Hybrid luminescent device for imaging of ionizing and penetrating radiation

• US 5,594,253 A
• Filed: 05/20/1996
• Issued: 01/14/1997
• Est. Priority Date: 12/28/1994
• Status: Expired due to Term

• Current Assignee: Collimated Holes, Inc.
• Original Assignee: Lockheed Martin Space Operations Company (Martin Marietta Corporation)
• Inventors: Ellisman, Mark H., Bueno, Clifford, Betz, Robert A., Fan, Gary G. Y.
• Primary Examiner(s): Fields, Carolyn E.
• Assistant Examiner(s): Glick, Edward J.
• Application Number:
  US08/650,225
• Time in Patent Office: 239 Days
• Field of Search: 250/483.1, 250/486.1, 250/367, 250/368
• US Class Current: 250/486.1
• CPC Class Codes: G01T 1/201 using scintillating fibres

Abstract

A hybrid luminescent device for converting ionizing and penetrating radiation energy such as x-rays, gamma rays, neutrons, ions, electrons, and the like into visible light for imaging applications. The hybrid luminescent device includes a phosphor screen disposed on an entrance face fiber optics scintillator which, in turn, may be removably coupled to a camera or like recording media. The hybrid luminescent device of the present invention is capable of providing enhanced radiation absorption efficiency, higher spatial resolution and enhanced brightness or luminescence output over that which is achievable by the phosphor screen and/or fiber optics scintillator when used separately as an intensifying screen for imaging of ionizing and/or penetrating radiation.

Claims

1. A hybrid luminescent device for converting penetrating or ionizing radiation into light that can be detected by an electronic or film recording medium and which provides high luminescence output, high radiation absorption efficiency and high spatial resolution irrespective of radiation energy levels, the hybrid luminescent device comprising:

a) a fiber optics scintillator including an entrance face and an exit face, said exit face is adapted for coupling to a light detection device for image recordation, said fiber optics scintillator formed from a non-crystalline amorphous substance and characterized as having;

i) a first radiation absorption efficiency;

ii) a first brightness value;

iii) a first spatial resolution value;

b) a phosphor layer disposed on said entrance face of said fiber optics scintillator, said phosphor layer characterized as having;

i) a second radiation absorption efficiency lower than the first radiation absorption efficiency of said fiber optics scintillator;

ii) a second brightness value higher than the first brightness value of said fiber optics scintillator;

iii) a second spatial resolution value lower than the first spatial resolution value of said fiber optics scintillator; and

wherein

c) the hybrid luminescent device exhibits;

i) a third radiation absorption efficiency higher than the first radiation absorption efficiency of said fiber optics scintillator;

ii) a third brightness value higher than a combined total of the first and second brightness values of said fiber optics scintillator and phosphor layer, respectively; and

iii) a third spatial resolution value about that of the first spatial resolution value of said fiber optics scintillator.

2. The invention as defined in claim 1 wherein said phosphor layer comprises a gadolinium oxysulfide rare earth material.

3. The invention as defined in claim 2 wherein said fiber optics scintillator comprises luminescent terbium-activated borate glass material.

4. The invention as defined in claim 3 wherein the radiation to be converted is x-ray radiation and wherein the hybrid luminescent device provides a radiation absorption efficiency in a range from about 90% to about 100% and a spatial resolution of at least 5 lp/mm.

5. The invention as defined in claim 2 wherein said fiber optics scintillator comprises luminescent terbium-activated silicate glass material.

6. The invention as defined in claim 5 wherein the radiation to be converted is x-ray radiation and wherein the hybrid luminescent device provides a radiation absorption efficiency in a range from about 90% to about 100% and a spatial resolution of at least 5 lp/mm.

7. The invention as defined in claim 2 wherein said fiber optics scintillator comprises cerium-activated, lithium enriched luminescent glass material.

8. The invention as defined in claim 7 wherein the radiation to be converted is x-ray radiation and wherein the hybrid luminescent device provides a radiation absorption efficiency in a range from about 90% to about 100% and a spatial resolution of at least 5 lp/mm.

9. The invention as defined in claim 1 wherein said phosphor layer comprises a zinc-cadmium sulfide, silver- and copper-doped ((ZnCd)S:

Ag,Cu) phosphor material.

10. The invention as defined in claim 9 wherein said fiber optics scintillator comprises luminescent terbium-activated borate glass material.

11. The invention as defined in claim 10 wherein the radiation to be converted is x-ray radiation and wherein the hybrid luminescent device provides a radiation absorption efficiency in a range from about 90% to about 100% and a spatial resolution of at least 5 lp/mm.

