Claims
- 1. In a gamma-insensitive sensor comprising a cathode and an anode separated by a gap containing a gas and means for applying an electric potential between the anode and the cathode thereby producing an electric field in the gap, the improvement comprising:
- a buffer assembly positioned intermediate said cathode and said anode for preventing chemical incompatibility between materials constituting the cathode and the composition of the gas within the gap.
- 2. The improvement of claim 1, wherein said buffer assembly comprises a honeycomb-like support structure, and a barrier film of material transparent to electrons passing from the cathode to the anode.
- 3. The improvement of claim 2, wherein said honeycomb-like support structure is under a vacuum.
- 4. The improvement of claim 2, wherein said honeycomb-like support structure is constructed from any insulating material providing adequate support to the barrier film, so as to provide acceptable barrier film-to-anode gap uniformity.
- 5. The improvement of claim 4, wherein said honeycomb-like support structure is constructed of glass with a uniform distribution of circular pores having diameters of greater than 12.mu. and pore center-to-center spacings of greater than 15.mu., and has a thickness in the range of 0.5 mm to 2 mm.
- 6. The improvement of claim 5, wherein said pore diameters are in the range of 12.mu. to 30.mu., and wherein said pore center-to-center spacings are in the range of 15.mu. to 40.mu..
- 7. The improvement of claim 2, wherein said barrier film is constructed from conducting material that can be produced as a thin film.
- 8. The improvement of claim 7, wherein said barrier film has a thickness of 0.05.mu. to 0.2.mu..
- 9. The improvement of claim 7, wherein said barrier film is constructed from the group of aluminum and beryllium and has a thickness of 1000 .ANG..
- 10. The improvement of claim 1, additionally including means for applying a voltage across said honeycomb-like structure.
- 11. A gamma-insensitive sensor comprising:
- a cathode;
- an anode;
- said cathode and said anode being separated to form a gap there between;
- a buffer assembly positioned between said cathode and said anode and located adjacent said cathode;
- said anode including a plurality of anode pads defining a pattern;
- said gap containing a gas;
- means for applying an electric potential between the anode and the cathode for producing an electric field there between; and
- means for detecting electron avalanche charges on said anode pads.
- 12. The sensor of claim 11, wherein said buffer assembly prevents chemical incompatibility between materials of said cathode and composition of said gas, and comprises a honeycomb-like structure and a barrier membrane transparent to electrons passing from the cathode to the anode pads.
- 13. The sensor of claim 12, wherein said honeycomb-like structure of said buffer assembly is under a vacuum.
- 14. The sensor of claim 12, wherein said honeycomb-like structure is constructed of material selected from the group consisting of glass, and other insulating material.
- 15. The sensor of claim 14, wherein said barrier membrane is constructed of material selected from the group consisting of aluminum, beryllium, and other conducting material or non-conducting material coated with a conducting material.
- 16. The sensor of claim 15, wherein said barrier membrane has a thickness of about 0.05.mu. to about 0.2.mu..
- 17. The sensor of claim 16, wherein said honeycomb-like structure has pore sizes of about 12.mu. to about 30.mu., pore center-to-center spacings of about 15.mu. to about 40.mu., and a thickness of about 0.5 mm to about 2 mm.
- 18. The sensor of claim 17, wherein said honeycomb-like structure is constructed of glass, wherein said barrier membrane is constructed from aluminum or beryllium, and wherein said honeycomb-like structure is under a vacuum.
- 19. The sensor of claim 18, wherein said honeycomb-like structure has a thickness of about 1 mm, wherein said barrier membrane has a thickness of about 1000 .ANG., and wherein said vacuum in said honeycomb-like structure is about 150-200 torr.
- 20. An optical focal plane array, comprising:
- a planar monolithic quartz cathode plate;
- a semi-transparent photocathode layer disposed over a planar surface of the quartz plate;
- a planar monolithic anode plate, positioned parallel to the photocathode layer and separated therefrom by a narrow gap, with a first planar surface of the anode plate being closer to the photocathode layer than a second planar surface of the anode plate;
- a pixel array of anode pads disposed upon the first planar surface of the anode plate;
- a pixel array of contact pads disposed upon the second planar surface of the anode plate;
- means for electrically connecting each anode pad to a corresponding contact pad;
- a gas positioned within the narrow gap;
- a buffer assembly positioned between said photocathode layer and said gas to prevent chemical incompatibility there between; and
- means for impressing a voltage between the anode pads and the photocathode layer.
Government Interests
The U.S. Government has rights in this invention pursuant to Contract No. W-7405-ENG-48 between the U.S. Department of Energy and the University of California for the operation of Lawrence Livermore National Laboratory.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
3961182 |
Spicer |
Aug 1972 |
|