JPS63998A - Microwave discharge light source - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Prior art] As a prior art for this process, for example, Japanese Patent Publication No. 59-603
There is a method shown in Publication No. 2, in which a high-frequency electromagnetic field is supplied to a cavity resonator by a waveguide, a resonance state is formed in the cavity resonator, and the cavity is When lighting the electrodeless lamp installed in the resonator, the portion of the cavity resonator outside the connection portion with the waveguide is made of a metal mesh.

For example, based on the structure shown in Japanese Patent Publication No. 59-6032, the same applicant has proposed the structure shown in FIGS. 2 and 3.

These FIGS. 2 and 3 are the technology that forms the background of the invention of this application, and will be explained below.

That is, in FIG. 2, which is a partially enlarged view of a cylindrical metal mesh used in the device shown in FIG. 3, which is a sectional view showing a microwave discharge light source device, (1) is a magnetron, and (2) is a cylindrical metal mesh. is a magnetron antenna, (3) is a waveguide, (4) is a vent provided in the waveguide (3), (5
) is a microwave resonant cavity consisting of a cavity wall (6) connected to the end of the waveguide (3) and a light-transmitting member (7) made of a cylindrical metal mesh having a square mesh opening. ) is the - part of the light-transmitting member (7),
a is the mesh maximum pitch, and b is the mesh wire diameter. (
8) is a power feed port provided in the cavity wall (6), and the waveguide (3)
) to feed microwaves into the microwave resonant cavity (5). (9) is a microwave resonant cavity (
5) A spherical electrodeless lamp disposed inside, αω is a lamp support extending from the outer wall of the lamp (9), and the lamp (9) is fixed to the cavity wall (6) with the lamp fixing screw (11). are doing. (12) is a light reflecting plate that reflects the light emitted from the microwave resonant cavity (5), and (13) is a magnetron (1).
) and a cooling fan that cools the lamp (9), and (14) is a box that covers the whole.

What is shown in FIGS. 3 and 2 is constructed as described above,
Microwaves oscillated by the magnetron (1) are radiated into the waveguide (3) through the magnetron antenna (2). This microwave propagates through the waveguide (3) and feeds into the feed port (8).
) into the microwave resonant cavity (5), forming a microwave electromagnetic field within the cavity (5). This microwave electromagnetic field causes the lamp (9) to discharge and emit light. This light is transmitted through the square opening of the cylindrical metal mesh into the cavity (
5), is reflected by the reflecting plate (12), and is emitted forward. - Since the magnetron (1) and lamp (9) need to be cooled, the fan (13)
The air is blown to cool the magnetron (1), and the air is then exhausted through the opening of the cylindrical metal mesh after cooling the lamp (9) through the ventilation port (4) and the power supply port (8).

[Problem that the invention seeks to solve]

In the light-transmitting member having the above structure, the opening is square, so the mechanical strength is weak and the aperture ratio is insufficient. For this reason, during the manufacturing process and lamp replacement work, for example, when handling a cylindrical transparent member, it may become deformed or damaged. This was insufficient for cooling.

The present invention has been made to solve these problems. For example, it prevents a light-transmitting member made of a cylindrical metal mesh from being deformed or damaged, and allows sufficient light to pass through without transmitting microwaves. Another object of the present invention is to obtain a microwave discharge light source device that can sufficiently cool a lamp.

[Means for solving problems]

The microwave discharge light source device according to this invention forms a microwave resonant cavity in which the opening of a light-transmitting member made of a metal mesh has a regular hexagonal shape.

[Effect]

In this invention, the mechanical strength is increased so that deformation and breakage can be prevented, and the aperture ratio is improved so that sufficient transmission of light and sufficient cooling of the lamp can be obtained.

〔Example〕

FIG. 1 is a partially enlarged view of a cylindrical metal mesh showing an embodiment of the present invention. In the figure, a is the maximum mesh pitch, and b is the mesh wire diameter. This will be explained in comparison with FIG. 2. The function of the cylindrical metal mesh is to form a microwave resonant cavity, retain its shape and prevent the transmission of microwaves to the outside and maximize the transmission of light. In addition, the amount of microwave leakage to the outside is determined by the maximum pitch of the mesh, so if the opening of the mesh is square or regular hexagon, the maximum mesh pitch a
When compared with the mesh wire diameter being the same, the aperture ratio is (1-, /T(b/a)) in the case of a square.
”, for regular hexagon: (1-74(b/a))”
becomes. Normally, approximately a-1.0M and b-0.1mm are practical, and the aperture ratio at this time is 73.7X for a square, 78.2X for a regular hexagon, and the regular hexagon is better. Approximately 6z opening rate is large.

That is, for the same amount of microwave leakage, when the mesh opening shape is a regular hexagon, the aperture ratio, that is, the transmission of light, is about 6 larger than when the mesh opening shape is square.

Incidentally, in the above description, the case where the cylindrical mesh opening shape is a regular hexagon is described, but it goes without saying that the present invention can also be applied to cavity shapes other than the cylindrical shape.

〔Effect of the invention〕

As explained above, this invention maintains the shape of the microwave resonant cavity and prevents deformation and damage by making the mesh opening of the light-transmitting member made of metal mesh or the like into a regular hexagon. This has the effect of preventing leakage of microwaves, effectively emitting light to the outside, and increasing the amount of air, so that the lamp can be sufficiently cooled.

[Brief explanation of the drawing]

FIG. 1 is a partially enlarged view of a mesh showing an embodiment of the present invention, FIG. 2 is a partially enlarged view of a mesh proposed by the same applicant, and FIG. 3 is a partially enlarged view showing a mesh having a cylindrical metal mesh. FIG. 2 is a sectional view showing a microwave discharge light source device. In the figure, (3) is a waveguide, (5) is a microwave resonant cavity, (7) is a light-transmitting member, (71) and (72) are part of the light-transmitting member, and (8) is a power supply. Mouth, (9) is a lamp,
a is the mesh maximum pitch, and b is the mesh wire diameter. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (2)

[Claims] (1) A microwave resonant cavity to which microwaves are supplied from a waveguide through a power supply port and has a light-transmitting member on at least a part of the wall surface, and a lamp disposed within this microwave resonant cavity. and a sum of solid angles extending from one point of the lamp to the light transmitting and collecting member side is 2π stera or more, wherein the light transmitting member is composed of a regular hexagonal metal mesh. Wave discharge light source device. (2) The microwave discharge light source device according to claim 1, wherein the microwave resonant cavity has a cylindrical outer shape.