JP5287928B2 - Excimer lamp - Google Patents

Description

  The present invention relates to an excimer lamp in which a reflection film is formed in a discharge vessel, and more particularly to an excimer lamp in which a light extraction port for light monitoring is formed in the reflection film.

Conventionally, an excimer lamp is known in which a reflection film made of silica-based fine particles that reflect ultraviolet light is formed on a portion of the inner surface of the discharge vessel except the light emitting surface. In such a lamp, on the outer surface of the light emitting surface of the discharge vessel, in order to perform the original function of extracting light, for example, a mesh-like light transmissive electrode coated with gold paste in a lattice shape is used. ing.
On the other hand, the external electrode formed on the outer surface of the non-light emitting surface that does not extract the light facing the light emitting surface does not need to be functionally light transmissive, but in many cases, the manufacturing process is simplified. From the standpoints of, for example, the stability of discharge generated in the discharge vessel, and the like, a light-transmitting electrode is used as it is in the same manner as the light emitting surface.
By the way, in the excimer lamp in various ultraviolet light irradiation apparatuses, since the stable emission of ultraviolet light is required, the amount of the ultraviolet light is monitored. A daylighting port is formed in part, and the ultraviolet light taken out from the daylighting port is monitored.
Such a technique is known, for example, in Japanese Patent Application Laid-Open No. 2010-225343.

This prior art is shown in FIGS. 7, 8 and 9. FIG. 7 is a top view of the excimer lamp, FIG. 8 is a cross-sectional view taken along line AA in FIG. 7, and FIG. 9 is a cross-sectional view taken along line BB in FIG. In the figure, an excimer lamp 20 has a discharge vessel 21 made of quartz glass or the like. On the outer surface of the discharge vessel 21, a pair of light-transmitting external electrodes 22 and 23 formed in a mesh shape with gold paste or the like are formed to face each other. A reflective film 24 is formed on the inner surface of the discharge vessel 21 except for the light emitting surface.
A daylight opening 25 is formed in a part of the reflection film 24, and an optical monitor 26 is disposed above it to monitor the ultraviolet light emitted from the discharge vessel 21.
In this conventional example, a solid electrode 27 is formed at the ends of the external electrodes 22, 23, and a conductor 28 as a starting auxiliary electrode is formed in the discharge vessel 21.

By the way, in the said prior art, since the outline 25a of the lighting port 25 formed in the reflective film 24 overlaps with the strand 23a of the mesh-shaped light transmissive electrode 23 linearly and continuously, it is formed. When a voltage is applied between the external electrodes 22 and 23, as shown in FIG. 10, the electric field tends to concentrate on the edge portion 24a of the reflective film 24 that forms the outline 25a of the lighting port 25 inside the discharge vessel 21 as shown in FIG. The discharge X tends to concentrate on the edge portion 24a.
For this reason, the discharge between the external electrodes 22 and 23 becomes unstable, and when the amount of ultraviolet light extracted from the lighting port 25 is detected by an optical monitor, a number of peaks are generated in the detected signal value and become noise. There was a problem that stable ultraviolet light could not be monitored.
Further, since the discharge concentrates at the edge portion 24a of the reflective film 24, the discharge is less likely to occur near the center of the lighting port 25, and even if a discharge occurs, the discharge becomes extremely weak. For this reason, there is a problem in that the amount of ultraviolet light extracted from the light outlet 25 is reduced, and the amount of light detected by the optical monitor is estimated to be low.

JP 2010-225343 A

  The present invention has been made in view of the above-mentioned problems of the prior art, and a pair of mesh-like light transmissive external electrodes are provided on the outer surface of the discharge vessel, and the inner surface of the discharge vessel is provided on the inner surface of the discharge vessel. In an excimer lamp in which a reflecting film is formed and a lighting port for light monitoring is formed on the reflecting film, discharge does not concentrate at the edge portion of the reflecting film that forms the contour line of the lighting port. Thus, a structure in which stable discharge is maintained in the discharge vessel and the amount of ultraviolet light flux from the lighting port is not reduced is provided.

  In view of the above-described problems of the prior art, in the present invention, the contour line of the light-monitoring aperture for the light monitor formed on the reflective film provided in the discharge vessel is a mesh-like light provided on the outer surface of the discharge vessel. It is characterized in that it does not overlap linearly with the strands of the transmissive electrode.

  By adopting such a configuration, the discharge does not concentrate on the edge portion of the reflective film that forms the contour line of the daylighting port, and a uniform discharge is generated over the entire daylighting port, and ultraviolet light from the daylighting port is generated. Therefore, a normal light monitor can be achieved.

