First-stage dynode and photomultiplier tube
AssigneeHamamatsu Photonics K.K.
InventorsYuki Nishimura, Masahiro Kotani, Takanori Ichinomiya
Life of this patent
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Abstract
A first-stage dynode is a first-stage dynode to be used in a photomultiplier tube, and includes a bottom wall portion and a pair of side wall portions extending from both end portions of the bottom wall portion in a predetermined direction to one side. An electron emission surface is formed by a bottom surface of the bottom wall portion on the one side and a pair of side surfaces of the pair of side wall portions on the one side, and each of the pair of side surfaces is a curved surface that is curved in a concave shape in a cross section parallel to the predetermined direction.
Claims5
A first-stage dynode to be used in a photomultiplier tube, comprising:
- a bottom wall portion;
- and
- a pair of side wall portions extending from both end portions of the bottom wall portion in a predetermined direction to one side,
- wherein an electron emission surface is formed by a bottom surface of the bottom wall portion on the one side and a pair of side surfaces of the pair of side wall portions on the one side,
- each of the pair of side surfaces is a curved surface that is curved in a concave shape in a cross section parallel to the predetermined direction, and
- assuming that a width of the electron emission surface in the predetermined direction is L and a radius of curvature of each of the pair of side surfaces is R, R≥0.1L is satisfied.
A photomultiplier tube, comprising:
- a photocathode;
- a plurality of stages of dynodes;
- and
- an anode,
- wherein the plurality of stages of dynodes include a first-stage dynode and a second-stage dynode arranged on a predetermined plane,
- the first-stage dynode includes:
- a bottom wall portion;
- and
- a pair of side wall portions extending from both end portions of the bottom wall portion in a predetermined direction to the photocathode side and the second-stage dynode side, the predetermined direction being perpendicular to the predetermined plane,
- in the first-stage dynode, an electron emission surface is formed by a bottom surface of the bottom wall portion on the photocathode side and the second-stage dynode side and a pair of side surfaces of the pair of side wall portions on the photocathode side and the second-stage dynode side,
- each of the pair of side surfaces is a curved surface that is curved in a concave shape in a cross section parallel to the predetermined direction, and
- assuming that a width of the electron emission surface in the predetermined direction is L and a radius of curvature of each of the pair of side surfaces is R, R≥0.1L is satisfied.
Dependencies are inferred from the claim text.