Cleaning of cathode-ray tube display
View Patent ↗Inert gas provided at a suitable level inside a hermetically sealed cathode-ray tube display, typically of the flat-panel type, enables the display's electron-emitting device ( 20 ) to be automatically cleaned during display operation subsequent to final display sealing. Upon being struck by electrons emitted by the electron-emitting device, atoms ( 68 ) of the inert gas ionize to produce positively charged ions ( 124 ) which travel backward to the electron-emitting device and dislodge overlying contaminant material ( 130 and 132 ). A getter ( 26 ) collects dislodged contaminant. A reservoir ( 28 ) provides inert gas to replace inert gas lost during the cleaning process.
1. A structure comprising:
an electron-emitting device which comprises a backplate and an array of laterally separated electron-emissive regions situated over the backplate, each electron-emissive region comprising at least one electron-emissive element;
a light-emitting device coupled to the electron-emitting device to form a hermetically sealed enclosure through which electrons emitted by the electron-emissive regions pass to strike the light-emitting device and cause it to emit light that produces an image; and
inert gas located in open space of the sealed enclosure, the inert gas consisting of at least one of (a) helium at a partial pressure of at least 2×10 −5 torr and (b) at least one of neon, krypton, xenon, and radon at a partial pressure of at least 5×10 −7 torr.
2. A structure as in claim 1 wherein the structure is a flat-panel display.
3. A structure as in claim 1 wherein the light-emitting device comprises:
a faceplate; and
an array of laterally separated light-emissive regions situated over the faceplate, each light-emissive region situated opposite a corresponding different one of the electron-emissive regions.
4. A structure as in claim 1 wherein the electron-emissive regions emit electrons according to field emission.
5. A structure as in claim 1 wherein the inert gas comprises at least one of (a) neon at a partial pressure of at least 1×10 −5 torr and (b) krypton at a partial pressure of at least 1×10 −6 torr.
6. A structure as in claim 1 wherein the inert gas comprises at least one of (a) helium at a partial pressure of at least 5×10 −5 torr, (b) neon at a partial pressure of at least 2×10 −5 torr, (c) krypton at a partial pressure of at least 2×10 −6 torr, and (d) at least one of xenon and radon at a partial pressure of at least 1×10 −6 torr.
7. A structure as in claim 1 wherein the inert gas comprises at least one of (a) helium at a partial pressure of at least 1×10 −4 torr, (b) neon at a partial pressure of at least 5×10 −5 torr, (c) krypton at a partial pressure of at least 5×10 −6 torr, and (d) at least one of xenon and radon at a partial pressure of at least 2×10 −6 torr.
8. A structure as in claim 1 further including a getter for collecting non-inert contaminant material present in the sealed enclosure.
9. A structure as in claim 8 wherein the electron-emitting device has an active electron-emitting portion across which electrons are emitted from the electron-emissive regions, the getter being distributed across the active electron-emitting portion.
10. A structure as in claim 1 further including a reservoir for supplying further inert gas to the open space of the sealed enclosure.
11. A structure as in claim 1 wherein the inert gas is at a partial pressure of no more than 1×10 −1 torr.
12. A structure as in claim 1 wherein the inert gas comprises at least one of (a) helium at a partial pressure of no more than 1×10 −1 torr, (b) neon at a partial pressure of no more than 5×10 −2 torr, (c) krypton at a partial pressure of no more than 5×10 −3 torr, and (d) xenon or radon at a partial pressure of no more than 1×10 −3 torr.
13. A structure comprising:
an electron-emitting device which comprises a backplate and an array of laterally separated electron-emissive regions situated over the backplate, each electron-emissive region comprising at least one electron-emissive element;
a light-emitting device coupled to the electron-emitting device to form a hermetically sealed enclosure through which electrons emitted by the electron-emissive regions pass to strike the light-emitting device and cause it to emit light that produces an image;
inert gas located in open space of the sealed enclosure at a partial pressure of at least 5×10 −7 torr; and
a container that encloses inert gas, the container having a wall through which further inert gas passes from the container to the open space of the sealed enclosure.
14. A structure as in claim 13 wherein the structure is a flat-panel display.
15. A structure as in claim 13 wherein the light-emitting device comprises:
a faceplate; and
an array of laterally separated light-emissive regions situated over the faceplate, each light-emissive region situated opposite a corresponding different one of the electron-emissive regions.
16. A structure as in claim 13 wherein the electron-emissive regions emit electrons according to field emission.
17. A structure as in claim 13 wherein the container is situated in the sealed enclosure.
18. A structure as in claim 13 wherein the wall is gas permeable.
19. A structure as in claim 13 wherein at least part of the inert gas in the container is in gaseous form.
20. A structure as in claim 13 wherein at least part of the inert gas in the container is in inert-gas compound form.
21. A structure as in claim 13 wherein at least part of the inert gas in the container is present in inert-gas absorbent-material form.
