PHOTOCATHODE, ELECTRON TUBE, AND PHOTOMULTIPLIER TUBE

摘要

PROBLEM TO BE SOLVED: To provide: a photocathode capable of improving effectual quantum efficiency; an electron tube having the photocathode; and a photomultiplier tube.;SOLUTION: In the photocathodes 1A, 1B, a base layer 200 consisting of a crystalline material containing La₂O₃ is installed between support substrates 100A, 100B and a photoelectron emitting layer 300, and is in contact with the photoelectron emitting layer 300. Thus, for example, at the time of heat treatment in a manufacturing step of the photocathodes 1A, 1B, diffusion of alkali metal contained in the photoelectron emitting layer 300 to the support substrates 100A, 100B side is suppressed. Furthermore, this base layer 200 is presumed to be functioning to reverse the advancing direction of photoelectrons going to the support substrates 100A, 100B side out of the photoelectrons e^- generated in the photoelectron emitting layer 300 to the opposite side.;COPYRIGHT: (C)2011,JPO&INPIT