| 摘要 |
PURPOSE:To obtain an improved direction characteristic regardless of a low- energy irradiation of radiation. CONSTITUTION:A first filter, for example, a tin filter 21a is placed in front-face direction of a fluorescent glass element. Also, a second filter with a different transmission from that of the first filter, for example, a copper filter 22 is placed in a direction which is vertical to the first filter, thus enabling direction characteristics for irradiation of low-energy radiation to be uniform.
|
