光学学报, 2017, 37 (5): 0523001, 网络出版: 2017-05-05
单一视角X射线分幅变像管设计
Design of X-Ray Framing Camera with Single Perspective
光学器件 分幅相机 超快光学 微通道板选通 变像管 optical devices framing camera ultrafast optical gated micro channel plate tube
摘要
针对传统X射线快门选通微通道板(MCP)分幅相机利用针孔阵列获取目标图像时视角不一致的问题, 提出一种单一视角X射线变像管分幅方法。利用电子束团在电子光学交叉点所携带信息的全息性和可分割性, 设计了一种单一视角多幅输出图像的静电聚焦变像管, 输出端配接MCP分幅单元以实现图像选通和增强功能。与传统门控MCP分幅管相比, 其既能实现图像视角的同一性, 又可以避免直穿光激发荧光屏对输出图像的影响, 具有更高的信噪比。所设计的分幅变像管阴极有效工作直径为40 mm, 输出荧光屏直径为40 mm, 放大倍率为1.29, 中心理论空间分辨率达到60 lp/mm, 边缘空间分辨率达到26 lp/mm, 分幅曝光时间特性由快门选通MCP分幅单元的选通脉宽决定。该方法为实现X射线分幅相机视角同一性给出了一条有效途径。
Abstract
In view of the inconsistent perspective in target images obtained by pinhole array for traditional X-ray gating micro channel plate (MCP) framing camera, an implement method of X-ray framing camera with single perspective is proposed. At the electro-optic intersection in electrostatic focus image tube, the electrons carry holographic information, and can be divided into multiple output images with single perspective, subsequently a gated MCP unit is matched with the frame to enhance the target image. Compared with the traditional gated MCP framing camera, the designed framing camera realizes identity of image perspective and avoids direct light′s excitation on screen, and a higher signal-to-noise ratio is obtained. The designed framing image tube has an effective input working diameter of 40 mm, an output image diameter of 40 mm, a magnification of 1.29, the center spatial resolution of 60 lp/mm in theory, the marginal spatial resolution of 26 lp/mm, and the geometric distortion of less than 15%. Single frame exposure duration is determined by shutter pulse time of gated MCP framing unit. This method is an effective way to realize identity of image perspective for X-ray framing image camera.
宗方轲, 张敬金, 雷保国, 郭宝平, 杨勤劳. 单一视角X射线分幅变像管设计[J]. 光学学报, 2017, 37(5): 0523001. Zong Fangke, Zhang Jingjin, Lei Baoguo, Guo Baoping, Yang Qinlao. Design of X-Ray Framing Camera with Single Perspective[J]. Acta Optica Sinica, 2017, 37(5): 0523001.