JP2005285349A - Microwave electrodeless discharge lamp device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microwave electrodeless discharge lamp device capable of outputting more uniform light. <P>SOLUTION: The microwave electrodeless discharge lamp device is composed of a wave guide 3 guiding a microwave generated at a microwave oscillator 2 in an intended direction, a microwave resonator 4 connected to the wave guide 3 resonating with the microwave transmitted through the wave guide 3, a bulb 5 in which mercury as light emitting material is sealed, and an electromagnetic field control means 6 dispersing the microwave. The electromagnetic field control means 6 is, for example, made of an almost rectangular-shaped alumina plate with a length almost the same as that of the bulb 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a microwave electrodeless discharge lamp apparatus that illuminates a bulb with a microwave to light the bulb.

  A conventional example of a microwave electrodeless discharge lamp device is disclosed in, for example, Japanese Patent Application Laid-Open No. 63-224193. In this light source device, which includes a microwave power source, a cavity resonator connected to the microwave power source, and a lamp provided in the cavity resonator, a part of the cavity resonator is formed in a net shape A plurality of lamps are provided.

In the cavity resonator formed into a flat plate shape by this configuration, it is possible to stand a plurality of standing wave crests by electromagnetic waves. It is possible to obtain a light source suitable for the operation.
JP-A 63-224193

  However, in the above-described conventional example, when the microwave that has entered the resonator from the vicinity of the microwave feeding port passes through the discharge space of the lamp, the plasma absorbs energy. However, there is a concern that the light output is reduced at the end of the lamp and the uniformity of the light output is not sufficient.

The present invention has been made in view of such problems, and the object of the present invention is as follows.
It is an object of the present invention to provide a microwave electrodeless discharge lamp apparatus capable of making the light output more uniform.

  The invention according to claim 1 is a microwave oscillator for generating a microwave, a microwave resonator having a microwave power supply port into which the microwave is introduced, and a light emitting material sealed therein and installed in the microwave resonator. A microwave electrodeless discharge lamp device including a bulb is characterized in that the bulb is substantially linear, and electromagnetic field control means for dispersing microwaves is provided between the microwave feeding port and the bulb.

  According to a second aspect of the present invention, in the microwave electrodeless discharge lamp device according to the first aspect, the electromagnetic field control means is made of a dielectric or a conductor.

  According to a third aspect of the present invention, in the microwave electrodeless discharge lamp apparatus according to the first aspect, the electromagnetic field control means is installed near the center of the bulb.

  According to a fourth aspect of the present invention, in the microwave electrodeless discharge lamp apparatus according to the first aspect, the electromagnetic field control means has a microwave transmission hole through which the microwave is transmitted.

  According to a fifth aspect of the present invention, in the microwave electrodeless discharge lamp device according to the third aspect, the electromagnetic field control means is a bulb wall formed thinner than the other part.

  The invention according to claim 6 is the microwave electrodeless discharge lamp device according to claim 1, wherein the electromagnetic field control means is a gap formed by a plurality of valves installed around the microwave power feeding port. The microwave electrodeless discharge lamp device according to claim 1.

  According to the present invention, when the bulb shape of the microwave electrodeless discharge lamp apparatus is made substantially linear, the microwave is dispersed on the bulb surface by the electromagnetic field control means, so that the light output from the bulb is made uniform. be able to.

(First embodiment)
This embodiment will be described with reference to FIGS. FIG. 1 is a block diagram of a microwave electrodeless discharge lamp apparatus according to the present embodiment. FIG. 2 is a plan view (a) of a principal part of the microwave electrodeless discharge lamp device and a cross-sectional view (b) taken along line AA of (a). FIG. 3 is an illuminance distribution diagram at the focal length in the microwave electrodeless discharge lamp apparatus shown in FIG. FIG. 4 is a plan view (a) of a main part of a microwave electrodeless discharge lamp device according to another example of the present embodiment, and a cross-sectional view taken along line AA in FIG.

  A microwave electrodeless discharge lamp apparatus according to this embodiment includes a microwave oscillator 2 connected to a power source 1 as shown in FIG. 1 and a waveguide for guiding the microwave oscillated from the microwave oscillator 2 in a desired direction. 3, a microwave resonator 4 that is connected to the waveguide 3 and resonates with the microwave propagating in the waveguide 3, and a valve that is installed in the microwave resonator 4 and in which mercury that is a luminescent material is enclosed 5 and electromagnetic field control means 6 for dispersing the microwaves.

