The point target detection system is a detection and measurement system that ensures high signal to noise ratio for weak targets and can simultaneously detect targets of different intensities,achieving high sensitivity detection over a large dynamic range.Traditional imaging systems cannot simultaneously balance signal to noise ratio and dynamic range by switching the detector′s integrating capacitance and changing the integrating time.For the scanning infrared point target detection system using linear TDI infrared detectors,this paper comprehensively considers the radiant intensity of weak targets and background clutter,and proposes that the infrared detector adopts the TDI accumulation uneven scheme to improve the signal to noise ratio of the camera,as well as the image signal to noise ratio,so as to improve the weak target detection ability.At the same time,a TDI accumulation output and single pixel output automatic selection scheme is proposed to solve the problem of system dynamic range reduction caused by uneven accumulation.Based on the observation image requirements,a method for normalizing the output response of the detection system was proposed.Finally,the correctness of the system design method was verified through experimental testing.