Patent US5587720A successfully refreshed from Google Patents.
US5587720A
Expired / Lapsed
US
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Field emitter array and cleaning method of the same
Assignee: Fujitsu Ltd
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Filing: 1994-07-19
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Granted: 1996-12-24
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Expires: 2014-07-19
Abstract
Abstract A field emitter array includes electron-beam source elements, each including a cathode for emitting electrons and a gate provided in the vicinity of the cathode. To emit electrons from the cathode by the field emission effect, a cathode voltage is applied to the cathode and a gate voltage is applied to the gate. An anode is arranged in proximity to the cathode and supplied with a positive anode voltage to capture electrons from the cathode in a first (e.g., normal or display) mode of operation. In a second (e.g., cleaning) mode of operation of the field emitter array, a negative anode voltage is supplied to the anode to urge electrons emitted by a first cathode, back toward a second cathode supplied with a cathode voltage which attracts electrons, to clean the second cathode.
Inventors
- 👤 Shinya Fukuta
- 👤 Keiichi Betsui
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 20:39
CPC Classifications
H; H01; H01J; H01J31/00; H01J31/08; H01J31/10; H01J31/12; H01J9/00; H01J9/02; H01J9/022; H01J9/025; H01J1/00; H01J1/02; H01J1/30; H01J1/304; H01J1/3042
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
224 words
A method for cleaning a field emitter array that includes an electron-beam source array formed by arranging a plurality of electron-beam source elements, each of said electron-beam source elements including a cathode for emitting electrons and a gate provided in the vicinity of said cathode, a predetermined cathode voltage being applied to said cathode and a predetermined gate voltage being applied to said gate, to emit electrons from said cathode by field emission effect in a first mode of operation of the field emitter array, and an anode arranged facing said electron-beam source elements in proximity to said cathode of each of said electron-beam source elements, applied with a predetermined positive voltage for capturing said electrons emitted from at least one cathode of said electron-beam source elements in the first mode of operation of the field emitter array, said method comprising the steps of: (a) forming an electron beam in a second mode of operation such that the electron beam exists between a cathode pair in a pair of said electron-beam source elements in said electron-beam source array by applying a predetermined excitation voltage between said cathode pair; and (b) applying a predetermined negative voltage to said anode in place of said predetermined positive voltage in the second mode of operation of the field emitter array, substantially concurrently with said forming in step (a).
Claim 2
Independent Claim
224 words
A method for cleaning a field emitter array that includes an electron-beam source array formed by arranging a plurality of electron-beam source elements, each of said electron-beam source elements including a cathode for emitting electrons and a gate provided in the vicinity of said cathode, a predetermined cathode voltage being applied to said cathode and a predetermined gate voltage being applied to said gate, to emit electrons from said cathode by field emission effect in a first mode of operation of the field emitter array, and an anode arranged facing said electron-beam source elements in proximity to said cathode of each of said electron-beam source elements, applied with a predetermined positive voltage for capturing said electrons emitted from at least one cathode of said electron-beam source elements in the first mode of operation of the field emitter array, said method comprising the steps of: (a) forming an electron beam in a second mode of operation such that the electron beam exists between a cathode pair in a pair of said electron-beam source elements in said electron-beam source array by applying a predetermined excitation voltage between said cathode pair; and (b) applying a predetermined negative voltage to said anode in place of said predetermined positive voltage in the second mode of operation of the field emitter array, substantially concurrently with said forming in step (a).
Claim 3
Dependent Claim
68 words
A method as claimed in claim 1, wherein said plurality of electron-beam source elements is divided into a plurality of groups each including a plurality of electron-beam source elements, and wherein said excitation voltage is applied between the cathodes in a first electron-beam source element group included in said plurality of groups, and the cathodes in a second electron-beam source element groups included in said plurality of groups.
Claim 4
Dependent Claim
73 words
A method as claimed in claim 1, further comprising the step of: c) sequentially selecting neighboring pairs of electron-beam source elements, starting from one end of the said electron-beam source array and proceeding to the other, said steps (a) and (b) being performed after each sequential section in said step (c), said predetermined excitation voltage of said step (a) being applied between the cathodes of each selected neighboring pair of electron-beam source elements.
Claim 5
Dependent Claim
53 words
A method as claimed in claim 3, wherein said step (c) includes the substeps of c1) selecting a first pair of electron-beam source elements including first and second electron-beam source elements, and c2) selecting a second pair of electron-beam source elements including the second electron-beam source element and a third electron-beam source element.
Claim 6
Dependent Claim
48 words
A method as claimed in claim 4, wherein said substep (c1) is performed before said substep (c2), and wherein the predetermined excitation voltage applied in said step (a) after the substep (c2), is less than the predetermined excitation voltage applied in said step (a) after the substep (c1).
