Photomultiplier

• US 20090045741A1
• Filed: 06/01/2006
• Published: 02/19/2009
• Est. Priority Date: 08/10/2005
• Status: Active Grant

• Current Assignee: Hamamatsu Photonics KK
• Original Assignee: Hamamatsu Photonics KK
• Inventors: Ohmura, Takayuki, Kimura, Suenori, Kishita, Hitoshi, Masuda, Yuji, Sugiyama, Hiroyuki, Kyushima, Hiroyuki, Shimoi, Hideki
• Granted Patent: US 7,880,385 B2
• Time in Patent Office: Days
• US Class Current: 313/532
• CPC Class Codes: H01J 43/24 Dynodes having potential gradient along their surfaces

Abstract

The present invention relates to a photomultiplier having a fine structure capable of realizing high detection accuracy by effectively suppressing cross talk among electron-multiplier channels. The photomultiplier comprises a housing whose inside is maintained vacuum, and, in the housing, a photocathode, an electron-multiplier section, and anodes are disposed. The electron-multiplier section has groove portions for cascade-multiplying photoelectrons as electron-multiplier channels, and the anodes are constituted by channel electrodes corresponding to the groove portions respectively defined by wall parts. In particular, at least parts of the respective channel electrodes are located in spaces sandwiched between pairs of wall parts defining the corresponding groove portions.

Claims

1. :

A photomultiplier, comprising;

a housing whose inside is maintained in a vacuum state;

a photocathode, accommodated in said housing, emitting electrons to the inside of said housing in response to light taken in via said housing;

an electron-multiplier section, accommodated in said housing, having groove portions extending along an electron traveling direction; and

anodes, accommodated in said housing, taking out, as signals, electrons having reached among electrons cascade-multiplied in said electron-multiplier section, said anodes being constituted by a plurality of channel electrodes which are provided to respectively correspond to the groove portions in said electron-multiplier section and whose at least parts are located in spaces sandwiched between pairs of wall parts defining corresponding groove portions.

2. :

A photomultiplier according to claim 1, wherein said respective channel electrodes constituting said anodes have protruding portions whose tips are inserted in the spaces sandwiched between the pairs of wall parts defining the corresponding groove portions.

5. :

A photomultiplier according to claim 2, wherein said respective channel electrodes constituting said anodes are fixed to parts of said housing with main body portions, and the protruding portions are supported by the main body portions so as to be spaced by a predetermined distance from said housing.

6. :

A photomultiplier according to claim 1, wherein said respective channel electrodes constituting said anodes are comprised of silicon.

3. :

A photomultiplier, comprising;

a housing whose inside is maintained in a vacuum state;

a photocathode, accommodated in said housing, emitting electrons to the inside of said housing in response to light taken in via said housing;

an electron-multiplier section, accommodated in said housing, having a plurality of through-holes extending along an electron traveling direction; and

anodes, accommodated in said housing, taking out, as signals, electrons having reached among electrons cascade-multiplied in said electron-multiplier section, said anodes being constituted by a plurality of channel electrodes which are provided to respectively correspond to the plurality of through-holes in said electron-multiplier section and whose at least parts are located in spaces sandwiched between wall parts defining corresponding through-holes.

4. :

A photomultiplier according to claim 3, wherein said respective channel electrodes constituting said anodes have protruding portions whose tips are inserted in the spaces sandwiched between the wall parts defining the corresponding through-holes.

7. :

A photomultiplier according to claim 4, wherein said respective channel electrodes constituting said anodes are fixed to parts of said housing with main body portions, and the protruding portions are supported by the main body portions so as to be spaced by a predetermined distance from said housing.

8. :

A photomultiplier according to claim 3, wherein said respective channel electrodes structuring said anodes are comprised of silicon.