JPS596032B2 - High frequency discharge light source device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high frequency discharge light source device for lighting an electrodeless discharge lamp using high frequency energy within a high frequency cavity.

A high-frequency discharge light source device shown in FIG. 1 has been proposed for lighting an electrodeless discharge lamp using high-frequency waves, particularly microwaves.

That is, the light reflecting plate 2 reflects the microwaves and light generated by the microwave oscillator 5 through the coupling holes 7.
A light transmitting member 3 made of a metal net covers the opening surface of the light reflecting plate 2 and reflects the microwave, but allows the light to substantially pass through.
A microwave cavity resonator 4 consisting of
The spherical electrodeless fluorescent lamp 1 disposed within the cavity resonator 4 is turned on within a microwave electromagnetic field.

8 is a phosphor film coated on the inner surface of the spherical electrodeless fluorescent lamp 1, and 6 is an electric cable for supplying power to the microwave oscillator 5.

In the high-frequency discharge light source device configured in this manner, the light emitted from the fluorescent lamp 1 is emitted directly or reflected by the light reflecting plate 2 and then radiated to the outside of the cavity resonator 4 via the light transmitting body 3. Ru.

Therefore, light source devices that utilize microwave discharge have useful features such as a discharge lamp that does not require electrodes and therefore does not deteriorate due to electrode wear and has a long life. The distribution is determined by the shape of the fluorescent lamp 1 and the reflection plate 2 which also serves as the wall of the cavity resonator 4.

Therefore, in order to obtain illumination with a different light distribution, it is necessary to particularly change the shape of the reflecting plate 2, but in this case, it is also necessary to simultaneously satisfy the conditions for the cavity resonator 4.

The process of finding these conditions involves a lot of trial and error, and the disadvantage is that it is not easy to determine the shape of the reflector 2 that satisfies the light distribution conditions and at the same time satisfies the conditions for the cavity resonator 4. There was.

In this invention, all the walls of the cavity resonator except for the joint with the waveguide are made of a metal mesh light-transmissive member, and there is a non-contact member at a position surrounded by the wall of the cavity resonator in a non-contact manner. The object of the present invention is to provide a high-frequency discharge light source device that eliminates the above-mentioned drawbacks by arranging an electrode discharge lamp.

An embodiment of the present invention will be described below with reference to FIGS. 2 and 3.

FIG. 2 is a broken sectional view showing an embodiment of the present invention.

In the figure, 4 is a cylindrical cavity resonator, which includes a dish-shaped metal waveguide mounting plate 10 and a bottomed cylindrical metal mesh attached to the lower surface of the waveguide mounting plate 10. It is composed of a member 3 (hereinafter referred to as a light transmitting body) that allows light to pass through but reflects high frequency waves.

Reference numeral 9 denotes a waveguide/divider which acts as a waveguide for guiding the microwave from the microwave oscillator 5 and divides the microwave power into two equal parts.

When this waveguide/distributor 9 is attached to a waveguide mounting plate 10, the waveguide mounting plate 10 functions as a connecting portion with the waveguide/distributor 9.

Further, reference numeral 1 denotes an annular fluorescent lamp having a circular cross section, and as shown in the figure, it is provided within the cavity resonator 4 so as to be surrounded by a light transmitting body and not in contact with the cavity resonator 4. There is.

11 is a 180 degree phase shifter, and 12 is a support rod for supporting the fluorescent lamp 1.

In the high frequency discharge light source device having the above configuration, the power of the microwave excited by the oscillator 5 is divided into three parts by the distributor 9, and then the power is divided into three parts by the 180 degree phase shifter 12. A phase difference of 180 degrees is provided.

Therefore, the resonator 4 is excited with two waves having the same amplitude and opposite phase by opening the coupling hole 7.

Therefore, by appropriately selecting the height and diameter of the cavity resonator 4, it is possible to excite a mode wave as shown in FIG. 3 within the cavity resonator 4.

Incidentally, the broken lines in FIG. 3 indicate the lines of magnetic force excited by the coupling hole 7, and the solid lines schematically indicate the lines of electric force perpendicular to the lines of magnetic force.

