JP2001093688A - High frequency energy feeder and high-frequency electrodeless discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve existing high-frequency energy feeder using side hollow resonators, which is unsuitable for feeding high-frequency energy such as higher than hundreds watts to a load, because of cable conductors of coaxial lines were used as a high-frequency connecting means. SOLUTION: A high-frequency energy connecting means to side hollow resonators is formed by a feeder port 5. Therefore, a larger quantity of high-frequency energy can be fed to a load than existing high-frequency energy feeders using side hollow resonators.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a high-frequency energy supply device and a high-frequency electrodeless discharge device using the same.

[0002]

2. Description of the Related Art A high frequency electrodeless discharge lamp is easier to couple electromagnetic energy to a filler than an electrode arc discharge lamp, and can eliminate mercury from the filler for discharge luminescence. There is an excellent advantage that high luminous efficiency can be expected because there is no loss. Further, since no electrodes are provided inside the discharge space, blackening of the bulb inner wall due to electrode evaporation does not occur. This makes it possible to greatly extend the lamp life. From these characteristics, high-frequency electrodeless discharge lamps are the next generation of high-intensity discharge lamps.
Research has been actively conducted in recent years.

[0003] Generally, in a discharge lamp device, the smaller the light source, the closer to a point light source, and the light distribution design can be more idealized. For example, in consideration of application to a standard liquid crystal video projector or the like, a plasma arc size of about 3 mm or less is required from the viewpoint of optical design for improving the use efficiency of radiation light. On the other hand, in the electrodeless discharge lamp, the size of the plasma arc is determined by the inner diameter of the bulb. However, in the conventional high frequency electrodeless discharge lamp device using a cavity resonator, the size of the plasma can be reduced depending on the wavelength. Due to the limitations, it is not suitable for applications requiring a high-brightness point light source. Therefore, a high-frequency energy supply device capable of concentratingly supplying a high-frequency resonance electromagnetic field to a space smaller than the cavity resonator has been developed in recent years.

A conventional technique will be described below with reference to FIG. 4 based on "high-frequency energy supply means and high-frequency electrodeless discharge lamp device" disclosed in Japanese Patent Application Laid-Open No. 10-189270.

The high-frequency energy supply device disclosed in the publication has a plurality of side cavity resonators each having an electromagnetic inductive function portion made of a ring-shaped conductive material and an electric capacity function portion made of an air gap. A high-frequency energy required for electric discharge or the like is supplied by a resonance high-frequency electromagnetic field at the center of the ring of a side-cavity resonator group in which a plurality of the side-cavities are arranged in an annular shape such that the capacitive function units face each other. It has a configuration. Accordingly, it is an object of the present invention to provide a high-frequency energy supply device capable of concentratingly supplying a high-frequency resonance electromagnetic field to a space smaller than a cavity resonator, and a high-frequency electrodeless discharge lamp device using the same.

In FIG. 4, as an example of the side cavity resonator group, four sheets of the same conductive material are formed from the inner wall surface of the reflector 43 and the high frequency leakage prevention shield 43, which is made of a conductive material and has a rotationally symmetrical shape. The figure shows a vane-type resonator in which a plate-like vane 42 projects toward the center. The space formed by the inner wall surface between the joined portions of the adjacent vanes 42 and the adjacent vanes 42 functions as an electromagnetic inductive function portion, and the space between the adjacent vane protrusions is provided on the reflector / high-frequency leakage prevention shield 43. Functions as an electric capacitive function unit. The core wire of the coaxial line 44 is electrically connected to one of the vanes 42 by soldering or the like to form a high-frequency coupling unit 45. The high-frequency energy propagated through the coaxial line 44 is coupled to the vane-type resonator by the high-frequency coupling means 45 functioning as an oscillation antenna in the resonator. The dimensions of the vane-type resonator are designed in advance to resonate at the frequency of the high-frequency energy to be coupled. Thus, by placing a load such as the electrodeless discharge tube 41 in the high-frequency resonance electric field _Eres generated at the center of the vane-type resonator, high-frequency energy required for the load such as the electrodeless discharge tube 41 is supplied. You. This allows
When the load is an electrodeless discharge tube, the gas in the electrodeless discharge tube 41 causes discharge and emits light. The radiation emitted by the discharge is reflected by a reflecting mirror 43 made of a conductor, and is extracted outside through a metal net 46. The reflecting mirror 43 and the metal net 46 together function as high-frequency leakage prevention means.

According to the high-frequency discharge energy supply device disclosed in Japanese Patent Application Laid-Open No. Hei 10-189270, it is possible to maintain a plasma having a relatively small size of 10 mm or less even in a high-frequency electrodeless discharge.