12. The invention as defined in claim 9 wherein said fiber optics scintillator comprises luminescent terbium-activated silicate glass material.

13. The invention as defined in claim 12 wherein the radiation to be converted is x-ray radiation and wherein the hybrid luminescent device provides a radiation absorption efficiency in a range from about 90% to about 100% and a spatial resolution of at least 5 lp/mm.

14. The invention as defined in claim 9 wherein said fiber optics scintillator comprises cerium-activated, lithium enriched luminescent glass material.

15. The invention as defined in claim 14 wherein the radiation to be converted is x-ray radiation and wherein the hybrid luminescent device provides a radiation absorption efficiency in a range from about 90% to about 100% and a spatial resolution of at least 10 lp/mm.

16. The invention as defined in claim 1 wherein said phosphor layer comprises a zinc-cadmium sulfide, silver-doped ((ZnCd)S:

Ag) phosphor material.

17. The invention as defined in claim 16 wherein said fiber optics scintillator comprises luminescent terbium-activated borate glass material.

18. The invention as defined in claim 17 wherein the radiation to be converted is electron radiation in a range of about 100-400 keV.

19. The invention as defined in claim 16 wherein said fiber optics scintillator comprises luminescent terbium-activated silicate glass material.

20. The invention as defined in claim 19 wherein the radiation to be converted is electron radiation in a range of about 100-400 keV.

21. The invention as defined in claim 16 wherein said fiber optics scintillator comprises cerium-activated, lithium enriched luminescent glass material.

22. The invention as defined in claim 21 wherein the radiation to be converted is electron radiation in a range of about 100-400 keV.

23. A hybrid luminescent device for converting penetrating or ionizing radiation into light that can be detected by an electronic or film recording medium and which provides high luminescence output, high radiation absorption efficiency and high spatial resolution irrespective of radiation energy levels, the hybrid luminescent device comprising:

a) a fiber optics scintillator including an entrance face and an exit face, said exit face is adapted for coupling to a light detection device for image recordation, said fiber optics scintillator formed from a non-crystalline amorphous substance and characterized as having;

i) a first radiation absorption efficiency;

ii) a first brightness value;

iii) a first spatial resolution value;

b) a phosphor layer disposed on said entrance face of said fiber optics scintillator, said phosphor layer characterized as having;

i) a second radiation absorption efficiency lower than the first radiation absorption efficiency of said fiber optics scintillator;

ii) a second brightness value;

iii) a second spatial resolution value lower than the first spatial resolution value of said fiber optics scintillator; and

wherein;

c) the hybrid luminescent device exhibits;

i) a third radiation absorption efficiency higher than the first radiation absorption efficiency of said fiber optics scintillator;

ii) a third brightness value higher than a highest one of the first and second brightness values of said fiber optics scintillator and phosphor layer, respectively; and

iii) a third spatial resolution value about that of the first spatial resolution value of said fiber optics scintillator.

24. The invention as defined in claim 23 wherein said phosphor layer comprises a gadolinium oxysulfide rare earth material.

25. The invention as defined in claim 24 wherein said fiber optics scintillator comprises luminescent terbium-activated borate glass material.

26. The invention as defined in claim 24 wherein said fiber optics scintillator comprises luminescent terbium-activated silicate glass material.

27. The invention as defined in claim 24 wherein said fiber optics scintillator comprises cerium-activated, lithium enriched luminescent glass material.

28. The invention as defined in claim 23 wherein said phosphor layer comprises a zinc-cadmium sulfide, silver- and copper-doped ((ZnCd)S:

Ag,Cu) phosphor material.

29. The invention as defined in claim 28 wherein said fiber optics scintillator comprises luminescent terbium-activated borate glass material.

30. The invention as defined in claim 28 wherein said fiber optics scintillator comprises luminescent terbium-activated silicate glass material.

31. The invention as defined in claim 28 wherein said fiber optics scintillator comprises cerium-activated, lithium enriched luminescent glass material.

32. The invention as defined in claim 23 wherein said phosphor layer comprises a zinc-cadmium sulfide, silver-doped ((ZnCd)S:

Ag) phosphor material.

33. The invention as defined in claim 32 wherein said fiber optics scintillator comprises luminescent terbium-activated borate glass material.

34. The invention as defined in claim 32 wherein said fiber optics scintillator comprises luminescent terbium-activated silicate glass material.

35. The invention as defined in claim 32 wherein said fiber optics scintillator comprises cerium-activated, lithium enriched luminescent glass material.