  The microwave resonator 4 is a case having a substantially elliptical cross section obtained by processing a metal plate, for example, and has a substantially rectangular opening 7 in front view as shown in FIG. Yes. The opening 7 is covered with a mesh-like wire net 8 shown in FIG. The metal mesh 8 is formed with a mesh size that transmits ultraviolet rays emitted from the bulb 5 but does not transmit microwaves. The microwave resonator 4 is provided with a microwave feeding port 9 into which a microwave is introduced. Further, a valve 5 is attached to the microwave resonator 4 by a valve holding means 10 so as to be substantially orthogonal to the microwave power supply port 9. The bulb 5 is formed by sealing both ends of a substantially linear quartz glass tube having a diameter of 33 mm and a length of 1000 mm, and several mg of mercury and rare gas are sealed therein. Further, between the bulb 5 and the microwave power supply port 9, an electromagnetic field control means 6 made of a substantially rectangular alumina plate having a thickness of 2 mm and a length substantially equal to the length of the bulb 4 is provided by means such as screwing ( (Not shown) is attached to the microwave resonator 4.

  In the above configuration, when the microwave oscillator 2 shown in FIG. 1 is supplied with power from the power source 1, for example, a microwave of 2.45 GHz is irradiated toward the waveguide 3. The microwave irradiated to the waveguide 3 propagates through the waveguide 3 and is introduced into the microwave resonator 4 connected to the waveguide 3. The microwave introduced into the microwave resonator 4 is reflected by the inner wall of the microwave resonator 4 and resonates to generate a standing wave. The electric field strength is highest at the antinode of the standing wave, and the electric field generates a discharge in the bulb 5, and ultraviolet rays are emitted from the mercury excited by the generation of the discharge. The ultraviolet rays radiated from the bulb 5 are emitted to the outside through the wall of the bulb 5 and the wire mesh 8 shown in FIG. The metal mesh 8 is configured to transmit the ultraviolet rays emitted from the bulb 5, but not to transmit the microwaves, and most of the microwaves are not emitted to the outside.

  What is important here is that the electromagnetic field control means 6 is provided between the microwave power supply port 9 and the bulb 5 so that the bulb 5 can be irradiated with microwaves substantially uniformly. That is, the microwave introduced into the microwave resonator 4 propagates through the alumina plate (dielectric material) that is the electromagnetic field control means 6 and is distributed over substantially the entire area of the alumina plate, and is substantially uniform on the surface of the bulb 5. A simple microwave is irradiated. Thereby, a relatively uniform discharge is generated in the bulb 5 and uniform light irradiation is possible. Next, the illuminance distribution obtained by the above configuration is shown in FIG. The horizontal axis in FIG. 3 indicates the distance from the center of the bulb 5 to the end of the bulb 5, and the vertical axis indicates the relative illuminance. In FIG. 3, the broken line is the illuminance distribution when the alumina plate as the electromagnetic field control means 6 is not provided, and the solid line is the illuminance distribution when the alumina plate is provided. According to FIG. 3, when the alumina plate is provided, the relative illuminance near the center of the bulb 5 is lower than when the alumina plate is not provided. On the other hand, in the range of ± 30 cm to 60 cm from the bulb, it can be seen that a more uniform illuminance distribution can be obtained by increasing the relative illuminance.

  Further, since the alumina plate has a high light reflectivity, light incident on the alumina plate as the electromagnetic field control means 6 from the bulb 5 is reflected by the alumina plate and emitted from the opening 7 of the microwave resonator 4. The loss of light emitted from the bulb 5 toward the waveguide 3 and absorbed can be suppressed.

