Radiation image acquisition method and apparatus

• US 20010030304A1
• Filed: 02/13/2001
• Published: 10/18/2001
• Est. Priority Date: 02/14/2000
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Kohda, Katsuhiro, Tazaki, Seiji
• Granted Patent: US 6,667,488 B2
• Time in Patent Office: Days
• US Class Current: 250/586
• CPC Class Codes: G01T 1/2012 using stimulable phosphors, e.g. stimulable phosphor sheets
• CPC Class Codes: G01T 1/2014 Reading out of stimulable sheets, e.g. latent image

Abstract

In a radiation image acquisition apparatus that obtains a radiation image recorded on a stimulable phosphor layer having a plurality of arranged cells, the quantity of stimulated emissions from the stimulable phosphor within each cell is obtained precisely for each cell as a digital image signal. A radiation image conversion panel comprising a phosphor layer formed of multiple cells filled with stimulable phosphor having recorded on the surface thereof a radiation image is scanned with a stimulating light beam by a scanning unit, and the stimulated emissions caused thereby are photoelectrically detected as an analog image signal by a photoelectrical amplifier. The signal component representing the partition walls is recognized, and the component of the analog image signal obtained between the recognized signal components representing the cell partition walls is digitized and a digital image signal is obtained.

Claims

1. A method of obtaining a radiation image, comprising the steps of scanning a phosphor layer formed of a plurality of cells, arranged in at least the main scanning direction, filled with stimulable phosphor and bearing thereon a radiation image in the main and a sub-scanning directions with a stimulating light beam, photoelectrically detecting as an analog image signal the stimulated emission emitted by the phosphor layer due to said scanning, and digitizing said analog image signal to obtain a digital image signal representing the radiation image, wherein

a signal component representing the partition walls of said cells included in the analog image signal is recognized, and the digital image signal is obtained from the component of the analog signal obtained between said recognized signal components representing the partition walls.

2. A method of obtaining a radiation image according to

claim 1

, further comprising the steps of mixing a phosphor having light conversion characteristics different from the stimulable phosphor is mixed with either the cell partition walls or the stimulable phosphor contained therebetween, and detecting the fluorescent light emitted from the phosphor in the phosphor layer due to said scanning, and recognizing the signal component representing the partition walls included in the signal of the detected fluorescent light.

3. A method of obtaining a radiation image according to

claim 1

, further comprising the steps of detecting the reflected stimulating light reflected by the phosphor layer due to said scanning, and recognizing the signal component representing the partition walls included in the signal obtained by detecting said reflected stimulating light.

4. A radiation image acquisition method according to

claim 1

, wherein

a mirror surface that raises the reflective-index of the cell partition walls, with respect to the stimulating light, is formed on the upper surface thereof.

5. A radiation image acquisition method according to

claim 3

, wherein

the cell partition walls are tinted so that the reflective index thereof to be weakened, with respect to the stimulating light.

6. A radiation image acquisition method according to

claim 1

, wherein

the cell partition walls are tinted so that the reflective index thereof to be weakened, with respect to the stimulating light.

7. A radiation image acquisition method according to

claim 1

or

2

, wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

8. A radiation image acquisition method according to

claim 3

wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

9. A radiation image acquisition method according to

claim 4

wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

10. A radiation image acquisition method according to

claim 5

wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

11. A radiation image acquisition method according to

claim 1

or

2

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

12. A radiation image acquisition method according to

claim 3

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

13. A radiation image acquisition method according to

claim 4

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

14. A radiation image acquisition method according to claim 5, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

15. A radiation image acquisition method according to

claim 6

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

16. A method of detecting the interval between cells comprising scanning

a phosphor layer formed of a plurality of cells, arranged in at least the main scanning direction, filled with stimulable phosphor and bearing thereon a radiation image in the main and a sub-scanning directions with a stimulating light, photoelectrically detecting as an analog image signal the stimulated emission emitted by the phosphor layer due to said scanning, and digitizing said analog image signal to obtain a digital image signal representing the radiation image, wherein

a signal component representing the partition walls included in the analog signal is recognized, and based on said recognized signal component representing the partition walls, the interval between cells is obtained.

17. A method of detecting the interval between cells as defined in

claim 17

further comprising the steps of mixing a phosphor having light conversion characteristics different from the stimulable phosphor with either the cell partition walls or the stimulable phosphor contained therebetween, detecting fluorescent light emitted from the phosphor material in the phosphor layer due to aforementioned scanning, recognizing the signal component representing the partition walls included in the signal of the detected fluorescent light, and based on said recognized signal component representing the partition walls, obtaining the interval between cells.

