Photomultiplier
AssigneeHamamatsu Photonics K.K.
InventorsTomohiro Ishizu, Suenori Kimura
Life of this patent
Estimating the term…
Abstract
A photomultiplier tube excellent in vibration resistance and having an anode with good pulse linearity characteristic. The photomultiplier tube has a mesh anode (A) composed of an anode frame (A11) and a mesh electrode (A12) supported and surrounded by the anode frame (A11). The central portion of one long side (A11B) of the anode frame (A11) serves as an electron converging part (F). The inner side of the anode frame (A11) swells toward the inner part of the anode (A), more from the middle of the long side (A11B) toward the corners of the anode frame (A11) along the long side (A11B), and therefore the thickness of the anode frame (A11) increases from the middle of the long side (A11) to the corners along the long side (A11B).
Claims6
A photomultiplier tube comprising:
- a tube-shaped vacuum vessel (2) extending along a tube axis (X);
- a photocathode (2A) positioned on one end of the tube-shaped vacuum vessel (2) in the tube axis, for converting incident light to electrons;
- a plurality of dynodes arranged in n stages (Dy1-Dy10) each having a secondary electron emitting surface formed on an inner wall thereof, for multiplying electrons sequentially;
- an anode (A) for receiving the electrons multiplied by the plurality of dynodes (Dy1-Dy10), the anode including a mesh electrode (A12) and an anode frame (A11) for retaining the mesh electrode (A12),
- characterized in that the anode frame (A11) is substantially rectangular in shape wherein an electron converging part (F) at which electrons multiplied by the plurality of dynodes (Dy1-Dy10) converge is formed near a center part on one long side (A11A) of the anode frame (A11), and
- that inner surface (A11b, A11c, A21b, A31c, A41c) of the anode frame (A11) has a such a shape that is nearest to the one long side (A11A) of the anode frame (A11) at a center point of the one long side (A11A) and that is gradually farther from the one long side (A11A) with increased distance from the center point, so that the anode frame (A11) grows thicker on the one long side (A11A) with increased distance from the center point.
Dependencies are inferred from the claim text.