X-ray generating method and x-ray generating apparatus

Abstract

An energy beam is irradiated onto a target from an energy beam source, thereby generating an X-ray with an irradiating area to be irradiated onto an object. Then, the X-ray is introduced into a spectrometer, thereby generating an X-ray with parallelism through the selection of wavelength and wavelength range.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

For better understanding of the present invention, reference is made to the attached drawings, wherein

FIG. 1 is across sectional view illustrating an X-ray generating apparatus according to the present invention,

FIG. 2 is an enlarged cross sectional view illustrating a part of the X-ray generating apparatus illustrated in FIG. 1,

FIG. 3 is a structural view illustrating another X-ray generating apparatus according to the present invention, and

FIG. 4 is a structural view illustrating a modified X-ray generating apparatus from the one illustrated in FIG. 3.

Claims

1. A method for generating an X-ray, comprising the steps of: irradiating an energy beam onto a target from an energy beam source, thereby generating an X-ray with an irradiating area to be irradiated onto an object; andintroducing said X-ray into a spectrometer, thereby generating an X-ray with parallelism through the selection of wavelength and wavelength range.

2. The generating method as defined in claim 1, wherein said spectrometer includes a crystal plate.

3. The generating method as defined in claim 2, wherein said crystal plate is made of a material selected from the group consisting of silicon, lithium fluoride (LiF), graphite, germanium and quartz.

4. The generating method as defined in claim 2, wherein said crystal plate is two or more crystal plates which are to be combined.

5. The generating method as defined in claim 4, wherein at least one of said crystal plates functions as an X-ray surface reflective type crystal plate.

6. The generating method as defined in claim 4, wherein at least one of said crystal plates functions as an X-ray transmission type (Laue type) crystal plate.

7. The generating method as defined in claim 4, wherein said crystal plate is made of a cubic crystal such as LiF where two identical reflection planes are mutually perpendicular so as to function as perpendicularly arranged two crystal plates.

8. The generating method as defined in claim 2, wherein said crystal plate includes an X-ray multilayered reflective plate.

9. The generating method as defined in claim 1, further comprising the step of, before introducing said X-ray into said spectrometer, transmitting said X-ray through at least one of an absorptive plate and a slit so as to remove components with unnecessary wavelength of said X-ray.

10. The generating method as defined in claim 9, wherein said absorptive plate is an aluminum plate.

11. The generating method as defined in claim 1, wherein a surface portion of said target to which said energy beam is irradiated is partially melted.

12. The generating method as defined in claim 11, wherein a surface portion of said target to which said energy beam is irradiated is completely melted.

13. The generating method as defined in claim 11, further comprising the step of forming a film on a surface of said target so as to decrease the evaporation velocity of said target by said energy beam.

14. The generating method as defined in claim 13, wherein said film is made of a material selected from the group consisting of BN, graphite, diamond, Be and alumina (Al2O3).

15. The generating method as defined in claim 1, wherein said target is a stationary type target.

16. The generating method as defined in claim 1, wherein said target is a rotating anticathode and said energy beam is irradiated onto a portion of said anticathode which is against the centrifugal force originated from the rotation of said anticathode.

17. The generating method as defined in claim 16, wherein said rotating anticathode includes a cylindrical portion provided along a periphery of said rotating anticathode so that said energy beam is irradiated onto an inner wall of said cylindrical portion.

18. The generating method as defined in claim 17, wherein a side wall of said cylindrical portion is inclined inwardly toward a center axis of said rotating anticathode so that the outer splash of said portion of said target to which said energy beam is irradiated is repressed through the melting of said portion.

19. The generating method as defined in claim 17, wherein a side wall of said cylindrical portion is inclined outwardly from a center axis of said rotating anticathode so that said X-ray can be taken easily out of said target.

20. The generating method as defined in claim 16, wherein said portion to which said energy beam is irradiated is formed in a V-shaped ditch or a U-shaped ditch.

21. The generating method as defined in claim 20, wherein said V-shaped ditch or said U-shaped ditch is formed in the same shape as said centrifugal force affects said portion under melting to which said energy beam is irradiated.

22. The generating method as defined in claim 1, further comprising the step of, in said target, making an area around said portion to which said energy beam is irradiated from a substance with higher melting point and/or higher thermal conductivity than a target material contributing the generation of said X-ray of said target.

23. The generating method as defined in claim 22, wherein said target is a double structured target composed of said target material and said substance with higher melting point and/or higher thermal conductivity than said target material and which is provided at a backside of said target material so that a cooling medium is flowed along said backside of said substance.