In the present embodiment, a substantially rectangular alumina plate is used as the electromagnetic field control means 6, but it may have a substantially semicircular cross section as shown in FIG. In this embodiment, mercury is enclosed in the bulb 5, but a halide or the like may be enclosed. Further, in the present embodiment, an alumina plate that is a dielectric is used as the electromagnetic field control means 6, but a metal plate may be used instead of the alumina plate. In the case where a metal plate is used as the electromagnetic field control means 6, among the microwaves that enter the microwave resonator 4 from the waveguide 3, what is irradiated to the metal plate is reflected by the metal plate. As a result, the microwaves that enter the vicinity of the center of the bulb 5 are reduced, and the microwaves that are incident on other portions except the vicinity of the center of the bulb 5 are increased. That is, since a relatively uniform microwave is incident on the surface of the bulb 5, the light output emitted from the bulb 5 is substantially uniform.
(Second Embodiment)
A second embodiment will be described with reference to FIGS. FIG. 5 is a plan view (a) of a main part of the microwave electrodeless discharge lamp device according to the present embodiment, and a cross-sectional view taken along line AA of (a).
6 is an illuminance distribution diagram of the microwave electrodeless discharge lamp apparatus of FIG. FIG. 7 is a plan view (a) of a principal part of a microwave electrodeless discharge lamp device according to another example of the present embodiment, and a cross-sectional view taken along line AA of (a). FIG. 8 is a plan view (a) of a main part of a microwave electrodeless discharge lamp device according to still another example of the present embodiment, and a cross-sectional view taken along line AA in FIG.

  The microwave electrodeless discharge lamp apparatus of this embodiment is different from the first embodiment in that the electromagnetic field control means 6 is provided only in the vicinity of the region facing the microwave power supply port 9.

  The electromagnetic field control means 6 shown in FIG. 5A is obtained by processing an alumina material into a substantially cylindrical shape, and is provided in the vicinity of the center of the valve 5 that is in the vicinity of the region facing the microwave power supply port 9. The valve 5 passes through. The length of the electromagnetic field control means 6 is 50 mm and is slightly wider than the width of the microwave power supply port 9. The length of the valve 5 is 550 mm and the diameter is 33 mm.

  Also in this configuration, the microwave introduced into the microwave resonator 4 propagates through the alumina (dielectric material) as the electromagnetic field control means 6 and is dispersed over substantially the entire area of the alumina, whereby the surface of the valve 5 Are irradiated with relatively uniform microwaves. Thereby, a relatively uniform discharge is generated in the bulb 5, and a substantially uniform light irradiation is possible.

  Next, the illuminance distribution obtained with the configuration of FIG. 5 is shown in FIG. The horizontal axis in FIG. 6 indicates the distance from the center of the bulb 5 to the end of the bulb 5 as in FIG. 3, and the vertical axis indicates the relative illuminance. In FIG. 6, the broken line is the illuminance distribution when the electromagnetic field control means 6 is not provided, and the solid line is the illuminance distribution when the alumina plate is provided. According to FIG. 6, when the electromagnetic field control means 6 is provided, the relative illuminance near the center of the bulb is lower than when the electromagnetic field control means 6 is not provided. On the other hand, in the range of ± 20 cm to 30 cm from the center of the bulb 5, it can be seen that a uniform illuminance distribution can be obtained by increasing the relative illuminance.

  In the present embodiment, the shape of the electromagnetic field control means 6 is a substantially cylindrical shape. However, as shown in FIG. 7, it may have a cylinder divided in half along the central axis. In this case, the illuminance drop near the center of the bal 5 shown in FIG. 6 can be suppressed, and a more uniform illuminance distribution can be obtained. Further, even if a plurality of holes 20 are provided in the side surface of the cylindrical electromagnetic field control means 6 as shown in FIG. 7, the illuminance drop near the center of the bal 5 shown in FIG. Can be obtained.

(Third embodiment)
A third embodiment will be described with reference to FIGS. FIG. 9 is a plan view (a) of a main part of the microwave electrodeless discharge lamp device according to the present embodiment, and a cross-sectional view taken along line AA of (a). FIG. 10 is a diagram showing an example of use of the electrodeless discharge lamp device of the present embodiment. FIG. 11 is a cross-sectional view of another example of the microwave electrodeless discharge lamp apparatus according to this embodiment.

  This embodiment is different from the above-described embodiment in that the valve 5 is installed so as to block the opening 7 of the microwave resonator 4. That is, the valve 5 has a substantially rectangular parallelepiped shape, and is attached to the microwave resonator 4 so that the valve wall of the valve 5 is in contact with the inner surface of the microwave resonator 4. A plate-like electromagnetic field control means 6 is installed between the valve 5 and the microwave power supply port 9.

