Low Noise Uncooled Infrared Detector Component Design Research

The infrared detection technology plays an important role in the foundation of both national defense and civil applications, which become a significant part of the national information construction in the new centuries. After years of research, the developed countries have been developed the third generation detector with uncooled IRFPA(Infrared Focal Plane Array) technology, which began late in our country. There still exists a gap in this area between developed countries and our county. However, we have made a series of progress on uncooled IRFPA in recent years, which correspondingly prompts the research of infrared detector components. With the improvement in low noise performance of IRFPA, designing and developing new detector components to adapt the low noise IRFPA detector have become an urgent problem.Based on the analysis of the low noise performance of IRFPA, in this article a low noise components design idea was propsesd, starts with the modular design of the power supply circuit, bias voltage circuit, timing-driven circuit, data conversion circuit and data processing circuit. It also takes a full consideration of the low noise design and small scale performance of the circuit, and mainly reflected in three aspects. Firstly, both analog and digital power supply are isolated in the design of the power supply module, and decoupling and differential network are implemented in the data conversion circuit. Secondly, a16-bit resolution DAC chip is used in the bias voltage module to provide analog voltage, and the system integration is greatly improved with the application of the I2C communication protocol. Thirdly, the dead pixel compensation algorithm and the two point non-uniformity correction algorithm are implemented in the data processing circuit to improve the imaging quality.After debugging and test, for digital part, the digital output voltage of the power supply circuit meets the design requirements, and for analog part, noise RMS value of the5V voltage is32.4μV(1Hz-100kHz), The bias voltage circuit has accomplished the configuration of the three channels analog bias voltage simultaneously. The adjustable range is between0-5V, and the noise RMS value is less than20μV(1Hz-100kHz), with the application of the differential network, the noise of the IRFPA reduce from248μV to231μV. Experiment results show that the two point non-uniformity correction method can reduce the FPN noise effectively, thus significantly improving the detector’s imaging quality. The design of the low-noise components has provided a new hardware platform for the further development of the detector.