【作者】 张震； 程湘爱； 江天； 邱冬冬； 姜宗福；

【Author】 ZHANG Zhen,CHENG Xiang-ai,JIANG Tian,QIU Dong-dong,JIANG Zong-fu(College of Optoelectronic Science and Engineering,National University of Defense Technology Chang Sha 410073,China)

【机构】 国防科学技术大学光电科学与工程学院；

【摘要】 在重频脉冲激光辐照可见光面阵CCD相机的实验中发现,某些入射到CCD相机光敏面上的激光脉冲未在CCD输出视频中的相应位置形成主光斑,我们将该现象称为主光斑丢失。通过分析与检测发现,电子快门使CCD相机的有效积分时间在时间轴上按一定占空比呈周期性脉冲序列分布。一个积分时间脉冲对应着一场图像的有效积分时间。在有效积分时间之外入射的激光脉冲所产生的信号将会被清空;只有在有效积分时间内入射的激光脉冲才能形成输出图像中的光斑。故只有当激光脉冲间隔时间小于有效积分时间时,才能保证每场图像中都有激光主光斑的存在。但CCD相机有效积分时间通常会根据入射光通量由电子快门脉冲自动调节,即光通量越大,有效积分时间占空比越小,故在高重频激光脉冲入射时,主光斑丢失的现象仍然存在。更多还原

【Abstract】 In the experiment of repetition laser irradiating the visible light CCD camera,we find that some laser pulses that have irradiated the sensor don’t cause the corresponding spots in the output video of visible light CCD camera.This phenomenon is named as disappearing of main spots.This article analyzes and detects its reason.The electronic shutter makes the effective integral time a periodic pulse sequence that has a fill factor in time axis.A integral time pulse is a effective integral time of a frame.Only the laser pulse irradiates the CCD sensor during the integral time pulse,can its signal be collected.Otherwise,its signal would be cleared by electronic shutter pulse.And then,only the interval of laser pulse is shorter than a integral time pulse,can every field picture has a main spots of laser.The integral time pulse of CCD usually accommodate automatically along with luminous flux according to inverse proportion.So in despite of the irradiating laser has a high repetition,the disappearing of main spots exists all the same.更多还原