神龙一号参数测量用高速两分幅相机

High-speed two-frame gated camera for parameters measurement of Dragon-Ⅰ LIA

采用长焦距镜头的后工作空间全口径分光原理,利用门控型像增强器、CCD相机、基于大规模可编程集成电路的高速快门控制触发系统等部件,研制了具有较高时间分辨能力和高灵敏度的两分幅高速相机,并在此基础上建立了束参数的高速测量系统。两分幅相机的最高快门速度约3ns,幅间间隔时间则具有以0.5ns的步进进行调节的能力;快门时间及幅间间隔时间可以分别独立调节,最大可到1s;同时具有较好的线性度和空间响应的均匀性,等效背景噪声低到约5electrons.pixel-1.s-1,并且分幅相机灵敏度调节范围大。该系统一次可以拍摄两幅图像,图像阵列可达到1 024×1 024,满足神龙一号的各种测量要求。

The time-resolved measurement system which can work at very high speed is necessary in electron beam parameter diagnosis for Dragon-Ⅰ linear induction accelerator（LIA）.A two-frame gated camera system has been developed and put into operation.The camera system adopts the optical principle of splitting the imaging light beam into two parts in the imaging space of a lens with long focus length.It includes lens coupled gated image intensifier,CCD camera,high speed shutter trigger device based on large scale field programmable gate array.The minimum exposure time for each image is about 3 ns,and the interval time between two images can be adjusted with a step of about 0.5 ns.The exposure time and the interval time can be independently adjusted and can reach about 1 s.The camera system features good linearity,good response uniformity,equivalent background illumination（EBI） as low as about 5 electrons per pixel per second,large adjustment range of sensitivity,and excellent flexibility and adaptability in applications.The camera system can capture two frame images at one time with the image size of 1 024×1 024.It meets the requirements of measurement for Dragon-Ⅰ LIA.