JPS60235325A - Light source unit for microwave discharge - Google Patents

Abstract

PURPOSE:To facilitate manufacturing of a microwave resonance cavity and to improve its mechanical strength as well as to prevent its deformation or breakdown due to mishandling during assembly and the like of the unit, by constituting the microwave resonance cavity with a cylindrical part made of flat meshed materials with its both ends opened, connected to a plane part also made of flat meshed materials. CONSTITUTION:A microwave generated by a magnetron 1 is fed to a microwave resonance cavity 5 enclosed by a cavity wall 6 and a cylindrical meshed materials 7, via a feeding aperture 8 after passing through a wave guide 3 from a magnetron antenna 2. Rare gases within a lamp 9 are electrically discharged by this microwave and the lamp wall will be heated by this energy and then metals such as mercury enclosed in the lamp will be evaporated. Hence, the metal gas discharge of mercury for instance will play a dominant role of discharge and will emit a light with the spectra corresponding to metal compositions. A light transparing member 7 is composed of a first element 7a and a second element 7b, both are made of flat meshed materials and are formed and connected after being cut out of single sheet of meshed materials. This procedure facilitates the control of aperture area and the manufacture of the cavity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to the structure of a microwave discharge light source device that has an electrodeless discharge lamp disposed therein and discharges and emits light using microwave energy.

[Prior art]

Conventionally, there has been a device of this type as shown in FIG.

That is, 1st @ is a cross-sectional view showing a conventional microwave discharge light source device disclosed in Japanese Utility Model Application Publication No. 57-168167. In FIG. 1, 1 is a magnetron that is a microwave oscillator, and 2 is a A magnetron antenna 3 is a waveguide; 5 is a microwave resonant cavity composed of a cavity wall 6 connected to the end of the waveguide 3 and a light-transmitting member 7 such as a spherical metal mesh; 8 is a microwave resonant cavity; A power supply port 9 is provided in the cavity wall 6 to feed microwaves from the waveguide 3 to the microwave resonance cavity 5, and a spherical electrodeless lamp is disposed within the microwave resonance cavity 5. are shown respectively.

In such a conventional microwave discharge light source device, microwaves oscillated by a magnetron 1 are passed from a magnetron antenna 2 through a waveguide 3 and radiated into a microwave resonance cavity 5 from a power feeding port 8.

Due to this microwave, the dregs in the lamp 9 are discharge-excited and emit light, which is originally radiated outward through the entire metal mesh. The emitted light is reflected by a light reflecting surface (not shown), etc., and is irradiated onto the irradiated surface.

In this Yona microwave frequency power source device, most of the energy from the lamp 9 is directly radiated to the outside through the metal mesh, so the light can be efficiently reflected by the light reflecting surface outside the microwave resonant cavity 5. Since the light reflecting mirror is provided outside the microwave resonant cavity 5, this light reflecting surface can be designed without affecting the microwave characteristics of the microwave resonant cavity 5.

However, although conventional microwave discharge light source devices have advantages such as slanting, the shape of the microwave resonant cavity is spherical, so it is difficult to control the aperture ratio during molding, and the mechanical strength is The microwave resonant cavity was difficult to fabricate, making it impractical.

[Summary of the invention]

The object of the present invention is to eliminate all the drawbacks of the conventional ones such as slanting. The second element is joined to the open end of the first element to form a microwave resonant cavity, and the other open end of the first element is joined to the other open end of the first element. By configuring the microwave energy to be supplied from the section, the manufacturing of the microwave resonant cavity is facilitated, the mechanical strength is increased, and the handling during assembly or maintenance of the device is facilitated.
It is an object of the present invention to provide an improved microwave discharge light source device that is not damaged due to CC deformation.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

3, 4, 5 and 6 respectively show cylindrical microwave resonant cavities in microwave discharge light source devices according to four embodiments of the present invention, and FIG. A microwave discharge light source device constructed using the cylindrical microwave resonant cavity shown in FIG. 5 is shown.

