| 摘要 |
PURPOSE:To measure intensities of X rays beam more than 50% and under 50% in the absorption rate simultaneously, by providing a means for detecting fluorescence from a scintillator at the right angle to the optical axis of X rays incident with the X rays absorption rate of 50% or less so as to allow the transmission of X rays other than these absorbed by the scintillator. CONSTITUTION:A case 10 of a detector is provided with openings 10a and 10b so as not to block incident incident X rays 1 and transmission X rays 2 and the openings are covered with an an X-ray beryllium plate 4. A plastic scintillator 3 is mounted on an photoelectric multiplier 6 through an optical coupler 5. Then, it so arranged that fluorescene is taken out at the right angle of the incident X rays 1 and the transmission X rays 2 to avoid the multiplier 6 for detecting fluorescence over the optical path of X rays. After an output pulse of the multiplier 6 is amplified with an amplifier 7, the output pulse alone is selected with a pulse height discriminator 8 depending on the X rays of energy as desired to be counted with a counter 9. This enables simultaneous measurement of the intensities of X rays beams with the absorption rates of more than 50% and under 50%. |
