multi-modal form of registration, has important application value in fields such as electric power, remote sensing, military, and face recognition. In this paper, the correlation technique of infrared and visible image registration is introduced, and the existing difficulties and challenges involved in registration are analyzed. Subsequently, the advantages and disadvantages of different registration methods are evaluated in detail the three types based on area, feature, and deep learning, and a practical application of infrared and visible image registration technology is presented. Finally, the future development trend of infrared and visible image registration is discussed.

This paper presents the technical characteristics and performance of high performance super second generation image intensifier, compares it with ordinary super second generation image intensifier, and puts forward the technical measures to further improve the performance of high performance super second generation image intensifier. Super second generation image intensifier is a kind of image intensifier with higher performance over second generation image intensifier. It was developed by application of new technology, new craft and new material on the base of the second generation image intensifier. After nearly 30 years of development, its performance has been greatly improved. In recent years, due to the use of grating window on the super second generation image intensifier, the sensitivity of the Na₂KSb photocathode is over 1000 μA·lm^-1, and the resolution is above 17 lp·mm^-1 on the illumination of 10^-4 lx. It would be predicted that the sensitivity of Na₂KSb photocathode will reach 1350-1800 μA·lm^-1, and the signal-to-noise ratio will reach 35-40 by further improving the fabrication process of Na₂KSb film and optimizing the structure of grating. It would be predicted that the resolution will reach 81 lp·mm^-1through use of microchannel plate of 4 (m diameter and fiber optical plate of 3 μm diameter, the resolution is likely to reach 81 lp·mm^-1.

With the development of ultraviolet detection technology, oxide materials showing the unique advantages in the field of ultraviolet detection, which the traditional detectors didn't possess, and becoming a hot research topic in recent years. It is a fast-developing dual-purpose detection technology after the infrared detection technology. However, the wide applications of oxide-based ultraviolet detectors still face challenges. In this paper, we have summarized the applications and development histories of the ultraviolet detection technology at home and abroad. The crystal structures, properties and progresses in devices of three kinds of metal oxide ultraviolet materials are summarized and discussed. In the end, the problems in the research of the oxide-based ultraviolet detection materials and devices are analyzed, and the development of the oxide-based ultraviolet detection technology is summarized and prospected.

Driven by the concept of SWaP³ (Size, Weight, and Power, Performance and Price), the development of the third-generation cooled IR detectors is proceeding in the direction of high performance, miniaturization, and light weight. As core military electronic devices, the reliability of IR detectors has become the focus of research. In this study, based on the 640×512/15 μm miniaturized dewar developed by Zhejiang Juexin Microelectronics Co., Ltd., a systematic reliability research is carried out. This research involves four dimensions, namely mechanics, thermodynamics, remainders, and vacuum. The performance of the 640×512/15 μm miniaturized dewar is evaluated through reliability tests. The results show that the miniaturized dewar has high reliability to satisfy most military needs.

