Research On Key Techniques Of High Performance Miniature Infrared Thermal Imaging System

The uncooled infrared thermal imaging technology has been the key one that countries in the world widely developed due to its comprehensively meeting of the military application requirements. In recent years, with the growing of the science and technology, the uncooled infrared thermal imaging technology has achieved fruitful results. However, the research in this filed started late in China and has been lagged far behind the top-level. Therefore, the main task is developing the independent research ability in aspect of the uncooled infrared thermal imaging technology in order to enhance the homeland security and national defense construction.In this paper, a high performance miniature uncooled infrared thermal imaging system is designed based on the analysis and the improvement of the key technologies. The main works are as follows:(1) The technical parameters of the system were determined. And the power module, driver module, conversion module and processing module were designed respectively.(2) For the design of the power circuit, the SR-Buck and LDO were selected to meet the requirements such as high efficiency, low power dissipation and low noise.(3) For the design of the analog circuit, the circuit structure consists of the high resolution DAC, RC filter and the OPA was used. The low noise circuit and appropriate bias voltage were chosen to ensure the analog circuit operating in a low noise condition.(4) As for the high speed digital circuit, both the size and power dissipation were taken into account to complete the design without matched resistance.(5) Some conclusions have been obtained. Firstly, the system is verified to be working quite well. It is indicated that the rms noise is 534 μV, σt and σtv are 73μV and 158μV, respectively. Secondly, the DDRII module was proved to be working well which can be used for producing images in the future. Finally, based on the above results, it is concluded that the relevant image processing algorithms play a significant role in improving the performance of the system imaging.