JPS61224258A - Microwave discharging light source device - Google Patents

Abstract

PURPOSE:To improve luminous output after strengthening microwave entering into a non-electrode lamp by setting the non electrode lamp in a cavity resonator and irradiating microwave from the outside of this lamp, while on the other hand, providing an antenna in the inner side of the lamp and radiating microwave through the antenna. CONSTITUTION:Microwave oscillated in and transmitted from the microwave oscillator 15 of a magnetron 12 is branched into an antenna side waveguide 8 side and a resonator side waveguide 10 side by a branching waveguide 17 and transmitted to these waveguides 8, 10 respectively. The microwave transmitted to the antenna side waveguide 8 side reaches the antenna 7, and it is radiated to the inside face of a non-electrode lamp 2 through the antenna 7. The microwave transmitted to the resonator side waveguide 10 side is transmitted into a cavity resonator 1 through an opening 11 and radiated on the outer surface of the non-electrode lamp 2. As the non-electrode lamp 2 is subjected to the input of microwave from the inside and outside faces, full input is increased and luminous intensity is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a microwave discharge light source device that uses microwaves to generate discharge plasma in an electrodeless lamp to emit light.

[Technical background of the invention]

Electrode lamps have the disadvantage of short lamp life due to blackening of the lamp arc tube due to evaporation of the electrode material.Also, especially in the case of high-pressure discharge lamps, the light output of the lamp is stable from the beginning of lamp operation. There are problems such as a long startup time and a long lamp restart time.

As a light source that overcomes these drawbacks, a microwave discharge light source device using an electrodeless lamp that generates discharge plasma using microwaves to emit light has recently been developed.

A conventional microwave discharge light source device is constructed by guiding the microwaves generated by a microwave oscillator to an antenna using a transmission means such as a cable or waveguide, and covering this antenna with an electrodeless lamp. It had been. Rorui also uses microphone white waves generated by a microwave oscillator,
It had a structure in which the lamp was guided to a cavity resonator via a waveguide, and an electrodeless lamp was installed inside the cavity resonator.

A microwave discharge light source device with such a configuration transmits microwaves oscillated by a microwave oscillator to an antenna or cavity resonator via a cable or waveguide, and irradiates the electrodeless lamp with the microwaves. The substance enclosed in the electrodeless lamp, such as metal vapor or gas, is excited to generate a plasma discharge, thereby emitting light.

[Problems with background technology]

However, when attempting to irradiate an electrodeless lamp with microwaves using only the antenna or cavity resonator described above, reflection loss occurs due to the plasma formed near the lamp surface, and even if the microwave intensity is increased, the lamp cannot be irradiated with microwaves. The input microwave input reaches saturation and no more power can be input. For this reason, the light conversion efficiency with respect to the microwave input becomes saturated, and there is a problem that the emission intensity cannot be increased within a certain amount of yield.

[Purpose of the invention]

The present invention was made based on the above circumstances, and its purpose is to provide a microwave discharge light source device that can enhance the microwave input into the electrodeless lamp and improve the light emission output. It is something to do.

[Summary of the invention]

In order to achieve the above object, the present invention installs an electrodeless lamp inside a cavity resonator, irradiates microwaves from the outside of this lamp, and also installs an antenna inside this lamp, and irradiates microwaves through this antenna. The microwave input path from the antenna and the microwave input path from the cavity resonator are used simultaneously to increase the input of microwaves entering the lamp. .

[Embodiments of the invention]

The present invention will be explained below based on an embodiment shown in FIG.

In the figure, I denotes a cavity resonator, which is in the shape of a paraboloid of revolution with one end open. This cavity resonator! An electrodeless lamp 2 is housed inside.

In the electrodeless lamp 2, a bell-shaped inner glass tube 3 and a bell-shaped outer glass tube 4 are hermetically joined to each other, and a discharge space is formed between these glass tubes 3 and 4. This discharge space is filled with a discharge medium that emits light when excited by microwaves, such as mercury and a rare gas such as argon.

The electrodeless lamp °2 is attached to a support plate 6 made of an insulator by a fixture 5, and this support plate 6 is fixed to the top (bottom in the illustration) of the cavity resonator I. .

7 is an antenna, which is formed of a metal conductor. The antenna 7 passes through the center of the support plate 6 and is fixed to the support plate 6. One end of the antenna 7 extends into the cavity I, and this projecting end is crowned by the electrodeless lamp 2.

The other end of the antenna 7 is guided into an antenna 7 side waveguide 8. The antenna side waveguide 8 is connected to the support plate 6
The support plate 6 has an opening 9 through which the lower surface of the support plate 6 is exposed.

IO is a resonator side waveguide. This resonator side waveguide IO
is in communication with an opening rz opened on the side surface of the resonator 1.