In the high-frequency discharge light source device having the above configuration, the annular fluorescent lamp 1 disposed in the cavity resonator 4 is excited by the microwave electromagnetic field and is visible like a conventional electrodeless lamp. Generates a ray of light.

Part of the light generated in this manner is reflected by the waveguide mounting plate 10, and most of the other light passes directly through the light transmitting body 3 and is emitted to the outside of the cavity resonator 4.

Therefore, if a light reflecting plate (omitted in the drawing) is provided outside the cavity resonator 4, changing the shape of the light reflecting plate will have no effect on the resonant frequency of the cavity resonator 4. The light distribution can be changed without any problem, and various light distributions can be easily obtained.

Furthermore, when the electrodeless lamp 1 is discharged by high frequency, the temperature of the lamp 1 itself increases significantly, but since the majority of the cavity resonator 4 is made of a metal mesh member, the heat dissipation from the lamp 1 is not sufficient. be exposed.

Therefore, it becomes easy to repeatedly light the lamp.

Furthermore, the glass and cavity resonator 4 that constitute the electrodeless lamp 1
Since the degree of temperature rise, coefficient of thermal conduction, coefficient of thermal expansion, etc. during use of the device differs from that of the metal mesh member that constitutes the metal mesh member, if the electrodeless lamp 1 and the cavity resonator 4 are in contact with each other, There is a possibility that the electrodeless lamp 1 will break due to thermal distortion, but if it is in a non-contact state, such a possibility □ will be reduced.

In the above embodiment, in order to efficiently light the current fluorescent lamp and to avoid heating of the metal mesh due to the current flowing through the metal mesh as much as possible, the cavity resonator 4 is equipped with a structure as shown in FIG. In addition to exciting mode waves, the cavity resonator 4
The waveguide mounting plate 10 is used as a light reflecting plate in the same way as in conventional lighting equipment for annular electrode fluorescent lamps, but the discharge lamp is made spherical to achieve more precise light distribution. If you are trying to achieve this, you should use an ordinary single-circuit waveguide instead of a distributed waveguide, and make the cavity resonator 4 empty of light other than that directly irradiated to the junction surface with the waveguide. It is also possible to control using a light reflecting plate provided outside the body resonator 4.

As explained above, according to the present invention, all walls of the cavity resonator except for the joint with the waveguide are constructed of a metal mesh member that allows light to pass through but reflects high frequencies, and an electrodeless discharge lamp. By providing the light inside the cavity resonator without contacting the cavity, the light distribution can be easily changed using a light reflector provided outside the cavity, and heat radiation from the lamp can be sufficiently achieved. It is possible to provide a high frequency discharge light source device whose lamp is not easily broken.

[Brief explanation of drawings]

FIG. 1 is a cutaway side view showing an already proposed high-frequency discharge light source device, FIG. 2 is a cutaway side view of a high-frequency discharge light source device showing an embodiment of the present invention, and FIG. 3 is a cutaway side view of a high-frequency discharge light source device showing an embodiment of the present invention. It is an electromagnetic field distribution diagram in . In the figure, 1 is an electrodeless lamp, 2 is a light reflecting plate, 3 is a light transmitting body (metal mesh member), 4 is a cavity resonator, 7 is a coupling hole,
911''i distributor, 10 is a waveguide mounting plate, and 11 is a phase shifter. In the figures, the same or corresponding parts are designated by the same reference numerals.

Claims (1)

[Scope of Claims] 1. A high-frequency cavity resonator constructed of a metal mesh member in which all walls except for the connection part with a waveguide pass light but reflect high-frequency waves, and the light of this cavity resonator The apparatus is characterized by comprising an electrodeless discharge lamp disposed in a position not in contact with the inner surface of the high-frequency cavity resonator at a position surrounded by a metal mesh member that reflects the passing Saki-Hanana frequency waves. High frequency discharge light source device. 2. The high-frequency discharge light source device according to claim 1, wherein the metal mesh member that allows light from the cavity resonator to pass through but reflects high-frequency waves has a cylindrical shape.