Claim 7
Dependent Claim
34 words
A method as claimed in claim 1, wherein said step (a) is repeated between neighboring pairs of electron-beam source elements in such a manner that said predetermined excitation voltage is gradually decreased in magnitude.
Claim 8
Dependent Claim
27 words
A method as claimed in claim 1, wherein the first mode of operation is a display mode and the second mode of operation is a cleaning mode.
Claim 9
Dependent Claim
30 words
A method as claimed in claim 1, wherein said second mode of operation is a cleaning mode performed before using the field emitter array in the first mode of operation.
Claim 10
Dependent Claim
218 words
A field emitter array comprising: an electron-beam source array for emitting electrons, said electron-beam source array including a plurality of electron-beam source elements, each of said electron-beam source elements including a cathode for emitting electrons and a gate provided in the vicinity of said cathode, a cathode voltage being applied to said cathode and a predetermined gate voltage being applied to said gate, to emit electrons from said cathode by field emission effect in a first mode of operation of the field emitter array; an anode arranged facing said plurality of electron-beam source elements in proximity to the cathode of each of said electron-beam source elements, supplied with a positive anode voltage for capturing said electrons emitted by at least one cathode of said electron-beam source array in the first mode of operation of the field emitter array; and electron repulsion means for urging said electrons emitted from said electron-beam source elements toward said electron-beam source array, by applying a negative anode voltage to said anode in a second mode of operation of said field emitter array, said electron repulsion means including a power source for applying the negative anode voltage to said anode, and switching means operated when cleaning said electron-beam source elements, for applying to said anode, said predetermined negative voltage generated by said power source.
Claim 11
Dependent Claim
218 words
A field emitter array comprising: an electron-beam source array for emitting electrons, said electron-beam source array including a plurality of electron-beam source elements, each of said electron-beam source elements including a cathode for emitting electrons and a gate provided in the vicinity of said cathode, a cathode voltage being applied to said cathode and a predetermined gate voltage being applied to said gate, to emit electrons from said cathode by field emission effect in a first mode of operation of the field emitter array; an anode arranged facing said plurality of electron-beam source elements in proximity to the cathode of each of said electron-beam source elements, supplied with a positive anode voltage for capturing said electrons emitted by at least one cathode of said electron-beam source array in the first mode of operation of the field emitter array; and electron repulsion means for urging said electrons emitted from said electron-beam source elements toward said electron-beam source array, by applying a negative anode voltage to said anode in a second mode of operation of said field emitter array, said electron repulsion means including a power source for applying the negative anode voltage to said anode, and switching means operated when cleaning said electron-beam source elements, for applying to said anode, said predetermined negative voltage generated by said power source.
Claim 12
Independent Claim
267 words
A method for cleaning a field emitter array that includes an electron-beam source array formed by arranging a plurality of electron-beam source elements, each of said electron-beam source elements including a cathode for emitting electrons and a gate provided in the vicinity of said cathode, a predetermined cathode voltage being applied to said cathode and a predetermined gate voltage being applied to said gate, to emit electrons from said cathode by field emission effect in a first mode of operation of the field emitter array, and an anode arranged facing said electron-beam source elements in proximity to said cathode of each of said electron-beam source elements, applied with a predetermined positive voltage for capturing said electrons emitted from at least one cathode of said electron-beam source elements, said anode being divided into a plurality of anode elements, in the first mode of operation of the field emitter array, said method comprising the steps of: (a) selecting at least one pair of said electron-beam source elements, each pair including a first electron-beam source element and a second electron-beam source element; (b) generating at least one electron beam in a second mode of operation such that each electron beam exists between the cathode in said first electron-beam source element and a cathode in said second electron-beam source element, by applying a predetermined excitation voltage therebetween; and (c) applying negative voltages to said anode elements substantially concurrently with said generating in step (b) in such a manner that said negative voltages increase in magnitude along a direction extending from said first electron-beam source element toward said second electron-beam source element.
Claim 13
Independent Claim
267 words
A method for cleaning a field emitter array that includes an electron-beam source array formed by arranging a plurality of electron-beam source elements, each of said electron-beam source elements including a cathode for emitting electrons and a gate provided in the vicinity of said cathode, a predetermined cathode voltage being applied to said cathode and a predetermined gate voltage being applied to said gate, to emit electrons from said cathode by field emission effect in a first mode of operation of the field emitter array, and an anode arranged facing said electron-beam source elements in proximity to said cathode of each of said electron-beam source elements, applied with a predetermined positive voltage for capturing said electrons emitted from at least one cathode of said electron-beam source elements, said anode being divided into a plurality of anode elements, in the first mode of operation of the field emitter array, said method comprising the steps of: (a) selecting at least one pair of said electron-beam source elements, each pair including a first electron-beam source element and a second electron-beam source element; (b) generating at least one electron beam in a second mode of operation such that each electron beam exists between the cathode in said first electron-beam source element and a cathode in said second electron-beam source element, by applying a predetermined excitation voltage therebetween; and (c) applying negative voltages to said anode elements substantially concurrently with said generating in step (b) in such a manner that said negative voltages increase in magnitude along a direction extending from said first electron-beam source element toward said second electron-beam source element.
