Development Of Short-wave Infrared Cameras

As an important application band in the field of infrared detection,short-wave infrared has important applications in laser communication,industrial detection and detection,communication,biomedicine,night vision monitoring and other fields.Now that optical communication technology is developing rapidly,the use of short-wave infrared technology to capture,detect and analyze lasers has great application value and important research significance.In this theme,a low-power uncooled short-wave infrared imaging information acquisition system is developed for the background of short-wave infrared detection.Since the core of the short-wave infrared camera is the infrared focal plane,It is a detector that uses human radiation to increase the temperature of the sensitive element,so that the resistance value of the resistance can change and then detect the target.It needs to work in a constant temperature environment,so we should design a circuit for temperature control.Short-wave infrared camera contains a semiconductor thermoelectric cooler(TEC),the design uses a temperature control chip MAX1978 to drive TEC,to achieve high-precision temperature control.The entire system uses the FPGA as the main control chip,it uses the amplifier as a voltage follower to isolate the analog signal,and then converts the acquired analog signal into a digital signal through the AD module.The thesis focuses on the hardware composition and circuit design of the system,mainly including the circuit design of the short-wave infrared camera module,the design of the temperature control circuit,the design of the analog-to-digital conversion circuit and the design of the power supply circuit.And the chip selection in each circuit is described in detail.Then some of the key logic in the system was designed and analyzed,the operating timing of the AD chip was analyzed and the FPGA string and conversion and signal observation logic was designed.This design adopts a dual-sampling fully differential signal acquisition circuit,the sampling rate is designed to be 1MSPS,the resolution is 16 bit.It has the characteristics of large dynamic range,small distortion,and resistance to common-mode interference.Finally,a test platform was built to test the power supply,voltage follower and analog-to-digital conversion function module.The results showed that all the indicators of the short-wave infrared camera data acquisition system meet the requirements.