Field emission cold-cathode device
AssigneeKabushiki Kaisha Toshiba
InventorMasayuki Nakamoto
Life of this patent
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Abstract
A field emission cold-cathode device includes a support member and a plurality of emitters formed on said support member to emit electrons. Each emitter is made up of a plurality of carbon nanotubes basically constituted by an array of 6-membered rings of carbon. 70% or more of all of the carbon nanotubes have diameters of 30 nm or less. An aspect ratio representing the ratio of the height to the bottom diameter of the carbon nanotube forming the emitter is set at from 3 to 1.times.10.sup.3. The period of the 6-membered rings of carbon in the carbon nanotube is a multiple of 0.426 nm or 0.738 nm.
Claims21
A vacuum micro device comprising:
- a support member;
- an emitter formed on said support member to emit electrons, said emitter comprising a fullerene or a carbon nanotube arranged to cause said emitter to emit electrons with an improved field emission efficiency;
- a surrounding member configured to form, together with said support member, a vacuum discharge space surrounding said emitter;
- and
- an extracting electrode formed to be spaced apart from said emitter, said emitter emitting electrons due to a potential difference between said emitter and said extracting electrode,
- wherein said carbon nanotube is defined by a cylindrical wall formed by winding a graphite sheet, which essentially includes an array of 6-membered rings of carbon, in a direction in which the 6-membered rings has a period substantially of 0.426 nm or 0.738 nm.
An image display device comprising:
- a support member;
- an emitter formed on said support member to emit electrons, said emitter comprising a fullerene or a carbon nanotube arranged to cause said emitter to emit electrons with an improved field emission efficiency;
- a surrounding member configured to form, together with said support member, a vacuum discharge space surrounding said emitter;
- an extracting electrode formed to be spaced apart from said emitter, said emitter emitting electrons due to a potential difference between said emitter and said extracting electrode;
- and
- a display portion configured to display an image in accordance with excitation by electrons emitted from said emitter, said display portion being turned on and off under a control of the potential difference between said emitter and said extracting electrode, on which emission of electrons from said emitter depends,
- wherein said carbon nanotube is defined by a cylindrical wall formed by winding a graphite sheet, which essentially includes an array of 6-membered rings of carbon in a direction in which the 6-membered rings has a period substantially of 0.426 nm or 0.738 nm.
Dependencies are inferred from the claim text.