[0008]

In the "high-frequency energy supply means and high-frequency electrodeless discharge lamp device" disclosed in this publication, the core of the coaxial line 44 is used as high-frequency coupling means. However, many coaxial lines use an organic material as an insulating layer between the core wire and the jacket conductor, and are not suitable for transmitting too much high-frequency energy. Therefore, in order to supply high-frequency energy such as several hundred W or more to a load, high-frequency energy coupling means capable of coupling high-frequency energy directly from the waveguide to the side cavity resonator group without using a coaxial line is required. , Is a new issue.

[0009]

According to the first aspect of the present invention, a plurality of protrusions are provided toward the inside of a hollow, substantially annular shape to provide a high frequency resonance at a central portion. A side cavity group made of a conductive material that generates an electromagnetic field, a waveguide, and a power supply port for coupling high-frequency energy propagated by the waveguide to the side cavity group; High-frequency energy is supplied to a load using the high-frequency resonant electromagnetic field generated at the center of the resonator group.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS.

(Embodiment 1) FIG. 1 shows a high-frequency energy supply apparatus according to the present invention. (A) is a perspective view, and (b) is a cross-sectional view along XX '.

A vane in which four plate-like vanes 2 also made of a conductive material protrude toward the center from the inner wall surface of a reflecting mirror 3 made of a conductive material such as aluminum and having an annular rotationally symmetric shape. 1 shows a type resonator. In the reflector 3, a space formed by the inner wall surface of the joined adjacent vane 2 and the adjacent vane 2 functions as an electromagnetic inductive function part, and a gap between the adjacent vane protrusions functions as an electric capacitive function part. . These are the same as the high-frequency energy supply device using the conventional side cavity resonator group, and the dimensions of the vane-type resonator are also designed in advance to resonate at the frequency of the high-frequency energy to be coupled. Is the same as

The present invention is characterized in that the high frequency coupling means to the side cavity resonator group is formed by the power supply port 5. The power supply port 5 is formed by making a hole in a part of the wall surface between the joining portions of the reflector 3 and the vane 2. The waveguide 4 is joined to the outer wall surface of the vane-type resonator so as to cover the power supply port 5.

The high-frequency energy propagated through the waveguide 4 blocks the surface current path at the feed port 5. As a result, charges accumulate in the power supply port 5 to create a high-frequency coupling electric field E _cap . Thus, the power supply port 5 functions as a high-frequency coupling unit for forming a high-frequency resonant electromagnetic field in the vane-type resonator. This high-frequency coupling electric field E _cap generates a high-frequency resonance electric field E _res in the center of the vane-type resonator. Therefore,
Wherein by placing the load 1, such as an electrodeless discharge tube in a high-frequency resonance field E _{r es,} high frequency energy is supplied required load.

The coupled high-frequency electric field E generated at the power supply port 5
_As shown in FIG. 1, the direction of the _cap is perpendicular to the direction of the rotationally symmetric axis of the reflecting mirror 3 having a substantially annular shape.
It is desirable that the directions of the waveguide 4 and the power supply port 5 be coupled together. With such a configuration, matching the direction of the coupling with the high frequency resonance field E _res occurring in the central portion of the vane type resonator frequency electric field E _cap, it is possible to improve the binding properties.

FIG. 2 is a front view of a high-frequency electrodeless discharge device using the high-frequency energy supply device of FIG. High-frequency energy generated by the magnetron 7 as high-frequency oscillation means oscillates high-frequency energy inside the waveguide 4 by the oscillation antenna 8. High-frequency energy propagates through the waveguide 4 and is coupled to the vane-type resonator by the feed port 5. By placing the electrodeless discharge tube 1 in the high-frequency resonance electric field _Eres generated therefrom, high-frequency energy is supplied, and the gas in the electrodeless discharge tube 1 causes discharge to emit light. Light emitted by the discharge is reflected by the reflecting mirror 3 made of a conductor such as aluminum, and is extracted outside through the metal net 6. The reflecting mirror 3 and the metal net 6 together function as high-frequency leakage prevention means.

In the high-frequency energy supply device and the high-frequency electrodeless discharge device configured as described above, high-frequency energy can be coupled using only the waveguide 4 and the power supply port 5. The waveguide 4 and the power supply port 5 have a feature that can endure high-frequency energy larger than that of the coaxial line. Therefore, by adopting the configuration as in the present invention, it is possible to supply a larger amount of high-frequency energy to a load than in a high-frequency energy supply device using a conventional side cavity resonator group.

(Embodiment 2) In Embodiment 1, an example in which one power supply port is provided has been described. However, it is also useful to provide a plurality of power supply ports. FIG. 3 shows a front view of a high-frequency energy supply device provided with two power supply ports and a high-frequency electrodeless discharge device using the same. In the same vane-type resonator as that of the first embodiment, two power supply ports 5a and 5b are provided between the joining portions of the reflector 3 and the vane 2. Power supply port 5
Waveguides 4a and 4b are connected to a and 5b, respectively, and high-frequency energy oscillated from magnetrons 7a and 7b is propagated. High frequency to feed port 5a and 5b different directions coupling electric field E _cap a and E _{c ap} b occurs respectively. These two high-frequency coupled electric fields are intended to create two high-frequency resonant electric fields at the center of the vane-type resonator, and are superimposed to form a combined high-frequency resonant electric field _Eres .