  With the above configuration, the microwave introduced from the waveguide 3 into the microwave resonator 4 is reflected, refracted and dispersed by the electromagnetic field control means 6, so that the surface of the bulb 5 is uniformly irradiated with the microwave. The light output from the bulb 5 is substantially uniform. Here, due to the presence of the electromagnetic field control means 6, the number of microwaves reflected in the microwave resonator 4 is small, and a discharge is generated and maintained in the bulb 5 by the traveling wave from the microwave feed port 9 toward the bulb 5. Therefore, the wire mesh 8 (shown in FIG. 2) that plays the role of resonating the microwave in the microwave resonator 4 becomes unnecessary. In this case, light kicking by the wire mesh 8 does not occur, so that the light emission efficiency can be improved.

  An example of using this microwave electrodeless discharge lamp device for sterilization of running water is shown in FIG. In FIG. 10, 30 indicates a water channel through which the running water 31 flows. The microwave electrodeless discharge lamp device is installed by immersing most of the microwave resonator 4 in running water 31 in the water channel 30. In FIG. 10, the power supply 1, the microwave oscillator 2, and the microwave resonator 4 are not shown. In this state, when microwaves are introduced into the microwave resonator 4 from the microwave power supply port 9, most of the introduced microwaves are absorbed by the wall of the valve 5 and are generated in the valve 5. Absorbed by plasma. In addition, since the microwave that is not absorbed by either the wall of the bulb 5 or the plasma is absorbed by the flowing water 31, almost no microwave leaks from the water channel 31 to the outside. Actually, when a microwave of 150 W was introduced using the bulb 5 formed in a substantially rectangular parallelepiped shape having a length of 500 mm, a width of 100 mm, and a thickness of 10 mm, the microwave leaking from the water channel 30 was almost zero.

In the present embodiment, the electromagnetic field control means 6 has a plate shape, but may be processed into a substantially C-shaped cross section as shown in FIG.
(Fourth embodiment)
A fourth embodiment will be described with reference to FIG. FIG. 12 is a plan view (a) of a main part of the microwave electrodeless discharge lamp device of the present embodiment (a) and a cross-sectional view taken along line AA of (a).

The microwave electrodeless discharge lamp apparatus of this embodiment is different from the above embodiment in that the electromagnetic field control means 6 is not a separate member from the bulb 5, but is integrated with the bulb 5, and the others are the same. That is, as shown in FIG. 12, the wall of the bulb 5 is formed thicker in the vicinity of the center of the bulb 5 than in other portions except for the neighborhood of the center. As specific dimensions, the bulb 5 has a substantially cylindrical shape having a length of 500 mm and a diameter of 33 mm, a thickness near the center of the bulb 5 is about 5 mm, and a thickness outside the bulb center is 1.5 mm. In this configuration, when the microwave is irradiated near the center of the bulb 5, the microwave is dispersed in the thick portion near the center of the bulb 5 as described above, and the bulb 5 is irradiated with a relatively uniform microwave. Therefore, the light from the bulb 5 is output uniformly.
(Fifth embodiment)
A fifth embodiment will be described with reference to FIGS. FIG. 13 is a plan view (a) of a principal part of the microwave electrodeless discharge lamp device of the present embodiment (a) and a sectional view (b) taken along the line AA in FIG. FIG. 14 is a view showing another example of the valve 5.

  The first embodiment is that a plurality of valves 5 are installed in the microwave resonator 4, and the electromagnetic field control means 6 is a gap 50 between the plurality of valves installed around the microwave power supply port 9. Different from the embodiment. That is, two substantially linear valves 5 are installed around the microwave power supply port 9 of the microwave resonator 4 shown in FIG. 13 so that the end faces the microwave power supply port 9.

  In this configuration, when a microwave is introduced from the microwave oscillator 2 (not shown in FIG. 13) to the microwave resonator 4, the electromagnetic field distribution in the microwave resonator 4 has a portion where the electric field is maximum. There are a plurality of locations with the maximum electric field strength, such as TE 102 that exists in two locations or TE 104 that has four portions where the electric field is maximum, and thereby, near the microwave feed port 9 of the microwave resonator 4. In this case, since the maximum electric field intensity is not generated, the microwaves are relatively uniformly dispersed in the microwave resonator 3 and irradiated to the bulb 5, and the bulb 5 emits relatively uniform light. As a result of using a substantially cylindrical bulb having a length of 220 mm and a diameter of 33 mm as the bulb 5 and introducing microwave 100 W, light emission is uniform over a region of about 400 mm, which is close to the length of the two bulbs 5. Could get.

