Integrated coupling of scintillation crystal with photomultiplier in a detector apparatus

Patent metadata

Field	Value
Publication number	US-9880295-B2
Application number	US-201114355762-A
Country	US
Kind code	B2
Filing date	Oct 28, 2011
Priority date	Oct 28, 2010
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

A scintillator type radiation detector package is provided including a scintillation crystal directly coupled to the window of a photomultiplier. A scintillator package is also provided having a longer life at wellbore temperature with minimal deterioration of a hygroscopic scintillation crystal(s). Direct optical coupling of the scintillator to the photomultiplier reduces the amount of light lost at coupling interfaces and improved detection resolution over the conventional structures having separate packages for crystal and photomultiplier.

First claim

What is claimed is:

1. An apparatus comprising:
a scintillation radiation detector comprising:
a photomultiplier comprising:
a first housing; and
a faceplate;

a scintillation crystal directly contacting the faceplate;
a second housing encompassing the scintillation crystal and the faceplate; and
an intermediate flange connecting the first housing with the second housing, wherein the intermediate flange is located at an axial distance from the faceplate.

2. The apparatus of claim 1 wherein the second housing hermetically seals the scintillation crystal and faceplate.

3. The apparatus of claim 1 wherein the faceplate is connected directly to the second housing.

4. The apparatus of claim 1 wherein the photomultiplier further comprises:
a photocathode located on the faceplate opposite the scintillation crystal; and
a focusing electrode, wherein the intermediate flange is located closer to the focusing electrode than the photocathode.

5. The apparatus of claim 1 wherein the faceplate comprises a thickness, and wherein the axial distance is at least twice the thickness of the faceplate.

6. The apparatus of claim 1 wherein the intermediate flange comprises:
a first flange portion connected with the first housing;
a second flange portion connected with the second housing; and
a third flange portion directly or indirectly connected with the faceplate to maintain the faceplate against the scintillation crystal.

7. The apparatus of claim 6 wherein the third flange portion is located radially inwards from the second flange portion.

8. The apparatus of claim 1 wherein the scintillation radiation detector further comprises a faceplate flange disposed at least partially within the second housing, and wherein the faceplate flange extends between and connects the faceplate with the intermediate flange to maintain the faceplate against the scintillation crystal.

9. The apparatus of claim 1 wherein the first housing comprises glass, and wherein the intermediate flange comprises a metal ring connected with and extending around the first housing.

10. The apparatus of claim 1 wherein the first housing comprises a plurality of insulator rings electrically insulating a plurality of dynodes and/or focusing electrodes of the photomultiplier from each other, and wherein the intermediate flange is connected with at least one of the plurality of the insulator rings to electrically insulate the intermediate flange from an adjacent at least one of the plurality of dynodes and/or focusing electrodes.

11. The apparatus of claim 10 wherein the intermediate flange is connected with an end ring of the plurality of the insulator rings.

12. The apparatus of claim 10 wherein the intermediate flange comprises a side surface connected with a corresponding side surface of one of the plurality of the insulator rings.

13. The apparatus of claim 10 wherein the insulator rings each comprise a ceramic material or glass.

14. The apparatus of claim 1 wherein the photomultiplier further comprises:
an anode; and
a photocathode deposited on the faceplate, wherein the anode and photocathode are maintained at different electrical voltages, wherein the intermediate flange comprises metal, and wherein the photocathode and the second housing are maintained at the same electrical voltage.

15. The apparatus of claim 1 wherein the photomultiplier further comprises:
an anode; and
a photocathode deposited on the faceplate, wherein the anode and photocathode are maintained at different electrical voltages, wherein the intermediate flange comprises an insulating material, and wherein the photocathode and the second housing are maintained at different electrical voltages.

16. An apparatus comprising:
a scintillation radiation detector comprising:
a photomultiplier comprising:
a first housing; and
a faceplate;

a scintillation crystal;
an optical coupling material interposing and directly contacting the scintillation crystal and the faceplate;
a second housing encompassing the scintillation crystal and the faceplate; and
an intermediate flange connecting the first housing with the second housing, wherein the intermediate flange is located at an axial distance from the faceplate.

17. The apparatus of claim 16 wherein the second housing hermetically seals the scintillation crystal and faceplate.

18. The apparatus of claim 16 wherein the faceplate is connected directly to the second housing.

19. The apparatus of claim 16 wherein the photomultiplier further comprises:
a photocathode located on the faceplate opposite the optical coupling material; and
a focusing electrode, wherein the intermediate flange is located closer to the focusing electrode than the photocathode.

20. The apparatus of claim 16 wherein the intermediate flange comprises:
a first flange portion connected with the first housing;
a second flange portion connected with the second housing; and
a third flange portion directly or indirectly connected with the faceplate to maintain the faceplate against the optical coupling material, wherein the third flange portion is located radially inwards from the second flange portion.

21. The apparatus of claim 16 wherein the scintillation radiation detector further comprises a faceplate flange disposed at least partially within the second housing, and wherein the faceplate flange extends between and connects the faceplate with the intermediate flange to maintain the faceplate against the optical coupling material.

22. The apparatus of claim 16 wherein the first housing comprises glass, and wherein the intermediate flange comprises a metal ring connected with and extending around the first housing.

23. The apparatus of claim 16 wherein the first housing comprises a plurality of insulator rings electrically insulating a plurality of dynodes and/or focusing electrodes of the photomultiplier from each other, and wherein the intermediate flange is connected with at least one of the plurality of the insulator rings to electrically insulate the intermediate flange from an adjacent at least one of the plurality of dynodes and/or focusing electrodes.

24. The apparatus of claim 23 wherein the intermediate flange is connected with an end ring of the plurality of the insulator rings.

25. The apparatus of claim 23 wherein the intermediate flange comprises a side surface connected with a corresponding side surface of one of the plurality of the insulator rings.

26. The apparatus of claim 16 wherein the photomultiplier further comprises:
an anode; and
a photocathode deposited on the faceplate, wherein the anode and photocathode are maintained at different electrical voltages, wherein the intermediate flange comprises metal, and wherein the photocathode and the second housing are maintained at the same electrical voltage.

27. The apparatus of claim 16 wherein the photomultiplier further comprises:
an anode; and
a photocathode deposited on the faceplate, wherein the anode and photocathode are maintained at different electrical voltages, wherein the intermediate flange comprises an insulating material, and wherein the photocathode and the second housing are maintained at different electrical voltages.

28. A scintillation radiation detector comprising:
a photomultiplier comprising a first housing, a faceplate, a photocathode located on the faceplate, and a focus

Assignees

• Stephenson Ken
• Wraight Peter
• Ziegler Wolfgang
• Stoller Christian
• Molodetsky Irina
• Simonetti John J
• Simonetti Donna
• Schlumberger Technology Corp

Inventors

• Stephenson Ken
• Wraight Peter
• Ziegler Wolfgang
• Stoller Christian
• Molodetsky Irina
• Simonetti John J

Classifications

• G01T1/2006 Primary

  using a combination of a scintillator and photodetector which measures the means radiation intensity · CPC title

• G01T1/2023 Primary

  Selection of materials · CPC title

• H01J40/18

  with luminescent coatings for influencing the sensitivity of the tube, e.g. by converting the input wavelength · CPC title

• G01V5/04

  specially adapted for well-logging · CPC title