To provide an electron tube which can suppress the decay of light to be detected incoming to a transmission type photoelectric surface and detects slight light.
A mesa transmission-type photoelectric surface 30 is placed on a glass plate 10 while having a reflection preventing film 20 between them. The glass plate 10 is so supported in one end of a vacuum tube 11 as to set the transmission-type photoelectric surface 30 to face to the vacuum tube 11. A converging electrode 70 to converge photoelectrons (e-), a dynode part 71 to multiply the photoelectrons by secondary electrons, and an anode 40 are successively installed from the transmission type photoelectric surface 30 in the vacuum tube 11. Bias voltage VB is applied to the transmission type photoelectric surface 30 through stem pins 54a, b, electric leads 53a, b, a metal wire 52, a first electrode 50, and a second electrode 51. With this structure, light to be detected, which is a detection object, efficiently enter the transmission type photoelectric surface 30 without being decayed, photoelectrons are emitted more than those by a conventional method, and the signal current to be detected is also increased.
HIROHATA TORU
SUZUKI TOMOKO
SUGA HIROBUMI
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