High-sensitive radiography system utilizing a pulse x-ray generator and a night-vision CCD camera (MLX)

摘要

High-sensitive radiography system utilizing a kilohertz-range stroboscopic x-ray generator and a night-vision CCD camera (MLX) is described. The x-ray generator consists of the following major components: a main controller, a condenser unit with a Cockcroft-Walton circuit, and an x-ray tube unit in conjunction with a grid controller. The main condenser of about 500 nF in the unit is charged up to 100 kV by the circuit, and the electric charges in the condenser are discharged to the triode by the grid control circuit. The maximum tube current and the repetition rate are approximately 0.5 A and 50 kHz, respectively. The x-ray pulse width ranges from 0.01 to 1.0 ms, and the maximum shot number has a value of 32. At a charging voltage of 60 kV and a width of 1.0 ms, the x-ray intensity obtained without filtering was 6.04 μGy at 1.0 m per pulse. In radiography, an object is exposed by the pulse x-ray generator, and a radiogram is taken by an image intensifier. The image is intensified by the CCD camera, and a stop-motion image is stored by a flash memory device using a trigger delay device. The image quality was improved with increases in the x-ray duration, and a single-shot radiography was performed with durations of less than 1.0 ms.