22. A structure as in claim 13 further including a getter for collecting non-inert contaminant material present in the sealed enclosure.
23. A structure as in claim 22 wherein the electron-emitting device has an active electron-emitting portion across which electrons are emitted from the electron-emissive regions, the getter being distributed across the active electron-emitting portion.
24. A structure as in claim 13 wherein the inert gas comprises at least one of (a) helium at a partial pressure of at least 2×10 −5 torr, (b) at least one of neon and argon at a partial pressure of at least 1×10 −5 torr, (c) krypton at a partial pressure of at least 1×10 −6 torr, and (d) at least one of xenon and radon at a partial pressure of at least 5×10 −7 torr.
25. A structure as in claim 13 wherein the inert gas comprises at least one of (a) helium at a partial pressure of at least 5×10 −5 torr, (b) at least one of neon and argon at a partial pressure of at least 2×10 −5 torr, (c) krypton at a partial pressure of at least 2×10 −6 torr, and (d) at least one of xenon and radon at a partial pressure of at least 1×10 −6 torr.
26. A structure as in claim 13 wherein the inert gas is at a partial pressure of no more than 1×10 −1 torr.
27. A structure as in claim 13 wherein the inert gas comprises at least one of (a) helium at a partial pressure of no more than 1×10 −1 torr, (b) neon at a partial pressure of no more than 5×10 −2 torr, (c) argon at a partial pressure of no more than 1×10 −2 torr, (d) krypton at a partial pressure of no more than 5×10 −3 torr, and (e) xenon or radon at a partial pressure of no more than 1×10 −3 torr.
28. A method of cleaning a structure comprising an electron-emitting device and a light-emitting device coupled to the electron-emitting device to form a hermetically sealed enclosure through which electrons emitted by an array of laterally separated electron-emissive regions of the electron-emitting device pass to strike the light-emitting device and cause it to emit light that produces an image, open space of the sealed enclosure containing inert gas consisting of at least one of (a) helium at a partial pressure of at least 2×10 −5 torr and (b) at least one of neon, krypton, xenon, and radon at a partial pressure of at least 5×10 −7 torr, the method comprising operating the electron-emitting device so that part of the electrons emitted by the electron-emissive regions collide with atoms of the inert gas to produce inert-gas ions which bombard contaminant material situated over the electron-emitting device in the sealed enclosure and cause at least part of the contaminant material to be dislodged from the electron-emitting device.
29. A method as in claim 28 wherein the structure is a flat-panel display.
30. A method as in claim 28 wherein the electron-emissive regions are situated over a backplate of the electron-emitting device, each electron-emissive region comprising at least one electron-emissive element, the contaminant material attacked by the inert-gas ions comprising contaminant material situated over the electron-emissive elements.
31. A method as in claim 28 wherein the inert gas comprises at least one of (a) neon at a partial pressure of at least 1×10 −5 torr and (b) krypton at a partial pressure of at least 1×10 −6 torr.
32. A method as in claim 28 wherein the inert gas comprises at least one of (a) helium at a partial pressure of at least 5×10 −5 torr, (b) neon at a partial pressure of at least 2×10 −5 torr, (c) krypton at a partial pressure of at least 2×10 −6 torr, and (d) at least one of xenon and radon at a partial pressure of at least 1×10 −6 torr.
33. A method as in claim 28 further including collecting non-inert material, including particles of the dislodged contaminant material, present in the sealed enclosure.
34. A method as in claim 28 further including supplying the open space of the sealed enclosure with further inert gas.
35. A method as in claim 34 further including collecting non-inert material, including particles of the dislodged contaminant material, present in the sealed enclosure.
36. A method as in claim 28 wherein the light-emitting device comprises:
a faceplate; and
an array of laterally separated light-emissive regions situated over the faceplate, each light-emissive region situated opposite a corresponding different one of the electron-emissive regions.
37. A method of cleaning a structure comprising an electron-emitting device and a light-emitting device coupled to the electron-emitting device to form a hermetically sealed enclosure through which electrons emitted by an array of laterally separated electron-emissive regions of the electron-emitting device pass to strike the light-emitting device and cause it to emit light that produces an image, open space of the sealed enclosure containing inert gas at a partial pressure of at least 5×10 −7 torr, the method comprising:
operating the electron-emitting device so that part of the electrons emitted by the electron-emissive regions collide with atoms of the inert gas to produce inert-gas ions which bombard contaminant material situated over the electron-emitting device in the sealed enclosure and cause at least part of the contaminant material to be dislodged from the electron-emitting device; and
supplying the open space of the sealed enclosure with further inert gas from a container having a wall through which the further inert gas passes from the container to the open space of the sealed enclosure.
