一种冷阴极电子枪的模拟研究

Design and Research of a Cold Cathode Electron Gun

文章通过Computer Simulation Technology粒子工作室软件建立了一种电子通过率极高的微焦点冷阴极电子枪。重点研究了电子枪自身结构对焦点、电子通过率和阴极发射电流的影响。特别是仿照了皮尔斯电子枪的结构,采用了一种弧面阴极,并在此基础上增加了一个阴极凹槽,使电子通过率从75.21%提高到90.26%,同时将近500μm的焦点缩小到50μm以内。最终设计出的冷阴极电子枪在阳极电压为90 kV且栅极电压为1 kV的条件下,电子通过率可达95.41%,在阳极靶面得到的束斑有效焦点尺寸约为45μm。

In this paper,a kind of micro-focus cold cathode X-ray tube with a very high electron passing rate is established by using Computer Simulation Technology Particle Studio software.The effect of X-ray tube structure on focal point,electron passing rate,and cathode emission current is studied emphatically.In particular,following the structure of the Pierce electron gun,a curved is adopted,and a cathode groove is added on this basis,so that the electron passing rate is increased from 75.21%to 90.26%,while the focus of nearly 500μm is reduced to less than 50μm.Under the condition that the anode voltage is 90 kV and the gate voltage is 1000 V,the electron pass rate of the cold cathode electron gun can reach 95.41%,and the effective focus size at the anode target surface is about 45μm.