Claim 14
Dependent Claim
115 words
A method as claimed in claim 10, wherein said step (a) includes a substep of selecting a first electron-beam source element group and a second electron-beam source element group such that said first electron-beam source element group includes a plurality of electron-beam source elements including said first electron-beam source element, and such that said second electron-beam source element group includes a plurality of electron-beam source elements including said second electron-beam source element, such that an electron beam is generated in said step (b) in such a manner to exist between a plurality of cathode groups in said first electron-beam source element group and a plurality of cathode groups in said second electron-beam source element group.
Claim 15
Dependent Claim
27 words
A method as claimed in claim 10, wherein said first mode of operation is a display mode and the second mode of operation is a cleaning mode.
Claim 16
Dependent Claim
30 words
A method as claimed in claim 10, wherein said second mode of operation is a cleaning mode performed before using the field emitter array in the first mode of operation.
Claim 17
Dependent Claim
177 words
A field emitter array comprising: an electron-beam source array for emitting electrons, said electron-beam source array including a plurality of electron-beam source elements, each of said electron-beam source elements including a cathode for emitting electrons and a gate provided in the vicinity of said cathode, a cathode voltage being applied to said cathode and a predetermined gate voltage being applied to said gate, to emit electrons from said cathode by field emission effect in a display mode of operation of the field emitter array; an anode arranged facing said plurality of electron-beam source elements in proximity to the cathode of each of said electron-beam source elements, supplied with a positive anode voltage for capturing said electrons emitted by at least one cathode of said electron-beam source array in the first mode of operation of the field emitter array; and electron repulsion means for urging said electrons emitted from said electron-beam source elements toward said electron-beam source array, by applying a negative anode voltage to said anode in a cleaning mode of operation of said field emitter array.
Claim 18
Dependent Claim
177 words
A field emitter array comprising: an electron-beam source array for emitting electrons, said electron-beam source array including a plurality of electron-beam source elements, each of said electron-beam source elements including a cathode for emitting electrons and a gate provided in the vicinity of said cathode, a cathode voltage being applied to said cathode and a predetermined gate voltage being applied to said gate, to emit electrons from said cathode by field emission effect in a display mode of operation of the field emitter array; an anode arranged facing said plurality of electron-beam source elements in proximity to the cathode of each of said electron-beam source elements, supplied with a positive anode voltage for capturing said electrons emitted by at least one cathode of said electron-beam source array in the first mode of operation of the field emitter array; and electron repulsion means for urging said electrons emitted from said electron-beam source elements toward said electron-beam source array, by applying a negative anode voltage to said anode in a cleaning mode of operation of said field emitter array.
Claim 19
Dependent Claim
190 words
A field emitter array comprising: an electron-beam source array for emitting electrons, said electron-beam source array including a plurality of electron-beam source elements, each of said electron-beam source elements including a cathode for emitting electrons and a gate provided in the vicinity of said cathode, a cathode voltage being applied to said cathode and a predetermined gate voltage being applied to said gate, to emit electrons from said cathode by field emission effect in a first mode of operation of the field emitter array; an anode arranged facing said plurality of electron-beam source elements in proximity to the cathode of each of said electron-beam source elements, supplied with a positive anode voltage for capturing said electrons emitted by at least one cathode of said electron-beam source array in the first mode of operation of the field emitter array; and electron repulsion means for urging said electrons emitted from said electron-beam source elements toward said electron-beam source array, by applying a negative anode voltage to said anode in a cleaning mode of operation of said field emitter array performed before using said field emitter array in the first mode of operation.
Claim 20
Dependent Claim
190 words
A field emitter array comprising: an electron-beam source array for emitting electrons, said electron-beam source array including a plurality of electron-beam source elements, each of said electron-beam source elements including a cathode for emitting electrons and a gate provided in the vicinity of said cathode, a cathode voltage being applied to said cathode and a predetermined gate voltage being applied to said gate, to emit electrons from said cathode by field emission effect in a first mode of operation of the field emitter array; an anode arranged facing said plurality of electron-beam source elements in proximity to the cathode of each of said electron-beam source elements, supplied with a positive anode voltage for capturing said electrons emitted by at least one cathode of said electron-beam source array in the first mode of operation of the field emitter array; and electron repulsion means for urging said electrons emitted from said electron-beam source elements toward said electron-beam source array, by applying a negative anode voltage to said anode in a cleaning mode of operation of said field emitter array performed before using said field emitter array in the first mode of operation.
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