采样时间对光子计数图像的影响

Impact of Sampling Time on Photon Counting Image

夜暗环境下,为了弥补人眼在能量、光谱和分辨能力等方面的局限性,利用雪崩光电二极管作为探测元件构建了光子计数成像平台。借助该平台设置环境照度为10-4lx,采样时间分别取10 ms、2.6 ms和780μs,探测到了目标采样点的光子数,从而得到了三组反映目标特征的光子计数图像序列。根据对探测目标判断的程度,应用多帧累加处理方法,可以在保证成像平台具有较高帧频的条件下,选择合适的累加帧数以实现对目标不同等级的探测。

In order to compensate for the human visual limitations in energyspectrum and resolution under weak light environmentthe avalanche photodiode （APD） was used to establish a photon counting imaging experimental platform.Under the condition that the set ambient light illumination was 104 lxthe sampling periods were respectively 10 ms2.6 ms and 780 μsthree groups of the photon counting image sequenceswhich could demonstrate the target characteristicswere obtained.The technique of multiframe accumulation was applied to the target detection according to the different detection requirements.The appropriate number of the frames can be selected to ensure higher frame frequency.