Patent ID: 7919921

Claim:
A photomultiplier, comprising: a housing whose internal space, defined by an inner wall surface including a device mounting surface, is maintained in a vacuum state; a photocathode, accommodated in the internal space of said housing, emitting electrons to an inside of said housing in response to light taken in via said housing; an electron-multiplier section, accommodated in the internal space of said housing while being disposed on the device mounting surface, said electron-multiplier section having dynodes at multiple stages sequentially disposed on the device mounting surface along an electron traveling direction; an anode, accommodated in the internal space of said housing while being disposed on the device mounting surface, said anode taking out, as signals, electrons having reached among electrons cascade-multiplied in said electron-multiplier section; and a voltage distributing section, accommodated in the internal space of said housing, applying a predetermined voltage to each of the dynodes at multiple stages constituting said electron-multiplier section, said voltage distributing section being disposed on the device mounting surface together with said electron-multiplier section and said anode while being separated from the inner wall of said housing excluding the device mounting surface.