In order to guide the machining of a 600 mm hyperboloid mirror, the detection system of Ronchi grating is designed. In view of the stray light phenomenon in the process of system detection, the causes of the phenomenon are analyzed, and the corresponding solutions are put forward. The analysis results show that when the residual reflection of the splitting prism is greater than 5%, the illumination of the dark fringe on the image plane increases by 27 times, and the contrast of the fringe decreases, making it difficult to distinguish. With the increase of the residual reflection of the grating, bright spots appear in the center of the fringe, and the fringe cannot be distinguished. The background illumination of the bright spot area of the spectroscope is increased by more than 40 times by the striped surface, and the background illumination of the bright spot area of the glass surface is increased by more than 80 times. By optimizing the system structure, the spectroscope and grating are replaced and treated. The stray light phenomenon is effectively solved and the contrast of the image plane fringe is improved.

The micro Raman scanning test was carried out on InSb wafer before and after heat treatment. A new characterization method of stress surface distribution of InSb wafer was developed. The transverse optical (TO) phonon scattering peaks of InSb before and after heat treatment are 179.3 cm-1 and 178.5 cm-1, respectively. The longitudinal optical (LO) phonon scattering peaks of are 188.8 cm-1 and 188.7 cm-1, respectively. The half-peak widths of characteristic peaks are 5.8 cm-1 and 5.0 cm-1, respectively. The half-peak widths of X-ray dual-crystal diffraction curves are 12.10--20.04 arcsec and 7.61--7.74 arcsec, respectively. For devices made of heat-treated InSb wafers, the increment of blind element is less after baking at 80℃ for 20 days, and the overall quantity is small. This indicates that the heat treatment releases the residual stress of the wafer, which has a favorable effect on the new blind pixel in the late suppression device, and lays a material foundation for the preparation of a new generation of infrared detector with ultra-high performance and ultra-large size.

As an important process in surface polishing of CZT substrate, the surface quality and production efficiency of CZT substrate are determined by the polishing results of CMP. Polishing fluid is one of the key influencing factors of CMP, which directly affects the surface quality of substrate after polishing. In this paper, the polishing liquid used in CMP process of CZT substrate is studied. The effects of silica sol and hydrogen peroxide on the surface quality and removal rate of the substrate are investigated under different pH values and abrasive concentrations. The results show that the high efficiency processing can be achieved by using the modified polishing liquid to perform CMP on CZT substrate while an ultra-smooth surface is obtained, which lays a good foundation for mass preparation of CZT substrate with high surface quality.

The mid-infrared (MIR) quantum cascade lasers (QCLs) have been widely applied in the fields such as directional infrared countermeasure, free-space optical communication, trace gas sensing, and other important fields. We further improve the theoretical approach for self-consistent solution of the Schrdinger equation and the Poisson equation based on the MIR QCL device using the Nextnano++ software. We calculate the electronic subband structure in the active region of the four-level and double-phonon resonant QCL structure for GaInAs/AlInAs multi-quantum well-based MIR QCL devices grown on InP substrate. The dependence of these subband energies upon device operating temperature, driving electric field, and doping concentration in the injection region are studied. Theoretical findings are in line with the experimental results. This work provides theoretical design and research methods for the growth and preparation of MIR QCL devices, provides theoretical expectations for understanding the working conditions of devices, and provides theoretical research support for further improving the luminescence power and efficiency of MIR QCL.

Terahertz (THz) waves have potential applications in wireless communication, biomedicine, nondestructive testing, military radar and other fields. It is of great practical significance to study THz slow light response to THz communication and detection technology. At present, the reported researches on the slow light effect of THz still face a series of problems. Because EIT metamaterial has a flexible structure and designable electromagnetic properties, it offers a new research platform for THz slow light effect. In this paper, the basic principle and research progress of THz slow light effect based on EIT metamaterials are introduced, and the development trend of THz slow light effect is analyzed and prospected.

In order to provide testing support for the development and production of terahertz instruments such as terahertz source and terahertz detector, a terahertz power measuring instrument based on phase-locked amplification principle is developed. At present, many commercial phase-locked amplifiers are expensive, bulky and complex in structure and function, which are not suitable for some portable detection systems. The instrument mainly uses a phase-locked amplification scheme based on AD630 to monitor weak signals. AD630 phase-locked amplifier has low cost, simple design structure, strong flexibility and high integration. When the terahertz power measured by the standard terahertz power meter is 96.8 mW and 2.98 W, the power measured by the terahertz power measuring instrument developed in this paper is 97.9 mW and 3 W respectively, and the error range is within ±5%. The phase-locked amplification scheme based on CD552-R3 weak signal can only extract millivolt level signals, while the scheme in this paper can extract microvolt level signals. Therefore, the proposed scheme is used to detect terahertz power with a wider range and higher stability.

In order to realize the effective protection of avalanche diode of military laser rangefinder, the basic properties of VO2 film under 1064nm laser irradiation are tested, and the relationship between transmittance and film thickness before and after phase transition is obtained. The influence of different thickness of VO2 film on the minimum saturation incident laser threshold of C30950E avalanche diode is also obtained, and the fitting formula is given as well. The experimental results show that with the increase of film thickness, the minimum saturation incident laser threshold of avalanche diode increases gradually. The minimum saturation incident laser threshold of avalanche diode can be increased from 5×10-6W to 1.2×10-5W when the film thickness is 200 nm. At present, there are few researches on laser protection of avalanche diode of military laser rangefinder in China, and most of them are limited to the theoretical level and lack experimental data support. Therefore, the feasibility of using VO2 thin film for avalanche diode protection of military laser rangefinder can be further verified by the data and fitting formula provided in this paper. The data reference is also provided for further research on avalanche diode protection of various laser ranging equipment.