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AssigneeHamamatsu Photonics K.K.
InventorsTakayuki Ohmura, Suenori Kimura, Masuo Ito
Estimating the term…
The present invention relates to a photomultiplier having a structure that enables to perform high gain and satisfy higher required characteristics. In the photomultiplier, an electron-multiplying unit accommodated in a sealed container comprises a focusing electrode, an accelerating electrode, a dynode unit, and an anode. Particularly, at least the accelerating electrode and dynode unit are held unitedly in a state that at least a first-stage dynode and a second-stage included in the dynode unit are opposite directly to the accelerating electrode not through a conductive material. A conventional metal disk for supporting directly dynodes which are set to the same potential as that of the first-stage dynode is not placed between the accelerating electrode and dynode unit; thus, variations of the transit time of electrons may be drastically reduced while the electrons reach from the cathode to the second-stage dynode via the first-stage dynode.
A photomultiplier comprising:
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Electron multipliers: electrode arrangements
Electric discharge tubes or discharge lamps
Term ended 12 Aug 2026 (estimated)
1. Field of the Invention
The present invention relates to a photomultiplier that enables a cascade-multiplication of secondary electrons by emitting sequentially the secondary electrons through a plurality of stages in response to incidence of photoelectrons.
2. Related Background Art
FIG. 1 is a partially cutaway view illustrating a schematic structure of a first embodiment of the photomultiplier according to the present invention;
FIG. 2 is a view illustrating a cross-sectional structure of the photomultiplier according to the first embodiment, taken along the line I-I depicted in FIG. 1;
FIG. 3 is an assembly process view for explaining the construction of an electron-multiplying unit adapted to the photomultiplier according to the first embodiment;
In the following, embodiments of a photomultiplier according to the present invention will be explained in detail with reference to FIGS. 1-12, 13A-14B and 15. In the explanation of the drawings, constituents identical to each other will be referred to with numerals identical to each other without repeating their overlapping descriptions.
FIG. 1 is a partially cutaway view illustrating a schematic structure of a photomultiplier of an embodiment according to the present invention.
As shown in FIG. 1, a photomultiplier 100 includes a sealed container 110 provided with a pipe 130 (solidified after evacuation) for evacuating the inside at the bottom thereof, a cathode 120 provided in the sealed container 110 and an electron-multiplying unit.