24. The generating method as defined in claim 1, wherein said energy beam source is an electron beam source so that said energy beam can be an electron beam.

25. The generating method as defined in claim 24, wherein said electron beam source is a diode or a triode type electron beam source.

26. The generating method as defined in claim 1, wherein said X-ray with parallelism is usable for medical use.

27. An apparatus for generating an X-ray, comprising: a target for generating an X-ray through the irradiation of an energy beam;an energy beam source for generating said energy beam to generate said X-ray so as to have an irradiating area to be irradiated onto an object; anda spectrometer for selecting wavelength and wavelength range of said X-ray through the introduction of said X-ray so as to generate an X-ray with parallelism from said X-ray.

28. The generating apparatus as defined in claim 27, wherein said spectrometer includes a crystal plate.

29. The generating apparatus as defined in claim 28, wherein said crystal plate is made of a material selected from the group consisting of silicon, lithium fluoride (LiF), graphite, germanium and quartz.

30. The generating apparatus as defined in claim 28, wherein said crystal plate is two or more crystal plates which are to be combined.

31. The generating apparatus as defined in claim 30, wherein at least one of said crystal plates functions as an X-ray surface reflective type crystal plate.

32. The generating apparatus as defined in claim 30, wherein at least one of said crystal plates functions as an X-ray transmission type (Laue type) crystal plate.

33. The generating apparatus as defined in claim 30, wherein said crystal plate is made of a cubic crystal such as LiF where two identical reflection planes are mutually perpendicular so as to function as perpendicularly arranged two crystal plates.

34. The generating apparatus as defined in claim 28, wherein said crystal plate includes an X-ray multilayered reflective plate.

35. The generating apparatus as defined in claim 27, further comprising at least one of an absorptive plate and a slit so as to remove components with unnecessary wavelength of said X-ray by transmitting said X-ray through said at least one before said X-ray is introduced into said spectrometer.

36. The generating apparatus as defined in claim 35, wherein said absorptive plate is an aluminum plate.

37. The generating apparatus as defined in claim 27, wherein a surface portion of said target to which said energy beam is irradiated is partially melted.

38. The generating apparatus as defined in claim 37, wherein a surface portion of said target to which said energy beam is irradiated is completely melted.

39. The generating apparatus as defined in claim 37, further comprising a film formed on a surface of said target so as to decrease the evaporation velocity of said target by said energy beam.

40. The generating apparatus as defined in claim 39, wherein said film is made of a material selected from the group consisting of BN, graphite, diamond, Be and alumina (Al2O3).

41. The generating apparatus as defined in claim 27, wherein said target is a stationary type target.

42. The generating apparatus as defined in claim 27, wherein said target is a rotating anticathode and said energy beam is irradiated onto a portion of said anticathode which is against the centrifugal force originated from the rotation of said anticathode.

43. The generating apparatus as defined in claim 42, wherein said rotating anticathode includes a cylindrical portion provided along a periphery of said rotating anticathode so that said energy beam is irradiated onto an inner wall of said cylindrical portion.

44. The generating apparatus as defined in claim 43, wherein a side wall of said cylindrical portion is inclined inwardly toward a center axis of said rotating anticathode so that the outer splash of said portion of said target to which said energy beam is irradiated is repressed through the melting of said portion.

45. The generating apparatus as defined in claim 43, wherein a side wall of said cylindrical portion is inclined outwardly from a center axis of said rotating anticathode so that said X-ray can be taken easily out of said target.

46. The generating apparatus as defined in claim 42, wherein said portion to which said energy beam is irradiated is formed in a V-shaped ditch or a U-shaped ditch.

47. The generating apparatus as defined in claim 46, wherein said V-shaped ditch or said U-shaped ditch is formed in the same shape as said centrifugal force affects said portion under melting to which said energy beam is irradiated.

48. The generating apparatus as defined in claim 27, wherein in said target, an area around said portion to which said energy beam is irradiated is made from a substance with higher melting point and/or higher thermal conductivity than a target material contributing the generation of said X-ray of said target.

49. The generating apparatus as defined in claim 48, wherein said target is a double structured target composed of said target material and said substance with higher melting point and/or higher thermal conductivity than said target material and which is provided at a backside of said target material so that a cooling medium is flowed along said backside of said substance.

50. The generating apparatus as defined in claim 27, wherein said energy beam source is an electron beam source so that said energy beam can be an electron beam.

51. The generating apparatus as defined in claim 50, wherein said electron beam source is a diode or a triode type electron beam source.

52. The generating apparatus as defined in claim 27, wherein said X-ray with parallelism is usable for medical use.