Therefore, the two magnetrons 7a and 7
b is different, the combined high-frequency resonance electric field E
_{Since res} changes its direction periodically, the high-frequency energy supplied to a load such as the electrodeless discharge tube 1 becomes more uniform. In addition, it goes without saying that the number of oscillating means can be increased to increase the amount of high-frequency energy to be supplied.

In the second embodiment, an example is shown in which high-frequency energy from a plurality of oscillating means is coupled to a plurality of feed ports 5a and 5b, but the embodiment is not limited to this. Not something. The same effect can be obtained in a configuration in which high-frequency energy oscillated from one oscillating means is branched into a plurality of waveguides while being propagated through the waveguides and supplied from a plurality of power supply ports. To achieve this, the length of the waveguide after branching is adjusted so that the phase difference between the plurality of feed ports becomes appropriate, so that the electric field at the center of the side cavity group is the same as the frequency of the applied high-frequency energy. What is necessary is just to rotate at the same frequency.

Further, in the second embodiment, only the configuration in which the number of the plurality of power supply ports is two has been described.
The same effect can be obtained by using more than one power supply port.

In the first and second embodiments, an example is shown in which a vane-type resonator is used as the side-cavity resonator group. However, other side-cavities such as a hole-slot type resonator are used. The same effect can be obtained by using a resonator group.

In the first and second embodiments, the high-frequency energy supply device using the side cavity resonator group of the present invention is applied to a high-frequency electrodeless discharge lamp device having a reflector. Although shown only in the form, the application field of the high frequency energy supply means of the present invention is not limited to this. For example, in an apparatus using high-frequency discharge such as plasma CVD, a plasma torch, or a gas discharge laser, supply of high-frequency energy by a group of side cavity resonators is useful in order to form a stable discharge plasma having a relatively small diameter. The high-frequency energy supply device of the present invention is useful when a larger energy supply than before is required.

Further, a relatively small-diameter load disposed at the center of the high-frequency energy supply device of the present invention is heated,
The supply of high-frequency energy by the group of side cavity resonators for emitting, melting, or evaporating is useful, and the high-frequency energy supply device of the present invention is also useful when a larger supply of energy than before is required. .

In the first and second embodiments described above, only an example in which a magnetron is used as an oscillating means of high-frequency energy has been described. However, a similar effect can be obtained.

[0026]

As described above, according to the present invention, a remarkable effect that larger high-frequency energy can be supplied to a load as compared with a high-frequency energy supply device using a conventional side cavity resonator group. can get.

[Brief description of the drawings]

FIG. 1 is a perspective view and a sectional view showing a high-frequency energy supply device according to a first embodiment of the present invention.

FIG. 2 is a front view showing the high-frequency electrodeless discharge device according to the first embodiment of the present invention.

FIG. 3 is a front view showing a high-frequency electrodeless discharge device according to a second embodiment of the present invention.

FIG. 4 is a perspective view showing a high-frequency energy supply device including a conventional side cavity resonator group.

[Explanation of symbols]

 1,41 electrodeless discharge tube 2,42 bain 5,5a, 5b power supply port

Claims (6)

[Claims] 1. A group of side cavity resonators having a shape in which a plurality of protrusions are provided toward the inside of a hollow substantially annular shape and generating a high-frequency resonance electromagnetic field at a center portion; a waveguide; A power supply port for coupling high-frequency energy propagated by a wave tube to the side cavity resonator group is provided, and high-frequency energy is supplied to a load using the high-frequency resonance electromagnetic field generated at the center of the side cavity resonator group. A high-frequency energy supply device characterized in that: 2. The high-frequency power supply according to claim 1, wherein the power supply port is provided between a part of any two adjacent ones of the protruding portions, and is provided on a part of the wall having the substantially annular shape. Energy supply device. 3. The high-frequency energy supply device according to claim 2, wherein a direction of a high-frequency coupling electric field generated in the power supply port is perpendicular to a direction of a rotational symmetry axis of the side cavity resonator group. 4. The high-frequency energy supply device according to claim 1, wherein the number of the power supply ports is plural. 5. The high-frequency energy supply device according to claim 1, wherein the side cavity resonator group is a vane type resonator. 6. A high-frequency oscillating means, and wherein the high-frequency oscillating means is provided.
The high-frequency energy supply device according to any of the above, and an electrodeless discharge tube, the electrodeless discharge tube is in the vicinity of the space formed by the inside of the protruding portion tip end of the side cavity resonator group of the high-frequency energy supply device A high-frequency electrodeless discharge device, wherein the high-frequency energy oscillated from the high-frequency oscillator is supplied to the electrodeless discharge tube by the high-frequency energy supply device.