18. A method of detecting the interval between cells as defined in

claim 17

further comprising the steps of detecting the reflected stimulated light reflected by the phosphor layer due to said scanning, recognizing the signal component representing the partition walls included in the signal obtained by detecting said reflected stimulating light, and based on said recognized signal component representing the partition walls, obtaining the interval between cells.

26. A radiation image acquisition apparatus according to

claim 17

A radiation image acquisition apparatus according to

claim 17

, wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

33. A radiation image acquisition apparatus according to

claim 17

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

42. A cell interval detection apparatus according to

claim 18

, wherein

a phosphor having light conversion characteristics different from the stimulable phosphor is mixed with either the cell partition walls or the stimulable phosphor contained therebetween and the cell interval detection means recognizes the signal component representing the partition walls included in the signal obtained by detecting the fluorescent light emitted from the phosphor material in the phosphor layer due to aforementioned scanning, and obtains the interval between cells, based on said recognized signal component representing the partition walls.

43. A cell interval detection apparatus according to claim 18, wherein

said cell interval detection means recognizes the signal component representing the partition walls included in the signal obtained by detecting the reflected stimulating light reflected by the phosphor layer when said scanning is performed, and based on said recognized signal component representing the partition walls, the interval between cells is obtained.

19. A radiation image acquisition apparatus comprising a phosphor layer formed of a plurality of cells, arranged in at least the main scanning direction, filled with stimulable phosphor and bearing thereon a radiation image, a scanning apparatus that scans the phosphor layer in the main and a sub-scanning directions with a stimulating light beam, a detection means that photoelectrically detects as an analog image signal the stimulated emission from the phosphor layer caused by the scanning, a signal acquisition means that digitizes the analog image signal to obtain a digital image signal representing the radiation image;

wherein

the detection means recognizes the signal component representing the partition walls included in the analog signal, and obtains the digital image signal from the component of the analog signal obtained between the recognized signal components representing the partition walls.

27. A radiation image acquisition apparatus according to

claim 19

, wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

34. A radiation image acquisition apparatus according to

claim 19

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

40. A radiation image acquisition apparatus according to

claim 27

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

20. A radiation image acquisition apparatus according to

claim 20

, wherein

a phosphor having light conversion characteristics different from the stimulable phosphor is mixed with either the cell partition walls or the stimulable phosphor contained therebetween and the signal acquisition means recognizes the signal component representing the partition walls included in the signal obtained by detection of the fluorescent light emitted from the phosphor material in the phosphor layer due to aforementioned scanning.

21. A radiation image acquisition apparatus according to

claim 20

, wherein

said signal acquisition means recognizes the signal component representing the partition walls included in the signal obtained by detecting the reflected stimulating light reflected by the phosphor layer when said scanning is performed.

22. A radiation image acquisition apparatus according to

claim 20

, wherein

a mirror surface that raises the reflective-index of the cell partition walls with respect to the stimulating light is formed on the upper surface thereof.

23. A radiation image acquisition apparatus according to

claim 22

, wherein

a mirror surface that raises the reflective-index of the cell partition walls with respect to the stimulating light is formed on the upper surface thereof.

24. A radiation image acquisition apparatus according to

claim 20

, wherein

the cell partition walls are tinted so that the reflective index thereof to be weakened with respect to the stimulating light.

25. A radiation image acquisition apparatus according to

claim 22

, wherein

the cell partition walls are tinted so that the reflective index thereof to be weakened with respect to the stimulating light.

28. A radiation image acquisition apparatus according to

claim 20

, wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

29. A radiation image acquisition apparatus according to

claim 21

, wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

30. A radiation image acquisition apparatus according to

claim 22

, wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

31. A radiation image acquisition apparatus according to

claim 23

, wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

32. A radiation image acquisition apparatus according to

claim 24

, wherein

the detected signal component representing the partition walls is used as a trigger signal in digitizing the analog image signal to obtain the digital image signal.

35. A radiation image acquisition apparatus according to

claim 20

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

36. A radiation image acquisition apparatus according to

claim 21

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

37. A radiation image acquisition apparatus according to

claim 22

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

38. A radiation image acquisition apparatus according to

claim 23

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

39. A radiation image acquisition apparatus according to

claim 24

, wherein

the digital image signal is corrected by being divided by the signal component representing the cell partition walls.

41. A cell interval detection apparatus comprising:

a scanning means that scans in the main and a sub-scanning directions with a stimulating light beam the phosphor layer formed of a plurality of cells, arranged in at least a main scanning direction, filled with stimulable phosphor and bearing thereon a radiation image;

a detection means that photoelectrically detects as an analog image signal the stimulated emission from the phosphor layer due to the scanning; and

a cell interval detection means that recognizes the signal component representing the partition walls included in the analog signal, and based on the thus recognized signal component of the partition walls, obtains the interval between cells.