In FIG. 2, 4 is a vent, 5 is a cylindrical microwave resonant cavity, and has a light-transmitting member 7 on at least a part of the wall. By forming the light-transmitting member 7 into an electrically continuous mesh member, the sum of the solid angles extending from one point on the lamp 9 to the light-transmitting member 7 side is 2π steradians or more. Reference numeral 8 denotes a power feeding port, which is opened in a portion of the cavity wall 6 made of metal and connected to the waveguide 3, and is used to feed microwaves from the waveguide v3 into the microwave resonant cavity 5.

Reference numeral 9 denotes a lamp, which is filled with rare gas, mercury, etc., and is made of a transparent material such as quartz glass. 10 is a light reflecting surface that reflects the source radiated from the microwave resonance cavity 5;
11 is a cooling fan that cools the magnetron 1 and lamp 9, and 12 is a box that covers the entire body.

In the microwave resonant cavity of the embodiment shown in FIG. 3, a first element 7a is formed by forming a flat mesh member into a cylindrical member with openings at both ends, and 7b is a cylindrical first element 7a.
The second element is a flat mesh-like closing part that is joined to one open end of the element and blocks microwaves inside the first element, the joint part of the 13-piece cylindrical first element 7a, and the 14-piece broken surface is shown. The first
The joints between the element 7a and the second element 7b are shown. Here, the joint portions 13 and 14 are joined by welding, brazing, etc. for electrical continuity.

In the microwave resonant cavity of the embodiment shown in FIG.
This is an annular member arranged along the inside circumference of one open end of b.

In addition, in the microwave resonant cavity of the embodiment shown in FIG. 5, in order to join the first element 7a and the second element 7b, a groove is provided along the outer circumference of one open end of the first element 7a. A metal annular member 15' is provided.

Furthermore, the microwave resonant cavity of the embodiment shown in FIG.
The joint between the element 7a and the reinforcement 7 lanso 16 is shown.

FIG. 7 shows a rectangular prism-shaped microwave resonant cavity according to still another embodiment of the present invention, and the microwave resonant cavity has a first element 7C in which a flat mesh member is formed into a rectangular prism shape with openings at both ends. Micro@ at one open end of the first element 7c.
, and a second element 7d of a flat mesh-like closing portion joined to close the second element 7d.

Next, the operation of the microwave number power source device equipped with each microwave resonant cavity as shown above is as follows. Microwaves oscillated by the Macnetron 1 are fed from a magnetron antenna 2 through a waveguide 3 to a microwave resonant cavity 5 surrounded by a cavity wall 6 and a cylindrical mesh member 7 from a feed port 8 . The rare gas in run f9 is discharged by this microwave, and the lamp wall is heated by this energy, and the enclosed mercury etc. evaporate into a scum, and the discharge is mainly of metal gas such as mercury, and the degree of gas It emits light in a corresponding spectrum. The cylindrical mesh member 7 acts to reflect microwaves, and the emitted light from the lamp 9 is transmitted through the mesh openings. In other words, it acts as an opaque body for microwaves and as a transparent body for light. Therefore, the source from the lamp 9 is completely radiated out from the microwave resonant cavity 5 and is reflected by the light reflecting surface 10.

In the practical use of microwave discharge light sources, it is desired that the microwave resonant cavity minimize microwave leakage and increase the amount of light transmitted, but since both have contradictory characteristics, an optimal value exists. According to experiments, mesh first element 7
a and mesh second element 7b are both made of stainless steel with a thickness of 0.
A thin plate of 1cm is photo-etched into a lattice shape, with a grid pitch of 1mm, a line width of IIolO, and a transmittance of 9.
0% was optimal. Both the first element 7a and the second element 7b of the light-transmitting member 7 are made of flat mesh members, and both are formed by cutting and forming a mesh member from a single mesh member and joining them. It is easy to control the shear opening rate and can be manufactured easily. Further, in the microwave resonant cavity shown in FIG. 3, the joint 13 of the first element 7a and the first element 7a
The joint 14 between the second element 7b and the second element 7b is welded or brazed, and this joint has a reinforcing effect on the cylindrical mesh member 7, and has a strong mechanical strength compared to the spherical mesh member.
It can withstand handling during equipment assembly work, maintenance, and inspection without causing deformation or damage.

