| 摘要 |
PURPOSE:To detect a fault of a photoelectric multiplier easily and exactly, by separately placing an element which emits light by a test pulse, in the vicinity of plural photoelectric multipliers which are used for a plastic scintillator. CONSTITUTION:A scintillation detector is constituted of plural photoelectric multipliers 1 (4 pieces in case of the figure) which are used for making a sensitivity distribution characteristic uniform, a plastic scintillator 2, a light shielding film 3, a reflecting plate 4 and a case 5. In the vicinity of a photoelectric surface 1a, a luminous body 11 such as a light emission diode, etc. having a directivity by a test pulse generated by a pulser 10 is placed separately. A falut is detected through an amplifier 8 and a deciding circuit 9 by irradiating in order the photoelectric multipliers 1. It is also available to irradiate the photoelectric surface 1a separately by an optical fiber from the outside without placing the luminous body in the case. In this regard, even when the photoelectric multiplier is checked by turning it on and off, the same result is obtained. In this way, the photoelectric multiplier is checked exactly and easily as it remains mounted. |
