The Research On High Frame Rate Imaging Based On MEMS Uncooled Infrared Imaging System

Recent years, uncooled infrared imaging system using optical readout method based on MEMS has become a new hotspot in domestic and external infrared imaging field. This infrared imaging system has advantages such as uncooled, no scan, light weight, low power consumption and high resolution. Also it has been one of the most important developing directions in infrared detecting field. At present, the domestic and international research on the imaging system focus on the imaging quality of the system, but there are no relevant reports about the frame frequency and response time of the imaging systems. Studies of increasing the FPA frame frequency will be an important research direction in the future.The response time of FPA is the focus of this paper. Presently there are two main factors that limit FPA imaging speed. For one thing, we can improve the intrinsic response speed of FPA by optimizing the design and improve the fabrication process. For another, because the environment influences the response time of the detector, we can increase the response speed by changing the environment. The thesis focuses on the response time of the system and the main research contents are as follows:(1)A new glass substrate is proposed to calculate the response time of FPA.The main factors——heat capacity and thermal conductivity, which influence the FPA response speed, is analyzed by giving the concept of thermal response time. The relationship between the thermal response time of FPA and ambient temperature, so is barometric pressure, is discussed.(2)An experiment is designed to measure the thermal response time of FPA with different ambient temperature and barometric pressure by applying the impulse response test method. The results accord is well with the theoretical analysis.(3)By using the imaging system in laboratory, we get the thermal images of different high speed thermal target. Through continuously changing the imaging frame rate, finally we get the frame rate limit of system. It is proved that the imaging quality of this high frame rate system is verified to be acceptable.(4)Respectively we get the thermal images of the same thermal target in visible light and uncooled FPA imaging system, we get the thermal video images under different conditions. The result proved that the FPA infrared imaging system can gain more information.