38. A method as in claim 37 wherein the structure is a flat-panel display.
39. A method as in claim 37 wherein the electron-emissive regions are situated over a backplate of the electron-emitting device, each electron-emissive region comprising at least one electron-emissive element, the contaminant material bombarded by the inert-gas ions comprising contaminant material situated over the electron-emissive elements.
40. A method as in claim 37 further including collecting non-inert material, including particles of the dislodged contaminant material, present in the sealed enclosure.
41. A method as in claim 37 wherein the further inert gas supplied to the open space of the sealed enclosure compensates at least partially for inert-gas ions that lodge in the electron-emitting device.
42. A method as in claim 41 further including collecting non-inert material, including particles of the dislodged contaminant material, present in the sealed enclosure.
43. A method as in claim 37 wherein the inert gas comprises at least one of (a) helium at a partial pressure of at least 2×10 −5 torr, (b) at least one of neon and argon at a partial pressure of at least 1×10 −5 torr, (c) krypton at a partial pressure of at least 1×10 −6 torr, and (d) at least one of xenon and radon at a partial pressure of at least 5×10 −7 torr.
44. A method as in claim 37 wherein the inert gas comprises at least one of (a) helium at a partial pressure of at least 5×10 −5 torr, (b) at least one of neon and argon at a partial pressure of at least 2×10 −5 torr, (c) krypton at a partial pressure of at least 2×10 −6 torr, and (d) at least one of xenon and radon at a partial pressure of at least 1×10 −6 torr.
45. A method as in claim 37 wherein the light-emitting device comprises:
a faceplate; and
an array of laterally separated light-emissive regions situated over the faceplate, each light-emissive region situated opposite a corresponding different one of the electron-emissive regions.
46. A structure comprising:
an electron-emitting device;
a light-emitting device coupled to the electron-emitting device to form a hermetically sealed enclosure through which electrons emitted by the electron-emitting device pass to strike the light-emitting device and cause it to emit light that produces an image;
inert gas located in open space of the sealed enclosure at a partial pressure of at least 5×10 −7 torr; and
a container that encloses inert gas, the container having a wall through which inert gas passes from the container to the open space of the sealed enclosure.
47. A structure as in claim 46 wherein the structure is a flat-panel display.
48. A structure as in claim 46 wherein the wall is gas permeable.
49. A structure as in claim 46 wherein at least part of the inert gas in the container is in gaseous form.
50. A structure as in claim 46 wherein at least part of the inert gas in the container is in inert-gas compound form.
51. A structure as in claim 46 wherein at least part of the inert gas in the container is present in inert-gas absorbent-material form.
52. A structure as in claim 46 further including a getter for collecting non-inert contaminant material present in the sealed enclosure.
53. A structure as in claim 52 wherein the electron-emitting device has an active electron-emitting portion across which electrons are emitted from the electron-emitting device, the getter being distributed across the active electron-emitting portion.
54. A structure as in claim 46 wherein the inert gas comprises at least one of (a) helium at a partial pressure of at least 2×10 −5 torr, (b) at least one of neon and argon at a partial pressure of at least 1×10 −5 torr, (c) krypton at a partial pressure of at least 1×10 −6 torr, and (d) at least one of xenon and radon at a partial pressure of at least 5×10 −7 torr.
55. A structure as in claim 46 wherein the inert gas comprises at least one of (a) helium at a partial pressure of at least 5×10 −5 torr, (b) at least one of neon and argon at a partial pressure of at least 2×10 −5 torr, (c) krypton at a partial pressure of at least 2×10 −6 torr, and (d) at least one of xenon and radon at a partial pressure of at least 1×10 −6 torr.
56. A structure as in claim 46 wherein the inert gas is at a partial pressure of no more than 1×10 −1 torr.
57. A structure as in claim 46 wherein the inert gas comprises at least one of (a) helium at a partial pressure of no more than 1×10 −1 torr, (b) neon at a partial pressure of no more than 5×10 −2 torr, (c) argon at a partial pressure of no more than 1×10 −2 torr, (d) krypton at a partial pressure of no more than 5×10 −3 torr, and (e) xenon or radon at a partial pressure of no more than 1×10 −3 torr.
58. A structure comprising:
an electron-emitting device which comprises a backplate and an array of laterally separated electron-emissive regions situated over the backplate, each electron-emissive region comprising at least one electron-emissive element;
a light-emitting device coupled to the electron-emitting device to form a hermetically sealed enclosure through which electrons emitted by the electron-emissive regions pass to strike the light-emitting device and cause it to emit light that produces an image;
inert gas located in open space of the sealed enclosure at a partial pressure of at least 5×10 −7 torr; and
a reservoir for supplying further inert gas to the open space of the sealed enclosure, the reservoir comprising at least one piece of inert-gas compound material.