The energy band and defect energy level state are important parameters in the manufacturing process of narrow band gap semiconductor material chips. Infrared modulated photoluminescence(PL)spectrometer is a non-destructive and effective detection technology. This technology is used to detect different narrow band gap semiconductor materials. The spectral results are fitted with a line type to reveal the electronic transitions between different energy levels, and the results are analyzed. The results show that infrared modulated PL spectroscopy is an effective method for studying energy bands and defect energy levels of materials.

In the test process of multi-element infrared detector, the traditional method usually uses the way of analyzer collection and manual reading to achieve the data acquisition. The analyzer, preamplifier,gas source and fixture work independently, and the collected data need to be edited again with low efficiency. In order to achieve accurate automated engineering test and the control integration of the gas source and fixture at the same time, the PULSE multi-analyzer of Denmark B&K company is used as the acquisition terminal, and the acquisition and control software is re-developed by using VBA program. In this way mentioned above, the automated test is achieved. In this paper, the noise source of amplifier in the process of system establishment is analyzed, and the relationship between noise coefficient and source impedance is fitted. It is illustrated that the key to achieve low noise amplification is the optimal source impedance match between the detector and the preamplifier. In addition, the first stage of the amplifier is designed to be multi-channel parallel, and the switch is used between the second stage and the first stage to maintain the consistency of the channels. Finally, through the combination of the software and the hardware, the automated test of real-time and multi-channel fast Fourier transform analysis of the detector is realized.

This paper introduces the basic principle of auto-focus technology in infrared systems, and analyzes in detail the influence of focusing mechanism backlash on the traditional auto-focus algorithm. A variety of optimized schemes are proposed， and the applicability and stability are fully considered. Finally, an experiment is designed to verify the feasibility of the algorithm which realizes fast, stable and accurate auto-focus， and the algorithm can be used in engineering practice.

With the development of fiber grating sensing and the increasing demand of vibration testing technology, the research on fiber grating vibration sensor has been carried out rapidly. In this paper, the principle of the fiber Bragg grating （FBG） based vibration sensor is introduced. In addition, the research on FBG vibration sensor in recent years is summed up in terms of different structural types, with emphasis on the cantilever beam and diaphragm structure. The advantages and disadvantages of different fiber grating packaging methods of the same structure type are expounded. Based on the research and analysis, four factors are proposed to optimize the performance of the FBG vibration sensor. Finally, the development of the FBG vibration sensor is prospected.

Starting from some uncontrollable cases of current artificial intelligence (AI), the fragility and uncertainty of artificial intelligence are associated, and the methods of improving the controllability of artificial intelligence are tentatively proposed. The article is mainly divided into five parts. The first part briefly describes the proposal and development of AI. The second part introduces the specific uncontrollable cases of chat robots and other AI products. The third part mainly discusses the sources of AI technology fragility and uncertainty. The fourth part puts forward some suggestions for improving the controllability of AI, including enhancing the scenario awareness ability of AI, deploying controllable nodes in the system architecture and improving the supervision and evaluation system through the controllable nodes. The fifth part describes the prospects of AI technology in the field of optoelectronics.

The Dougong of "Tiangong Pavilion" in Gongshu Hall, Qi Village, Hu County, Shaanxi Province is studied, which was made in the Ming Dynasty. Fourier transform infrared attenuated total reflection(FTIR-ATR) is used to study the changes of chemical composition and structure of the minor carpentry work. The retention rates of hemicellulose, cellulose and lignin in the minor carpentry work are calculated according to Lambert-Beer Law，and the decay degree of wood components is studied. The results show that FTIR-ATR method is accurate, rapid, nondestructive and reproducible in the quantitative analysis of the main components in wood. Due to long-term exposure to air, the wood components are affected by humidity changes, microorganisms, ultraviolet rays and other factors in the environment. The hemicellulose which is filled and bonded in the wood has been basically completely degraded. The strength, toughness and bearing capacity of wood components are reduced, so it is necessary to strengthen the wood components. The results can provide robust data support for future protection and restoration of cultural relics.