Compact glow discharge x-ray tube

We have developed a compact glow discharge x-ray tube (diameter: 10 mm, length: 20 mm), which is composed of a hollow anode tube, a cathode plate, and a thin film target. This glow discharge device was operated with an Al thin film target at a discharge voltage of 2.0 kV at a discharge current of 0.1 mA and at a He pressure of approximately 0.2 Torr, which was used as the discharge gas. The characteristic x rays of Al K alpha are produced by bombardment of electrons emitted from the cathode surface. The strong x-ray emission intensity, which depended on the operating voltage and the gas pressure, was obtained throughout the discharge time of 1.5 h. (C) 1998 American Institute of Physics. [S0034-6748(98)03811-8].