Patent ID: 7855510
Filing Date: 2010-12-21
Classification: H01J

Abstract:
1. A photomultiplier tube comprising: a cathode emitting electrons in response to incident light; a plurality of dynodes multiplying electrons emitted from the cathode, each dynode extending in a prescribed direction, the plurality of dynodes having a first dynode and a second, dynode, the first dynode receiving electrons from the cathode and multiplying the electrons and emitting the multiplied electrons, and the second dynode receiving the electrons from the first dynode and multiplying the electrons and emitting the multiplied electrons, the first dynode having a first end face and a second end face opposite the first end face, the first end face and the second end face extending perpendicularly to the prescribed direction and the second dynode having a first end and a second end; and potential regulating means smoothing an equipotential surface in a space between the first dynode and the second dynode along the prescribed direction, the potential regulating means including a first regulating element and a second regulating element that is separate from the first regulating element, the first regulating element being located between the first end face of the first dynode and the first end of the second dynode in a direction perpendicular to the prescribed direction and the second regulating element being located between the second end face of the first dynode and the second end of the second dynode in the direction perpendicular to the prescribed direction.