12 is a microwave oscillator, that is, a magnetron, and this magnetron 12 is attached to the oscillator side waveguide I4 via a metal gasket 13. The magnetron I20 microwave oscillation section 15 includes an oscillator side waveguide 14
has been introduced. Note that 16 indicates a magnetron power source. A branch waveguide 17 is connected to the oscillator side waveguide 14. One side 17m of the branch waveguide 17 is connected to the antenna side waveguide 8, and the other side 17b is connected to the resonator side waveguide 10.

Note that 18 is a wire mesh installed at the opening of the cavity resonator I to allow light to pass through, but to prevent leakage of the microphone waveguide.

The operation of the embodiment with such a configuration will be explained.

The microwave oscillated from the magnetron 120 microwave oscillator Z5 is branched by the branch waveguide 17 into the antenna side waveguide 8 side and the resonator side waveguide 10 side, and is transmitted to these waveguides 8°10, respectively. be done.

The microwave transmitted to the side of the antenna gutter wave tube g reaches the antenna 7, and is radiated through the antenna 7 to the inner surface of the electrodeless run f2.

Furthermore, the microwave transmitted to the resonator-side waveguide 10 passes through the opening 11 to the cavity resonator! The light is transmitted inside and irradiated onto the outer surface of the electrodeless lamp 2.

Since the electrodeless lamp "2" is irradiated with microwaves simultaneously from the inside and outside, the mercury and rare gas sealed in the discharge space are excited and produce plasma discharge, and this discharge generates ultraviolet rays, causing the lamp to emit light. It is radiated out of f2.

Since microwaves are input to such a lamp 2 from the inner and outer surfaces of the lamp 2, the total input increases, and therefore the emission intensity increases.

In other words, in the conventional case where only the antenna 7 or only the cavity resonator I was used for the same microwave input, the microwave i4' entering the run f2 from inside or outside the lamp 2 is However, according to the above embodiment, the antenna 7 enters the lamp 2 from the inside of the lamp 2 degrees. Since the microwave power input from the outside of the run f2 is dispersed by the cavity resonator 1, saturation propagation due to reflection on the inner or outer surface of the lamp is unlikely to occur. Microwave input is increased.

Furthermore, the microwave energy output from the magnetron 12 is distributed to the antenna side and the resonator side and input to the lamp 2 as described above, so compared to the case where only the antenna or cavity resonator is used, The light conversion efficiency for magnetron output is improved.

In particular, in the case of this embodiment, a single magnetron 712 is used and the microwaves oscillated from this magnetron 12 are branched by the branching waveguide 17, so the configuration is simple and the expensive magnetron is replaced with one. In addition, the light conversion efficiency for microwave input is improved, and the luminous efficiency is improved.

Note that the present invention may be configured as another embodiment shown in FIG. That is, in the other embodiment shown in FIG. 2, microwaves are transmitted to the antenna side waveguide 8 and the resonator side waveguide 10 from separate magnetrons 20 and 30, respectively.

Even in this case, the microwave input to the run 762
Since the energy is increased compared to the antenna alone or the cavity resonator alone, the light emission output is improved.

Further, in each of the above embodiments, microwaves are transmitted to the antenna 7 through the waveguide 8, but the present invention is not limited to this, and the microwaves may be transmitted to the antenna using a cable or the like.

Furthermore, the method of branching the microwave 97- is not limited to half and half, but can be branched in any distribution.

〔Effect of the invention〕

According to the above-described nine aspects of the present invention, an electrodeless lamp is provided with a path for transmitting microwaves through a waveguide, in addition to a path for transmitting microwaves through an antenna,
Since microwaves are supplied to the electrodeless lamp through both of these paths, the input to the lamp can be increased and the light emission output can be increased.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, and FIG. 2 is a block diagram showing another embodiment of the present invention. I... Cavity resonator, 2... Electrodeless lamp, 7...
Antenna, 8...Antenna side waveguide, IO...Resonator side groove wave tube, 12,20.30...Magnetron, 1
7... Branch waveguide.

Claims (2)

[Claims] (1) An electrodeless lamp that emits light when an enclosed substance is excited by microwaves; an antenna made of a metal conductor that is covered by the lamp and irradiates the lamp with microwaves from inside the lamp; A cavity resonator that houses the lamp and irradiates the lamp with microwaves from outside the lamp, and a microwave oscillator and a waveguide that supply microwaves to the antenna and the cavity resonator. Microwave discharge light source device. (2) The above microwave oscillator uses a single oscillator,
The microwave discharge light source device according to claim 1, wherein the microwave oscillated by the oscillator is branched by a waveguide and supplied to the antenna and the cavity resonator, respectively.