| 摘要 |
PURPOSE:To achieve an easy and quick calibration of an equipment by regulating the voltage applied on an X ray tube with a calibration plate having an Al foil and a Ti foil so that the ratio of individual X ray absorprion coefficient may reach a specified value. CONSTITUTION:Circular Al and Ti foils 61 and 62 are buried into a calibration plate 6 and a notch section 63 is formed thereon. When a selector switch provided on a driver section 7 is turned to the position of 'measurement', a notch section 63 of the calibration plate 6 is provided in a path of X ray 4 and the damping level of X ray 4 from material 2 to be measured is detected with a dtector 3 whereby the content by weight of ash contained therein 2 is determined. Then, after the removal of the material 2, when the selector switch is turned to the position of 'calibration', the Al foil 61 on the calibration plate 6 and the Ti foil 62, a certain time later, are set into the path of X ray 4 to detect the current intensity of the X ray. Both detection signals are computed with an arithmetic processing circuit 5 to regulate the voltage applied on an X ray tube 1 for the ratio of the signals to reach the specified value. |
