LIGHTING SYSTEM

• US 20070041417A1
• Filed: 08/14/2006
• Published: 02/22/2007
• Est. Priority Date: 08/19/2005
• Status: Active Grant

• Current Assignee: Stanley Electric Company Limited
• Original Assignee: Stanley Electric Company Limited
• Inventors: Kanechika, Masayuki, Matsumoto, Takahiro
• Granted Patent: US 7,447,249 B2
• Time in Patent Office: Days
• US Class Current: 372/55
• CPC Class Codes: H01J 65/044 the field being produced by a separate microwave unit
• CPC Class Codes: H01S 3/0975 using inductive or capacitive excitation
• CPC Class Codes: H01S 3/2232 Carbon dioxide (CO2) or monoxide [CO]

Abstract

A lighting system includes a microwave resonator (2) for generating a standing microwave in the internal space, and a gas cell (6) enclosing a medium is disposed in the internal space of the microwave resonator 2. The lighting system excites the medium in the gas cell (6) by the standing microwave to generate light. The gas cell (6) is replaceably mounted on the microwave resonator (2). The generated light is output to the outside of the microwave resonator (2) through a light lead-out hole (26). Thereby, it is possible to provide a lighting system (including a gas laser) capable of emitting light efficiently with a compact and inexpensive device configuration and of achieving a long life. Moreover, it can also be used as a lighting system in the THz-wave region by enclosing the medium for generating light in the far-infrared region in the gas cell (6).

Claims

1. A lighting system for generating light by exciting a medium such as gas or vapor, comprising:

a microwave resonator having an internal space for generating a standing microwave;

microwave supply means for supplying the microwave into the internal space of the microwave resonator; and

a gas cell enclosing the medium and disposed in the internal space of the microwave resonator,

wherein the light is generated by exciting the medium in the gas cell using the standing microwave generated in the internal space of the microwave resonator and wherein the generated light is output to the outside of the microwave resonator through a light lead-out hole provided in the microwave resonator.

2. A lighting system according to claim 1, wherein the gas cell is disposed in a position corresponding to the maximum electric field strength of the standing wave in the internal space of the microwave resonator or in the vicinity thereof.

3. A lighting system according to claim 1, wherein the gas cell is disposed in a position, or in the vicinity thereof, a distance of (λ

g/2)·

(n+(1/2)) (n;

0 or greater integer) from the position corresponding to zero electric field strength of the standing microwave at one end of the internal space of the microwave resonator, where λ

g is a guide wavelength as the wavelength of the standing microwave in the internal space of the microwave resonator.

4. A lighting system according to claim 1, wherein the electromagnetic field mode of the standing microwave in the internal space of the microwave resonator is a mode in which the electric field strength is constant in a single direction on a cross section of the internal space of the microwave resonator and in which the electric field strength varies in a direction perpendicular to the single direction on the cross section, and wherein the gas cell is disposed in the internal space of the microwave resonator in such a way that the central axis of the gas cell exists in a position corresponding to the maximum electric field strength in the direction perpendicular to the single direction with the central axis directed to the single direction.

5. A lighting system according to claim 3, wherein the electromagnetic field mode of the standing microwave in the internal space of the microwave resonator is a mode in which the electric field strength is constant in a single direction on the cross section of the internal space of the microwave resonator and in which the electric field strength varies in the direction perpendicular to the single direction on the cross section, and wherein the gas cell is disposed in the internal space of the microwave resonator in such a way that the central axis of the gas cell exists in a position corresponding to the maximum electric field strength in the direction perpendicular to the single direction with the central axis directed to the single direction.

6. A lighting system according to claim 1, wherein the gas cell is provided in a plural number and the gas cells are disposed in positions corresponding to the maximum electric field strength of the standing wave in the internal space of the microwave resonator or in the vicinity of the positions, with being spaced from each other in the central axis direction of the internal space.

7. A lighting system according to claim 1, wherein the gas cell is provided in a plural number and the gas cells are disposed in a line on a cross section of the internal space of the microwave resonator in positions corresponding to the maximum electric field strength of the standing wave in the internal space or in the vicinity of the positions.

8. A lighting system according to claim 1, wherein the microwave resonator has at least one short plate for adjusting a cavity length, which is the length of the internal space in the traveling direction of the standing microwave.

9. A lighting system according to claim 1, wherein the gas cell is replaceably mounted on the microwave resonator.

10. A lighting system according to claim 1, wherein the microwave supply means includes a microwave oscillator for outputting at least the microwave and an isolator interposed between the microwave oscillator and the microwave resonator, wherein the microwave supply means supplies the microwave resonator with the output from the microwave oscillator via the isolator.

11. A lighting system according to claim 1, wherein a laser resonator for resonating the light generated in the gas cell and oscillating the laser beam is mounted on the microwave resonator and the light lead-out hole is made in the microwave resonator on the optical axis of the laser beam.

12. A lighting system according to claim 1, wherein the light lead-out hole is made in the microwave resonator in a position opposite the gas cell.

13. A lighting system according to claim 12, wherein a reflective coating layer that reflects the light generated in the gas cell is formed on an outer surface of the gas cell except for one end.

14. A lighting system according to claim 12, wherein a condenser lens for condensing the light output through the light lead-out hole to the outside of the microwave resonator is mounted on the microwave resonator in the place of the light lead-out hole.

15. A lighting system according to claim 1, wherein the medium is of the type of generating light in the far-infrared region.