Filters for use in dosimetry

• US 8,178,853 B2
• Filed: 04/09/2010
• Issued: 05/15/2012
• Est. Priority Date: 01/12/2010
• Status: Active Grant

• Current Assignee: Landauer, Inc. (Fortive Corp.)
• Original Assignee: Landauer, Inc. (Fortive Corp.)
• Inventors: Yoder, R. Craig
• Primary Examiner(s): Gaworecki, Mark R
• Application Number:
  US12/757,132
• Publication Number:
  US 20110168920A1
• Time in Patent Office: 767 Days
• Field of Search: 250/370.03, 250/370.07, 250/482.1, 250/484.4, 250/484.5
• US Class Current: 250/482.1
• CPC Class Codes: G01T 1/105 Read-out devices G01T1/115 takes precedence
• CPC Class Codes: G01T 3/00 Measuring neutron radiation G01T5/00 takes precedence

Abstract

Described is an optically stimulated luminescence (OSL) sensor comprising one or more cylindrical cup-shaped filters.

Claims

1. A device comprising:

an optically stimulated luminescence (OSL) sensor comprising;

a first cylindrical cup-shaped filter having;

a first circular base, a first cylindrical wall extending from the first circular base, and a first recess surrounded by the first circular base and the first cylindrical wall; and

an optically stimulated luminescent material (OSLM) mounted in the first recess of the first cylindrical cup-shaped filter; and

a second cylindrical cup-shaped filter in which the first cylindrical cup-shaped filter is mounted;

wherein the first cylindrical cup-shaped filter comprises a first energy compensating material.

2. The device of claim 1, wherein the first cylindrical cup-shaped filter comprises aluminum.

3. The device of claim 1, wherein the first cylindrical cup-shaped filter comprises a plastic having metal particles dispersed therein.

4. The device of claim 1, wherein the first cylindrical cup-shaped filter comprises aluminum and the second cylindrical cup-shaped filter comprises copper.

5. The device of claim 1, wherein the OSL sensor comprises one or more filter material discs located between the OSLM and the circular base of the first cylindrical cup-shaped filter.

6. The device of claim 5, wherein the OSL sensor comprises a converter material disc located between the OSLM and the first cylindrical cup-shaped filter.

7. The device of claim 6, wherein the converter material disc comprises high-density polyethylene and wherein there is a conformal disc comprising polyethylene located between the OSLM and the converter material disc.

8. The device of claim 6, wherein the first cylindrical cup-shaped filter comprises aluminum.

9. The device of claim 8, wherein the second cylindrical cup-shaped filter comprises copper.

10. The device of claim 1, wherein the OSLM for the OSL sensor comprises an Al₂O₃:

C material.

11. The device of claim 10, wherein the Al₂O₃:

C material has a grain size of 30 to 40 μ

m.

12. A device comprising:

an optically stimulated luminescence (OSL) sensor comprising;

a first cylindrical cup-shaped filter having;

a first circular base, a first cylindrical wall extending from the first circular base, and a first recess surrounded by the first circular base and the first cylindrical wall; and

an optically stimulated luminescent material (OSLM) mounted in the first recess of the first cylindrical cup-shaped filter;

wherein the first cylindrical cup-shaped filter comprises a first energy compensating material;

wherein the OSL sensor comprises one or more filter material discs located between the OSLM and the circular base of the first cylindrical cup-shaped filter; and

wherein the OSL sensor comprises a first reference filter material disc located between the OSLM and the first cylindrical cup-shaped filter.

13. The device of claim 12, wherein the first reference filter material disc comprises polytetrafluorethylene.

14. The device of claim 12, wherein the first cylindrical cup-shaped filter comprises aluminum.

15. The device of claim 12, wherein OSL sensor further comprises a second cylindrical cup-shaped filter in which the first cylindrical cup-shaped filter is mounted.

16. The device of claim 15, wherein the first cylindrical cup-shaped filter comprises aluminum and wherein the second cylindrical cup-shaped filter comprises copper.

17. The device of claim 12, wherein the first cylindrical cup-shaped filter comprises a plastic having metal particles dispersed therein.

18. The device of claim 12, wherein the OSLM for the OSL sensor comprises an Al₂O₃:

C material.

19. The device of claim 18, wherein the Al₂O₃:

C material has a grain size of 30 to 40 μ

m.

