| 摘要 |
A photomultiplier tube includes a photocathode (4), a focusing electrode (7), a dynode array (8), and an anode (9), all contained within a vacuum sealed container (1). The container (1) is configured from a glass bulb having a transparent portion (2) on which light is incident and which guides the light to the photocathode (4) and a colored portion (11) which is colored black. In this configuration, even if cosmic rays or ambient gamma rays or leakage electrons from inside the dynode array (8) generate light in the side wall of the glass bulb (1), the light will be absorbed or trapped in the colored portion (11). Therefore, light which becomes a source of noise will not reach the photocathode (4). <IMAGE> |
