Development of the Flash X-ray Generators and their Applications to High-Speed Biomedical Radiography

Abstract

  Development of Various flash x-ray generators and their applications to high-speed biomedical radiography are described. Six types of high-voltage pulsers are as follows : 1. a single-pulse generator having a gas gap used for the diode tube, 2. a single-pulse generator utilizing a gas gap used for the triode tube, 3. a repetitive pulser for the diode tube with a repetitive frequency of less than 50 Hz, 4. a repetitive pulser for the triode tube with a frequency of less than 100Hz, 5. a triple-shot type having a single diode, and 6. a triple-shot type utilizing three diodes. These pulsers, in conjunction with the x-ray tubes, may be used for output voltages of less than 150kV (tube voltage), and peak currents of less than 40 kA. The flash x-ray intensity was primarily determined by controlling the condenser charging voltage and the anode-cathode (A-C) space and was reduced by insertion of metal filters. The x-ray quality became hard according to increase m the charging voltage, insertion of metal filters, and other factors. The effective focal spot sizes were determined by the diameters of anode rods, and their sizes were less than 3.0mm in diameter. These generators in conjunction with various types of timing switches for producing the starting pulses for the delayed pulse generator have many future possibilities for performing biomedical radiography utilizing their high-speed capabilities.