Super-second-generation and third-generation image intensifiers are two types of image intensifiers that use different technologies. Super-second-generation image intensifiers employ a Na₂KSb(Cs) photocathode, whereas third-generation image intensifiers employ a GaAs photocathode. Third-generation image intensifiers employ higher cathode voltages than those employed by super-second-generation image intensifiers. In addition, third-generation image intensifiers employ an antireflection coating between the glass input window and GaAs photocathode; however, this is not employed in super second-generation image intensifiers. Furthermore, third-generation image intensifiers employ ion barriers on their MCP(microchannel plate), whereas super-second-generation image intensifiers do not. In terms of limiting resolution, despite the small initial electron velocity, narrow exit angle distribution, and high cathode voltage of the third-generation image intensifiers, the limiting resolutions of the two types of image intensifiers are the same; the advantages of the GaAs photocathode of the third-generation image intensifiers have not been introduced under the existing limiting resolution level. In terms of signal-to-noise ratio, the GaAs photocathode has a higher cathode sensitivity, normally more than twice that of the super-second-generation image intensifier. Thus, theoretically, the third-generation image intensifiers have signal-to-noise ratios that are 1.4 times those of the super-second-generation image intensifiers. However, the two types of image intensifiers are basically the same owing to the influence of higher cathode voltage and ion barrier transmittance and the advantage of not introducing the high sensitivity of the GaAs photocathode of the third-generation image intensifiers. In terms of gain, although the third-generation image intensifiers have higher cathode sensitivity and cathode voltage, the super-second-generation image intensifiers compensate for the shortcomings of cathode sensitivity and cathode voltage by increasing the working voltage of the microchannel plate. Therefore, in terms of the existing image intensifier gain, the gains of the two types of image intensifiers are identical. In terms of equivalent background illumination(EBI), owing to the higher sensitivity of the GaAs photocathode, the third-generation image intensifiers can obtain lower equivalent background illumination under the same photocathode dark current. Therefore, the third-generation image intensifiers have higher initial contrast than that of the super-second-generation image intensifiers. The higher the initial contrast of the input image, the higher the contrast of the output image. In terms of halo, because the photocathode of the third-generation image intensifiers has high sensitivity and an ion barrier film, theoretically, the third-generation image intensifiers have higher halo brightness than that of the super-second-generation image intensifiers. However, in actual situation, the halo brightness levels of the two types of image intensifiers are basically the same. In terms of stray light, the GaAs photocathode has an antireflection coating; thus, the stray light is lower than that of the super-second-generation image intensifier, so the imaging of the third-generation image intensifier is clearer and the sense of gradation is better. In terms of spectral response beyond the long-wavelength threshold, because the spectral responses beyond the long-wavelength threshold of the super-second-generation image intensifiers are higher than those of the third-generation image intensifiers, the super-second-generation image intensifiers have better imaging performance than that of the third-generation image intensifier under supplementary illumination using the near-infrared waveband. For example, without the presence of any light, the super-second-generation image intensifiers can obtain better images at a supplementary illumination of 980 nm wavelength, whereas the third-generation image intensifiers cannot. In terms of the resolution of low illumination, the super-second- and third-generation image intensifiers with similar performance parameters have the same low luminance resolution. It should be noted that this conclusion was obtained under the test conditions of a standard A light source. When the actual environmental emission spectrum distribution is different from that of a standard illuminant A, the low illumination resolutions of the two types of image intensifiers are different. Photocathode sensitivity is a parameter of the photocathode and not of the image intensifier. Thus, the performances of the two types of image intensifiers cannot be compared in terms of photocathode sensitivity. The difference between the super-second and third-generations cannot be understood using the meaning of "generation; " their differences do not lie in the meaning of "generation."

The cut-off wavelength of the spectral responses of the Ⅲ-Ⅴ semiconductor alloys InAs_1-xSb_x can be changed from 3 to 12 μm by tuning the relative amount of antimony in the alloy at room temperature. In addition, with longer carrier lifetime, higher optical absorption coefficient and higher carrier mobility can be achieved. InAsSb is a type of prospective MWIR and LWIR detector material that has potential applications. InAsSb detector can work at 150 K even at near room temperature with higher sensitivity and detectivity. Hence, it is one of the best choices for low-power, miniaturized, low-cost, highly sensitive, and fast-response MWIR and LWIR detection systems. InAsSb detectors have been widely studied and developed. In this paper, the fundamental material properties are described. Next, the status of the InAsSb infrared photodetectors domestic and abroad is introduced. Finally, the development of the InAsSb infrared detection technology is summarized and prospected.

Here, a novel method for measuring an aspheric surface using an infrared laser interferometer is proposed. The model is divided into three modules. First, the wave front aberration between the aspheric surface and the standard spherical surface was measured by an infrared laser interferometer. Then, the theoretical value of the wave image difference between the aspheric surface and the standard spherical surface was calculated according to the aspheric equation. Finally, the surface shape deviation of the aspheric surface was calculated. To verify the validity and reliability of this method, the surface shape error of the same paraboloidal mirror was measured using the ZYGO visible light interferometer and the compensation mirror method. The obtained results indicate that these two measurement methods were identical. Hence, the novel method is convenient, fast, and highly versatile and can be used to test aspheric surfaces during processing.

Quantum dots (QDs) are widely used in photoelectric detection, biomedicine, new energy, and other fields because of their quantum limitations, size, and surface effects. Recent years have seen midwave infrared (MWIR) quantum dots (QDs) become a focal point in infrared research. By adjusting and controlling their size, these QDs can extend their absorption wavelengths in the infrared spectrum. Therefore, the successful preparation of infrared QD materials and devices is crucial for infrared imaging, guidance, search, and tracking. This study first introduces the preparation and synthesis technology of five types of MWIR QDs materials, HgSe, HgTe, PbSe, Ag₂Se, and HgCdTe, analyzes the size and morphology, lattice fringe, and infrared absorption spectrum characteristics of the QDs, and then summarizes the domestic and foreign MWIR QDs detectors. The device structures and preparation methods of the detector are summarized, and the photoelectric performance parameters, such as responsivity, detectivity, and response time, of the detectors are compared and analyzed. Finally, the development of MWIR QDs was discussed.