20. A device comprising:

an optically stimulated luminescence (OSL) sensor comprising;

a first cylindrical cup-shaped filter having;

a first circular base, a first cylindrical wall extending from the first circular base, and a first recess surrounded by the first circular base and the first cylindrical wall; and

an optically stimulated luminescent material (OSLM) mounted in the first recess of the first cylindrical cup-shaped filter;

wherein the first cylindrical cup-shaped filter comprises a first energy compensating material;

wherein the OSL sensor comprises;

one or more filter material discs located between the OSLM and the circular base of the first cylindrical cup-shaped filter; and

a spring-type retaining ring mounted on an exposed side of the OSLM in the first cylindrical cup-shaped filter and compressed by the first cylindrical wall; and

wherein the retaining ring retains the OSLM and the one or more filter material discs in the first cylindrical cup-shaped filter.

21. The device of claim 20, wherein the first cylindrical cup-shaped filter comprises aluminum.

22. The device of claim 20, wherein OSL sensor further comprises a second cylindrical cup-shaped filter in which the first cylindrical cup-shaped filter is mounted.

23. The device of claim 22, wherein the first cylindrical cup-shaped filter comprises aluminum and the second cylindrical cup-shaped filter comprises copper.

24. The device of claim 20, wherein the first cylindrical cup-shaped filter comprises a plastic having metal particles dispersed therein.

25. The device of claim 20, wherein the OSL sensor comprises a converter material disc located between the OSLM and the first cylindrical cup-shaped filter.

26. The device of claim 25, wherein the converter material disc comprises high-density polyethylene and wherein there is a conformal disc comprising polyethylene located between the OSLM and the converter material disc.

27. The device of claim 20, wherein the OSL sensor comprises a first reference filter material disc located between the OSLM and the first cylindrical cup-shaped filter.

28. The device of claim 27, wherein the first reference filter material disc comprises polytetrafluorethylene.

29. The device of claim 20, wherein the OSLM for the OSL sensor comprises an Al₂O₃:

C material.

30. The device of claim 29, wherein the Al₂O₃:

C material has a grain size of 30 to 40 μ

m.

31. A device comprising:

a dosimeter sled including one or more optically stimulated luminescence (OSL) sensors,

wherein the one or more of the OSL sensors each comprise an optically stimulated luminescent material (OSLM) mounted in a first cylindrical cup-shaped filter,

wherein the first cylindrical cup-shaped filter comprises a first energy compensating material;

wherein each of the one or more OSL sensors comprises;

one or more filter material discs located between the OSLM and a circular base of the first cylindrical cup-shaped filter; and

a spring-type retaining ring mounted on an exposed side of the OSLM in the first cylindrical cup-shaped filter and compressed a first cylindrical wall of the first cylindrical cup-shaped filter, and

wherein the retaining ring retains the OSLM and the one or more filter material discs in the first cylindrical cup-shaped filter.

32. The device of claim 31, wherein the first cylindrical cup-shaped filter is comprises aluminum.

33. The device of claim 31, wherein the first cylindrical cup-shaped filter comprises a plastic having metal particles dispersed therein.

34. The device of claim 31, wherein a first OSL sensor of the one or more OSL sensors comprises a second cylindrical cup-shaped filter in which the first cylindrical cup-shaped filter is mounted.

35. The device of claim 34, wherein the first cylindrical cup-shaped filter comprises aluminum and the second cylindrical cup-shaped filter comprises copper.

36. The device of claim 31, wherein a first OSL sensor of the one or more OSL sensors comprises a converter material disc located between the OSLM and the first cylindrical cup-shaped filter.

37. The device of claim 36, wherein the converter material disc comprises high-density polyethylene and wherein there is a conformal disc comprising polyethylene located between the OSLM and the converter material disc.

38. The device of claim 31, wherein a second OSL sensor of the one or more OSL sensors comprises a first reference filter material disc located between the OSLM and the first cylindrical cup-shaped filter.

39. The device of claim 38, wherein the first reference filter material disc comprises polytetrafluorethylene.

40. The device of claim 38, wherein a third OSL sensor of the one or more OSL sensors comprises a second reference filter material disc, wherein the second reference material disc is located between the OSLM and the first filter, and wherein the third OSL sensor is a comparator sensor for the second OSL sensor.

41. The device of claim 40, wherein the second reference filter material disc comprises polytetrafluorethylene.

42. The device of claim 31, wherein the OSLM for each OSL sensor of the one or more OSL sensors comprises an Al₂O₃:

C material.

43. The device of claim 42, wherein the Al₂O₃:

C material has a grain size of 30 to 40 μ

m.

44. The device of claim 31, wherein the one or more sensors comprise a plurality of sensors, wherein two or more of the one or more sensors each comprise a plastic/metal cylindrical cup-shaped filter having metal particles dispersed in a plastic, and wherein each of the plastic/metal cylindrical cup-shaped filters has metal particles having a different grain size.

45. The device of claim 44, wherein each of the plastic/metal cylindrical cup-shaped filters is the first cylindrical cup-shaped filter.