应用于激光等离子体实验的脉冲展宽分幅相机

Development of pulse-dilation framing camera for laser-plasma experiment

研制基于脉冲展宽技术的行波选通X射线分幅相机,光电阴极加载偏置-3 kV的直流电压和斜率2.7 V/ps的斜坡电脉冲,微通道板微带上加载-483 V的直流偏置电压和半高宽度290 ps的选通电脉冲,电子图像成像比例为1∶1.利用激光器轰击金靶材产生短X射线均匀照明相机微带阴极,测得相机时间分辨率约为20 ps,在微带阴极长度小于20 mm范围内,相机增益均匀性优于20%;采用直流紫外光对相机的静态空间特性进行标定,在相机成像面直径小于56 mm范围内,空间分辨率测量值为10 lp/mm.

We develop a traveling wave gated X-ray framing camera based on electron beam pulse-dilation technology.The photocathode is loaded with a direct current(DC)bias of-3 kV and a widening pulse with a slope of 2.7 V/ps,and the microchannel plate biased at-483 V superimposed a negative high voltage gated pulse with full width at half maximum(FWHM)of 290 ps.The imaging ratio of the camera is 1∶1.Laser acts on a gold target to generate X-rays for uniform irradiation on the cathode.The temporal resolution of the camera is 20 ps and the gain uniformity of 20 mm cathode strip is better than 20%.The measured value of spatial resolution through a DC ultraviolet light source is 10 lp/mm in the range of imaging surface with a diameter of 56 mm.