Light source

• US 7,230,371 B2
• Filed: 03/17/2005
• Issued: 06/12/2007
• Est. Priority Date: 07/27/2004
• Status: Expired due to Fees

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Nanataki, Tsutomu, Akao, Takayoshi, Ohwada, Iwao, Takeuchi, Yukihisa
• Primary Examiner(s): Vo; Tuyet Thi
• Application Number:
  US11/083,052
• Publication Number:
  US 20060022604A1
• Time in Patent Office: 817 Days
• Field of Search: 313/309, 313/310, 313/311, 313/495, 313/496, 313/492, 313/494, 313506-509, 313/498, 313/503, 313/491, 315/169.3, 315/169.4
• US Class Current: 313/309
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• CPC Class Codes: H01J 1/312 having an electric field perpendicular to the surface, e.g. tunnel-effect cathodes of metal-insulator-metal [MIM] type H01J1/304- H01J1/308 take precedence
• CPC Class Codes: H01J 2201/306 Ferroelectric cathodes
• CPC Class Codes: H01J 63/08 Lamps with gas plasma excited by the ray or stream

Abstract

A light source has a rear glass substrate and a front glass substrate having a plate surface disposed in facing relation to a principal surface of the rear glass substrate. The plate surface of the front glass substrate is coated with a phosphor. A two-dimensional array of electron emitters is disposed on the principal surface of the rear glass substrate. A space defined between the rear glass substrate and the front glass substrate is filled with a gas. The gas may be an Hg (mercury) gas or an Xe (xenon) gas.

Claims

1. A light source of a discharge lamp type, wherein

electrons ignite or assist in an electric discharge;

a source of said electrons comprises an electron emitter; and

said electron emitter comprises an emitter of a dielectric material and a first electrode and a second electrode which a drive voltage is applicable to emit electrons from said emitter;

said first electrode being disposed on a first surface of said emitter;

said second electrode being disposed on a second surface of said emitter;

at least said first electrode having a plurality of through regions through which said emitter is exposed; and

each of said through regions has a peripheral portion having a surface facing said emitter and spaced from said emitter.

2. A light source according to claim 1, wherein said first electrode emits electrons toward said emitter to charge said emitter in a first stage;

and

said emitter emits electrons in a second stage.

3. A light source according to claim 1, wherein electrons depending on an amount of charges on said emitter in a first stage are emitted from said emitter in a second stage.

4. A light source according to claim 1, wherein an amount of charges on said emitter in a first stage is maintained until electrons are emitted from said emitter in a second stage.

5. A light source according to claim 1, wherein said emitter is made of a piezoelectric material, an anti-ferroelectric material, or an electrostrictive material.

6. A light source according to claim 1, including:

means for applying AC pulses between said first electrode and said second electrode to cause at least said portion of said emitter to have its polarization inverted or changed;

wherein electrons are intermittently emitted from said emitter.

7. A light source according to claim 6, wherein before light emitted by a first emission of electrons is extinguished, next electrons are emitted to emit light continuously.

8. A light source according to claim 1, including:

a plurality of said electron emitters, said electron emitters being arranged in a two-dimensional array.

9. A light source according to claim 1, including:

means for modulating said drive voltage based on a control signal to control an amount of electrons emitted from said electron emitter for controlling emitted light.

10. A light source for emitting light by exciting a phosphor with an ultraviolet radiation generated from a gas sealed in a space in said light source, wherein

electrons assist in generating said ultraviolet radiation from said gas;

a source of said electrons comprises an electron emitter; and

said electron emitter comprises an emitter of a dielectric material and a first electrode and a second electrode to which a drive voltage is applicable to emit electrons from said emitter;

said first electrode being disposed on a first surface of said emitter;

said second electrode being disposed on a second surface of said emitter;

at least said first electrode having a plurality of through regions through which said emitter is exposed; and

each of said through regions has a peripheral portion having a surface facing said emitter and spaced from said emitter.

11. A light source according to claim 10, wherein said first electrode emits electrons toward said emitter to charge said emitter in a first stage;

and

said emitter emits electrons in a second stage.

12. A light source according to claim 10, wherein electrons depending on an amount of charges on said emitter in a first stage are emitted from said emitter in a second stage.

13. A light source according to claim 10, wherein an amount of charges on said emitter in a first stage is maintained until electrons are emitted from said emitter in a second stage.

14. A light source according to claim 10, wherein said emitter is made of a piezoelectric material, an anti-ferroelectric material, or an electrostrictive material.

15. A light source according to claim 10, including:

a plurality of said electron emitters, said electron emitters being arranged in a two-dimensional array.

16. A light source according to claim 10, including:

means for modulating said drive voltage based on a control signal to control an amount of electrons emitted from said electron emitter for controlling emitted light.

17. A light source according to claim 10, including:

means for applying AC pulses between said first electrode and said second electrode to cause at least said portion of said emitter to have its polarization inverted or changed;

wherein electrons are intermittently emitted from said emitter.

18. A light source according to claim 17, wherein before light emitted by a first emission of electrons is extinguished, next electrons are emitted to emit light continuously.

19. A light source for emitting light from a phosphor by having electrons and/or ions impinge upon the phosphor, said electrons and/or ions being produced when electrons impinge upon molecules of a gas sealed in a space in said light source and ionize said molecules of the gas, wherein

a source of said electrons comprises an electron emitter;

and

said electron emitter comprises an emitter of a dielectric material and a first electrode and a second electrode to which a drive voltage is applicable to emit electrons from said emitter;

said first electrode being disposed on a first surface of said emitter;

said second electrode being disposed on a second surface of said emitter;

at least said first electrode having a plurality of through regions through which said emitter is exposed; and

each of said through regions has a peripheral portion having a surface facing said emitter and spaced from said emitter.

20. A light source according to claim 19, wherein said first electrode emits electrons toward said emitter to charge said emitter in a first stage;

and

said emitter emits electrons in a second stage.

21. A light source according to claim 19, wherein electrons depending on an amount of charges on said emitter in a first stage are emitted from said emitter in a second stage.

22. A light source according to claim 19, wherein an amount of charges on said emitter in a first stage is maintained until electrons are emitted from said emitter in a second stage.

23. A light source according to claim 19, wherein said emitter is made of a piezoelectric material, an anti-ferroelectric material, or an electrostrictive material.

24. A light source according to claim 19, including:

a plurality of said electron emitters, said electron emitters being arranged in a two-dimensional array.

25. A light source according to claim 19, including:

means for modulating said drive voltage based on a control signal to control an amount of electrons emitted from said electron emitter for controlling emitted light.

26. A light source according to claim 19, including:

means for applying AC pulses between said first electrode and said second electrode to cause at least the portion of said emitter to have its polarization inverted or changed;

wherein electrons are intermittently emitted from said emitter.

27. A light source according to claim 26, wherein before light emitted by a first emission of electrons is extinguished, next electrons are emitted to emit light continuously.