1 is a top view showing a configuration of an excimer lamp that is a first embodiment of the present invention. BB sectional drawing of FIG. The A section enlarged view of FIG. 2 shows a second embodiment of the present invention. 3 shows a third embodiment of the present invention. The fluff which shows the effect of this invention. The top view of a prior art. AA sectional drawing of FIG. BB sectional drawing of FIG. The A section enlarged view of FIG.

FIG. 1 is a top view showing a first embodiment of an excimer lamp according to the present invention, FIG. 2 is a sectional view taken along the line BB, and FIG. 3 is an enlarged view of a portion A in FIG.
In the figure, on the outer surface of the discharge vessel 2 of the excimer lamp 1, for example, mesh-like light transmissive electrodes 3 and 4 in which gold paste is applied in a grid pattern are provided. A reflective film 5 is formed on the inner surface of the discharge vessel 2 except for the light irradiation surface 2a. A light outlet 6 for light monitoring is formed at one end of the reflecting film 5 on the non-light emitting surface 2b opposite to the light emitting surface 2a.
The lighting port 6 may have a shape opened at the end of the reflective film 5 as shown, or may be an independent opening without being opened.
In particular, as is apparent from FIG. 3, the contour line 6a of the daylighting port 6 is shifted so as not to overlap with the strand 4a of the mesh-like light transmissive electrode 4 in a straight line. ing.

  In order to prevent the contour line 6a of the lighting port 6 and the element wire 4a of the external electrode 4 from overlapping in a straight line, the shape of the contour line 6a of the lighting port 6 is as shown in FIG. It may be non-linear, for example, a semicircular shape, or may be formed such that the strand 4a of the external electrode 4 forms an angle with the axis of the discharge vessel 2 as shown in FIG. May be.

  In the above embodiment, the solid electrodes 7 are provided at the ends of the external electrodes 3 and 4, and the starting auxiliary electrode 8 is formed on the inner surface of the discharge vessel 2 corresponding to the ends. Although illustrated, these are not necessarily provided.

Experiments were performed to verify the effects of the present invention.
<Invention lamp>
As the lamp of the present invention, as shown in FIG. 1, the light emission length is 1540 mm, xenon gas is sealed in 0.05 MPa in the discharge space, the lighting port 6 has a substantially rectangular shape, and the outline 6 a is the outer electrode 4. What was made not to overlap with the strand 4a linearly was used.
<Comparative lamp>
As a comparative example lamp, as shown in FIG. 7, a lamp having a structure in which the outline 25 a of the lighting port 25 linearly overlaps the strand 23 a of the external electrode 23 was prepared.

These lamps were lit under the conditions of a lighting frequency of 50 KHz and an input power of 300 W. And the result of having measured the light quantity of the ultraviolet light of each lamp | ramp is shown by FIG. In the figure, the vertical axis is a signal value representing the amount of ultraviolet light, and the horizontal axis is time.
In the comparative lamp, the measured value on the light monitor was low, and many peak values occurred in time, and the discharge was unstable. This was because the discharge was concentrated on the edge of the reflective film. Is due to.
On the other hand, in the lamp of the present invention, it can be seen that the signal value indicating the light amount is stable without decreasing.

  As described above, in the present invention, the contour line of the daylighting port formed in the reflective film provided on the inner surface of the discharge vessel is made not to overlap linearly and continuously with the strand of the mesh-like external electrode. Therefore, the discharge does not concentrate on the edge part of the reflection film forming the daylighting port, and stable discharge can be realized in the discharge vessel, and a uniform discharge is generated over the entire daylighting port, and accurate ultraviolet light is generated. The effect is that monitoring is possible.

  In the description of the above embodiment, the discharge vessel 2 has been described as having a rectangular tube shape. However, the present invention is not limited to this, and it is needless to say that various shapes such as a round tube shape can be adopted.

DESCRIPTION OF SYMBOLS 1 Excimer lamp 2 Discharge vessel 2a Light emission surface 2b Non-light emission surface 3 Light transmissive external electrode (light emission surface side)
4 Light transmissive external electrode (non-light emitting surface side)
4a Wire 5 Reflective film 6 Lighting port 6a Contour line

Claims (1)

A pair of mesh-like light-transmitting external electrodes are provided on the outer surface of the discharge vessel, a reflection film is formed on the inner surface of the discharge vessel, and a lighting port for light monitoring is formed on the reflection film. In the excimer lamp
An excimer lamp, wherein the contour line of the daylighting port is formed so as not to overlap linearly with the wire of the mesh-shaped external electrode.

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