DYNODE ASSEMBLY FOR ELECTRON MULTIPLIER

• US 3,619,692 A
• Filed: 08/13/1969
• Issued: 11/09/1971
• Est. Priority Date: 08/13/1969
• Status: Expired due to Term

• Current Assignee: ITT Corporation (ITT, Inc.)
• Original Assignee: Cyril L. Day
• Inventors: Day, Cyril L.
• Primary Examiner(s): Segal, Robert
• Application Number:
  US04/849,675
• Time in Patent Office: 818 Days
• Field of Search: 313/103,105,104
• US Class Current: 313/105.00R
• CPC Class Codes: H01J 43/20 Dynodes consisting of sheet material, e.g. plane, bent

Abstract

A miniature electron multiplier having a pair of complementary dynode support elements formed of ceramic material, each of the elements having a plurality of longitudinally spaced-apart projections extending transversely outwardly from a side thereof and mutually defining outwardly facing recesses therebetween. The elements are disposed with their sides in spaced, parallel facing relationship with the projections of one element located generally midway between the projections of the other element and respectively extending toward the recesses of the other element but having their outer ends spaced from the side thereof so as to define a generally serpentine channel. A plurality of dynode elements formed of relatively thin sheet metal are respectively seated in the recesses and brazed to the walls thereof. Top and bottom plate elements formed of ceramic material secure the support elements in assembled relation and close the channel. The dynode elements have integral leads which extend outwardly between the respective support element and plate element to the exterior of the assembly where they may be attached to a voltage divider resistance printed upon the outer surface of one of the cover plates.

Claims

1. In an electron-multiplier device, a dynode assembly comprising:

a pair of complementary dynode support elements formed of dielectric material and respectively having longitudinally spaced opposite ends, each of said support elements having a plurality of longitudinally spaced-apart projections extending transversely outwardly from a side thereof and mutually defining outwardly facing recesses therebetween, said support elements being disposed with said sides in space, parallel, facing relationship and with the projections of one support element located generally midway between the projections of the other support element and respectively extending toward the recesses of the other support element but having their outer ends spaced from the side thereof thereby defining a generally serpentine channel between said opposite ends;

a plurality of discrete metallic dynode elements respectively seated in said recesses and engaging the walls thereof, the adjacent ends of the dynodes in said recesses on each said support element being spaced apart longitudinally; and

means for securing said support elements in assembled relation.

2. The assembly of claim 1 wherein said dynode elements are of relatively thin sheet metal, the walls of said recesses having a metallized coating thereon and said dynode elements being brazed thereto.

3. The assembly of claim 1 wherein each of said support elements has spaced, parallel top and bottom surfaces normal to the respective side, said top and bottom surfaCes being respectively coplanar when said support elements are in assembled relation, said securing means comprising top and bottom plate elements formed of dielectric material and respectively abutting said top and bottom surfaces and closing said channel, and fastener means for respectively securing said plate elements to said support elements.

4. The assembly of claim 1 further comprising a field-shaping electrode located in each of said recesses and having a lead extending through and supported by said securing means.

5. The assembly of claim 1 wherein there are two of said dynode elements in each of said recesses respectively extending from adjacent the outer end of a respective projection to adjacent the midpoint of the respective recess, said two dynodes having closely spaced adjacent edges.

6. The assembly of claim 5 wherein each of said support elements has a slot formed in its said side in a respective recess between the adjacent edges the respective two dynode elements.

7. The assembly of claim 1 wherein said support elements are formed of ceramic material, said dynode elements being formed of relatively thin sheet metal and being attached to the walls of said recesses;

each of said support elements having spaced, parallel top and bottom surfaces normal to the respective side, said top and bottom surfaces being respectively coplanar when said support elements are in assembled relation, said securing means comprising top and bottom plate elements formed of ceramic material and respectively abutting said top and bottom surfaces and closing said channel, and means for respectively securing said plate elements to said support elements;

each of said dynode elements having an integral lead extending therefrom outwardly between a respective surface and plate element to the exterior of said assembly.

8. The assembly of claim 1 wherein each of said recesses has a generally rectangular configuration.

9. The assembly of claim 1 including a transparent faceplate and photocathode enclosing one end of said channel and an output electrode at the other end.