Photomultiplier with lens element
AssigneeHamamatsu Photonics K.K.
InventorsHidehiro Kume, Suenori Kimura
Life of this patent
Estimating the term…
Abstract
A photomultiplier includes a photocathode (3); an electron multiplier section (60) for cascade-multiplying photoelectrons emitted from the photocathode (3); a faceplate (2) provided with the photocathode (3); a metal housing (1) accommodating the photocathode (3) and the electron multiplier section (60); and a structure disposed on the faceplate (2) for increasing the effective light entrance region of the faceplate (2). In a preferred embodiment the subject structure includes a lens element (30) attached to the faceplate for increasing the effective light entrance region of the faceplate (2). In order to improve the optical coupling efficiency, either the faceplate (2), or the lens element (30), or both the faceplate (2) and the lens element (30) may further include a protrusion.
Claims25
A photomultiplier comprising:
- a photocathode for emitting a photoelectron in response to incident light reaching said photocathode;
- an electron multiplier section for cascade-multiplying the photoelectron emitted from said photocathode;
- a faceplate having a mounted surface and a light receiving surface opposing said mounted surface, said mounted surface being provided with said photocathode;
- a metal housing extending along a predetermined center axis and accommodating said photocathode and said electron multiplier section, said metal housing having a flange which extends toward said center axis and supports said faceplate, said flange having an opening for defining an area of said light receiving surface of said faceplate;
- and
- a lens element provided on an opposite side to said electron multiplier section by way of said faceplate, said lens element having a convex surface projecting opposite to said faceplate, a coupling surface opposing said convex surface and facing said light receiving surface, and a protrusion projecting toward said light receiving surface of said faceplate and including said coupling surface.
A photomultiplier comprising:
- a photocathode for emitting a photoelectron in response to incident light reaching said photocathode;
- an electron multiplier section for cascade-multiplying the photoelectron emitted from said photocathode;
- a lens element provided on an opposite side to said electron multiplier section by way of said photocathode, said lens element having a convex surface projecting opposite to said photocathode, and a coupling surface opposing said convex surface and facing said photocathode;
- a metal housing extending along a predetermined center axis and accommodating said photocathode and said electron multiplier section, said metal housing having a flange which extends toward said center axis and has an opening for transmitting the incident light therethrough;
- and
- a faceplate having a mounted surface which is provided with said photocathode surface, and a light receiving surface opposing said mounted surface, said faceplate being supported by said flange of said metal housing and having a protrusion which projects toward said lens element and includes said light receiving surface, said light receiving surface being positioned between said coupling surface of said lens element and said photocathode.
A photomultiplier comprising:
- a photocathode for emitting a photoelectron in response to incident light reaching said photocathode;
- an electron multiplier section for cascade-multiplying the photoelectron emitted from said photocathode;
- a faceplate having a mounted surface and a light receiving surface opposing said mounted surface, said mounted surface being provided with said photocathode;
- a metal housing extending along a predetermined center axis and accommodating said photocathode and said electron multiplier section, said metal housing having a flange which extends toward said center axis and supports said faceplate, said flange having an opening for defining an area of said light receiving surface of said faceplate;
- and
- a structure disposed on said faceplate for making the area of an effective light entrance region become greater than the area of said light receiving surface defined by said opening of said flange, said effective light entrance region being on a plane in parallel with said light receiving surface and transmitting, of light advancing along a direction perpendicular to said light receiving surface, a predetermined light component therethrough, said predetermined light component reaching said light receiving surface.
Dependencies are inferred from the claim text.