| 摘要 |
<p>PURPOSE:To effectively make use of incident light to a dead space formed among a plurality of photoelectron multiplier tubes or at the end sections of photoelectron multiplier tube groups. CONSTITUTION:Plural ones out of a number of photoelectron multiplier tubes 2 are two dimensionally lined up, and a light guide 2 and a scintillator 5 are disposed in front of the multiplier tubes. A photoelectron surface 7 and a side tube photoelectron surface 7a are formed in the inner surface of the end section of each photoelectron multiplier tube 2 and in the inner surface of a side tube, and a Al deposition film 13 to be coated over the inner surface of the side tube, is formed at a place which is a little lower than the aforesaid inner surface of the tube end section. A reflection mirror 14 roughly in a triangular cone shape is disposed in each cavity, that is, a dead space 9 formed among the respective photoelectron multiplier tubes 2, so that light coming in the dead space 9 is reflected by the reflection mirror 14 so as to be incident light to the photoelectron surface 7a of the side tube section.</p> |