  Here, since mercury is sealed in the bulb 5, when one of the two bulbs 5 is lit, the other bulb 5 is irradiated with ultraviolet rays. Since this ultraviolet ray excites mercury enclosed in the other bulb 5, both bulbs 5 can be turned on relatively easily. In the present embodiment, two valves 5 are provided. However, the present invention is not limited to this, and a plurality of valves 5 may be provided so as to surround the microwave power supply port 9 of the microwave resonator 4. Further, as shown in FIG. 14, two valves 5 may be housed in another valve 5.

It is a block diagram of the microwave electrodeless discharge lamp device of a 1st embodiment. It is sectional drawing (b) in AA of the principal part top view (a) and (a) of the microwave electrodeless discharge lamp apparatus of the embodiment. It is an illuminance distribution diagram of the microwave electrodeless discharge lamp device of the embodiment. It is sectional drawing (b) in AA of the principal part top view (a) and (a) of the microwave electrodeless discharge lamp apparatus of another example of the embodiment. It is sectional drawing (b) in AA of the principal part top view (a) and (a) of the microwave electrodeless discharge lamp apparatus of 2nd Embodiment. It is an illuminance distribution diagram of the microwave electrodeless discharge lamp device of the embodiment. It is principal part top view (a) of the other example of the microwave electrodeless discharge lamp apparatus of the same embodiment, and sectional drawing (b) in AA of (a). It is principal part top view (a) and sectional drawing (A) in AA of (a) of the microwave electrodeless discharge lamp apparatus of another example of the embodiment. It is sectional drawing (b) in AA of the principal part top view (a) and (a) of the microwave electrodeless discharge lamp apparatus of 3rd Embodiment. It is the cross section and front view of a microwave electrodeless discharge lamp apparatus. It is a figure which shows the usage example of the electrodeless discharge lamp apparatus of the embodiment. It is sectional drawing of the microwave electrodeless discharge lamp apparatus of another example of the embodiment. It is principal part top view (a) of the microwave electrodeless discharge lamp apparatus of 4th Embodiment, and sectional drawing (b) in AA of (a). It is the cross section and front view of a microwave electrodeless discharge lamp apparatus. It is principal part top view (a) and sectional drawing (b) in AA of (a) of the microwave electrodeless discharge lamp apparatus of 5th Embodiment. It is the cross section and front view of a microwave electrodeless discharge lamp apparatus. It is a figure which shows another example of the valve | bulb 5 of the embodiment.

Explanation of symbols

1 Power Supply 2 Microwave Oscillator 3 Waveguide 4 Microwave Resonator 5 Valve 6 Electromagnetic Field Control Means 7 Opening 8 Wire Mesh 9 Microwave Feed Port

Claims (6)

A microwave oscillator comprising: a microwave oscillator that generates a microwave; a microwave resonator having a microwave power supply port into which the microwave is introduced; and a valve in which a luminescent material is enclosed and installed in the microwave resonator. In the electrode discharge lamp device, the microwave electrodeless discharge lamp device is characterized in that the bulb is substantially linear and electromagnetic field control means for dispersing the microwave is provided between the microwave power supply port and the bulb. 2. The microwave electrodeless discharge lamp device according to claim 1, wherein the electromagnetic field control means is made of a dielectric or a conductor. 2. The microwave electrodeless discharge lamp apparatus according to claim 1, wherein the electromagnetic field control means is installed near the center of the bulb. 2. The microwave electrodeless discharge lamp apparatus according to claim 1, wherein the electromagnetic field control means has a microwave transmission hole through which microwaves are transmitted. 4. The microwave electrodeless discharge lamp device according to claim 3, wherein the electromagnetic field control means is a bulb wall formed thinner than other portions. 2. The microwave electrodeless discharge lamp device according to claim 1, wherein the electromagnetic field control means is a gap formed by a plurality of bulbs installed around a microwave power feeding port.

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