Furthermore, in the microwave resonant cavity shown in FIGS. 4 and 5, the joint 14 between the first element 7a and the second element 7b is connected to the circumferentially inner or circumferential side via the annular member 15.15"i, respectively. The cylindrical mesh member 7 has an even stronger mechanical strength.The first element 7a of the cylindrical mesh member 7 is shown in FIG. The mechanical strength can be increased by joining multiple reinforcing lans 16, for example by spot welding, along the outer circumference of the opening end of the prismatic mesh shown in FIG. Similarly, a mechanically strong microwave resonant cavity can be constructed with respect to the members.

〔Effect of the invention〕

As described above, according to the present invention, the microwave resonant cavity is formed of a flat mesh member, and a cylindrical part with both ends open, and a flat mesh-like closing member for blocking microwaves is joined to one end of the opening. This structure makes it easy to manufacture a single-wave resonant cavity, has strong mechanical strength, and does not deform or break when handled during assembly, maintenance, or inspection of the device. A wave number power source device can be obtained.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view schematically showing a conventional microwave power source device, FIG. 2 is a cross-sectional view schematically showing a microwave power source device according to an embodiment of the present invention, and FIG. FIG. 4, FIG. 5, and FIG. 6 are front views showing microwave resonant cavities according to each embodiment of the present invention, respectively. FIG. 7 is a perspective view showing a microwave resonant cavity according to still another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Magnetron, 2... Magnetron antenna, 3... Waveguide, 4... Vent, 5... Microwave resonance cavity, 6... Cavity wall, 7... Light transmission sexual parts,
7g, 7c...first element, 7b, 7d...second element, 8...power supply port, 9...lamp, 1o...light reflecting surface, 11...cooling fan, 13. 14.17... Joint portion, 15... Annular member. Note that the same reference numerals in the drawings indicate the same parts or similar parts. Agent Masuo Oiwa Figure 1 Figure 1 Figure 3 h Figure 2 1! Fig. 4 7h Fig. 5 Fig. 1/Continued from Fig. 7 Page 1 0 Inventor Hiroshi Ito Kamanai ■ Inventor Yoshizawa Kenji Amaki @ Inventor Komura 5-1 Ofuna, Kakura City, Amaki No. 1 Mitsubishi Electric Co., Ltd. Ofuna Manufacturing 8-1-1 Sakiichi Tsuka Nihonmachi Mitsubishi Electric Co., Ltd. Applied Machinery Research Laboratory 8-1-1 Tsukaguchi Honmachi, Uchisaki City Mitsubishi Electric Co., Ltd. Applied Machinery Research Laboratory

Claims (1)

[Scope of claims] In a microwave discharge light source device having a discharge temperature of 2π steradians or more, the microwave resonant cavity is attached to a first element formed by forming a flat mesh member into a cylindrical shape with openings at both ends, and to one open end of the first element. and a second element consisting of a flat mesh-like blocking part that blocks microwaves inside the first element, and is configured to supply microwave energy from the other open end of the first element. A microwave discharge light source device characterized by: (2) A microwave discharge light source device according to claim 1, wherein the first element has a cylindrical shape. (3) The first element The microwave discharge light source device according to claim 1, wherein the first element and the second element are directly joined by welding. The microwave discharge light source device according to claim 2 or 3, characterized in that a wave resonance cavity is formed. (5) The first element and the second element are brazed together. The microwave discharge light source device according to claim 2 or 3, characterized in that they are joined together to form a microwave resonant cavity. (6) The first element and the second element. and a microwave resonant cavity is formed by joining them via an annular member disposed along the inner circumference of one of the open ends of the first element, or The microwave discharge light source device according to Item 13. (7) An annular member in which the first element and the second element are arranged along the outer circumference of one of the opening ends of the first element. The microwave discharge light source device according to claim 2 or 3, characterized in that the first element and the second element are joined together to form a microwave resonant cavity. Claim 2 or 3, wherein a reinforcing flange is joined to the outer circumferential side of the other open end of the first element in the microwave resonant cavity formed by joining. Microwave discharge light source device.