Claims
- 1. A self collimating electron beam producing arrangement, comprising:
- (a) a first horizontally extending dielectric substrate including a conductive matrix address strip supporting a vertically upwardly extending needle-like field emission cathode electrode;
- (b) a gate anode electrode in the form of a conductive matrix address strip on a second dielectric substrate and including a aperture therethrough, said second substrate being disposed in parallel spaced apart relationship above said first dielectric substrate such that said cathode electrode extends into said aperture;
- (c) a target anode electrode spaced above said second substrate;
- (d) means for supplying operating voltage to each of said electrodes so as to cause a beam of electrons to be emitted from said cathode electrode and move through said aperture towards said target anode electrode; and
- (e) means for contracting the cross-sectional configuration of said electron beam immediately above the aperture in said matrix address strip on said second dielectric substrate forming said gate anode electrode, said path altering means consisting essentially of a third substrate disposed on top of said second substrate and spaced from said target anode electrode throughout its extent, said third substrate including a through-hole positioned in coaxial relationship with the aperture in said matrix address strip on said second substrate such that the rim of the hole through said third substrate is initially bombarded by electrons emitted from said cathode electrode when the latter is initially caused to emit said electron beam, at least the rim of said third substrate consisting essentially of a dielectric material which will charge up negatively as a result of the initial bombardment of said electrons from said cathode electrode to a degree sufficient to deflect all subsequent oncoming electrons from said cathode electrode and thereby cause the cross-sectional configuration of the beam to contract within the dielectric rim.
- 2. A self collimating electron beam producing arrangement, comprising:
- (a) a first horizontally extending dielectric substrate including conductive matrix address strip means supporting a plurality of closely spaced vertically upwardly extending needle-like field emission cathode electrodes;
- (b) a gate anode electrode in the form of conductive matrix address strip means on a second dielectric substrate and including a aperture therethrough for each of said cathode electrodes, said second dielectric substrate being disposed in parallel spaced apart relationship above said first substrate such that each of said cathode electrodes extends into an associated one of said apertures;
- (c) a target anode electrode spaced above said second substrate;
- (d) means for supplying operating voltage to each of said electrodes so as to cause a beam of electrons to be emitted from each of said cathode electrode and move through its associated aperture towards said target anode electrode in a controlled manner; and
- (e) means for contracting the cross-sectional configuration of each of said electron beams immediately above its associated aperture gate, said path altering means consisting essentially of a third substrate disposed on top of said second substrate and spaced from said target anode electrode throughout its extent, said third substrate including a through-hole positioned in coaxial relationship with each of said apertures such that the rim of each of the holes through said third substrate is initially bombarded by electrons emitted from its associated cathode electrode when the latter is initially caused to emit said electron beam, at least each of the rims of said third substrate consisting essentially of a dielectric material which will charge up negatively as a result of the initial bombardment of said electrons from its associated cathode electrode to a degree sufficient to deflect all subsequent oncoming electrons from its associated said cathode electrode and thereby cause the cross-sectional configuration of the associated beam to contact within the dielectric rim.
- 3. An improvement in a display system having matrix of electron emissive structures associated with a matrix of pixels formed upon a screen element, wherein each electron emissive structure includes at least one field emission cathode structure including a field emission cathode electrode, a gate electrode in close proximity to but spaced from said cathode electrode by a dielectric substrate, a target anode electrode spaced a further distance from said cathode electrode than said gate electrode and disposed over the extent of said screen element, means for supplying operating voltage to each of said electrodes so as to cause electrons to be emitted from said cathode electrode and move toward said target anode electrode and impact a pixel associated with said cathode structure to produce light, each electron emissive structure being addressable by a conductive matrix to selectively illuminate each associated pixel, wherein the improvement comprises:
- means for altering the path of at least some of said electrons as they move from said cathode electrode toward said target anode electrode, said path altering means being supported by said gate electrode and said dielectric substrate and spaced from said target anode electrode over its entire extent, and positioned with respect to each of said electrodes such that it is initially bombarded by electrons emitted from said cathode electrode when the latter is initially caused to emit electrons, said path altering means consisting essentially of a dielectric material which will charge up negatively by the initial bombardment of electrons from said cathode electrode to a degree sufficient to deflect most subsequent oncoming electrons from said cathode electrode and thereby alter their paths of movement toward said target anode electrode and said associated pixel.
- 4. An arrangement according to claim 3 wherein said cathode, gate and target anode electrodes and said operating voltage supply means are designed so that electrons emitted from said cathode electrode form a beam of electrons extending from said cathode electrode toward said target anode electrode, and wherein said dielectric path altering means deflects the electrons forming said beams in a way which contracts its crosssectional configuration.
- 5. An arrangement according to claim 4 wherein said cathode electrode includes a single needle-like electrode structure having a vertically upwardly directed point, said gate anode electrode extends circumferentially around said point of said cathode electrode, and said dielectric path altering means is located in close proximity to said gate electrode and spaced from said target anode electrode throughout its extent.
- 6. An arrangement according to claim 5 including a first horizontal dielectric substrate supporting said needle-like cathode electrode, wherein said gate electrode is disposed upon a second horizontal dielectric substrate having an aperture therethrough, said second dielectric substrate being disposed above and parallel with said first dielectric substrate such that the point of said cathode electrode is concentric with and extends into said aperture, and wherein said dielectric path altering means is in the form of a dielectric substrate having an aperture therethrough, said dielectric substrate being disposed on said second substrate such that their apertures are concentric with one another.
- 7. An arrangement according to claim 6 wherein said dielectric substrate forming said path altering means is silicon dioxide.
Parent Case Info
This is a continuation of application Ser. No. 07/472,338 filed Jan. 29, 1990, now abandoned.
US Referenced Citations (10)
Continuations (1)
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Number |
Date |
Country |
Parent |
472338 |
Jan 1990 |
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