JPH05182636A - Ultraviolet ray irradiating device - Google Patents

Abstract

PURPOSE:To provide a ultraviolet ray irradiating device, which can improve a lifetime of an optical sensor and which can irradiate the ultraviolet ray efficiently to an object to be irradiated. CONSTITUTION:A ultraviolet ray irradiating device is provided with a high- powered ultraviolet ray generating low-pressure mercury lamp 11, which has a light emitting tube 12 having a flat cross section, and an optical sensor 21, which is provided at a position opposite to a cross directional end of the cross section of the light emitting tube 12 of the low-pressure mercury lamp 11. Or, a ultraviolet ray irradiating device is provided with a high-powered ultraviolet ray generating low-pressure mercury lamp 11 having a light emitting tube 51, which has a flat cross section and which is folded into a U-shape within the surface of the flat direction, and an optical sensor 21, which is provided in a clearance between opposite parts of the light emitting tube 51 of the low- pressure mercury lamp 11, which is folded into a U-shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultraviolet irradiation device for photochemical reaction, for example.

[0002]

2. Description of the Related Art Conventionally, as an ultraviolet irradiation device of this type, as shown in FIG. 7 to FIG. It is known to detect the output of the above, control the output of the ultraviolet ray by this, or detect the deterioration of the arc tube 1 and issue an alarm.

[0003]

However, in the above-mentioned conventional ultraviolet irradiation device, as shown in FIG. 9, the output of the ultraviolet rays emitted from the arc tube is uniform in all directions, so that the photosensor is severely deteriorated. Further, since a part of the ultraviolet rays emitted from the arc tube is blocked, there is a problem that the amount of the ultraviolet rays reflected from the reflector and emitted downward is reduced and the irradiation efficiency is lowered.

The present invention has been made to solve the above-mentioned problems, and an object thereof is to improve the life of the photosensor and to efficiently irradiate an object with ultraviolet light. It is to provide an irradiation device.

[0005]

In order to achieve the above object, the invention of claim 1 has a low-pressure mercury lamp for generating high-power ultraviolet light, which has an arc tube having a flat cross section, and this low-pressure mercury lamp. And an optical sensor provided at a position facing the end of the arc tube in the width direction of the cross section. Further, the invention of claim 2 is a low-pressure mercury lamp for generating high-power ultraviolet light, which has a flat cross-section and has an arc tube folded back in a U-shape in the plane of the flat direction, and the low-pressure mercury lamp. It is characterized in that a light emitting tube of a mercury lamp is folded back into a U shape and provided with an optical sensor provided in a gap between portions facing each other. Further, claim 3
The invention is characterized by using an ultraviolet sensor as the optical sensor.

[0006]

According to the invention of claim 1 configured as described above, since the cross section of the arc tube is formed in a flat shape, the output of ultraviolet rays from the flat surface, which is a surface along the width direction of the cross section. Strong, the output of ultraviolet rays from the end surface in the width direction becomes extremely small. Therefore, the irradiation efficiency can be improved by using the flat surface toward the irradiation target. Also, since the optical sensor is provided at a position facing the end of the arc tube in the width direction, it is not possible to directly detect the amount of ultraviolet rays or the like emitted from the flat surface, but the distribution of ultraviolet rays around the arc tube is known. Therefore, it is possible to indirectly know the output of the ultraviolet rays or the like on the flat surface. Then, since the optical sensor is provided at the position where the output of the ultraviolet rays is small at the end portion in the width direction of the arc tube, it is possible to suppress the deterioration of the optical sensor due to the ultraviolet rays as much as possible, and since it does not block strong ultraviolet rays, Irradiation efficiency can be improved.

Further, in the invention of claim 2 configured as described above, since the optical sensor is provided in the gap between the arc tubes which are folded back in a U shape and face each other, the optical sensor is located on the arc tube side. There is no need to worry about hitting the reflector that covers the entire area and the upper part. Therefore, it can be designed so that the function as a reflection plate can be sufficiently exhibited. Further, in the invention of claim 3, since the ultraviolet sensor is used as the optical sensor, it is possible to detect the intensity of the ultraviolet ray from the arc tube.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the present invention will be described below with reference to FIGS. First, a first embodiment will be described with reference to FIGS.

1 to 3, reference numeral 11 is a low-pressure mercury lamp for generating high-power ultraviolet rays, which has an arc tube 12 having a flat cross section. The low-pressure mercury lamp 11 has been developed in response to the recent demand for higher output and higher density, and in the conventional cylindrical arc tube, the self-absorption of the mercury line becomes remarkable as the input is increased, and it becomes excessive. It overcomes the fact that the UV output decreases when the input is increased. That is, since the length of the flat cross section in the height direction (short axis direction) is short, self-absorption of the mercury line in this direction is small.

Therefore, as shown in FIG. 9, the output of ultraviolet rays from the flat surface, which is a surface along the width direction (long axis direction), becomes high in output and high in density, and the ultraviolet rays from the end surface in the width direction are emitted. Output is very small. With such a structure, for example, in the case of 254 nm ultraviolet rays, the output of ultraviolet rays is rather lowered in the conventional cylindrical arc tube even if the current density (the discharge current divided by the cross-sectional area in the arc tube) is increased. Therefore, it was possible to increase the current density to about 1.6 to 3 A / cm ² , but the current density was 8 A / cm.
It can correspond to high density of up to about ^2, from about 6A /
became UV output of the conventional double is obtained in cm ^2.

Arc tube 12 developed as described above
Is made of synthetic quartz glass having a high ultraviolet transmittance, and has a rectangular cross section with a cross-sectional length of 30 mm in the width direction and a length of 15 mm in the height direction. Further, the arc tube 12 has electrode storage portions 12a at both ends thereof.
Is formed into a cylindrical shape having a diameter of 24 mm. Electrode storage part 1
The axial length of 2a is about 100 to 300 mm.

An anode 13 and a cathode 14 are housed in each electrode housing portion 12a, and the anode 13 and the cathode 1 are housed therein.
4 is fixed by a stem 15 that seals the electrode housing portion 12a. The anode 13 is formed by a circular two-layer coil. For example, a tungsten wire having a wire diameter of 1.2 mm is formed into a first-layer coil tightly wound with an outer diameter of 20 mm and a winding number of 8 turns. The second layer coil is rewound and formed.

The cathode 14 is made of a tungsten coil filament and is located on the back side of the anode 13. The reason why the cathode 14 is located at the back of the anode 13 is to protect the cathode 14 from fast electrons that enter the anode 13. Lead wire 1 is provided for each anode 13 and cathode 14.
6 is connected.

In the arc tube 12, a predetermined amount of mercury or amalgam and an argon gas for starting (13 to 267).
Pa) is enclosed, and an electrode part cooling means (not shown) is provided in each electrode housing part 12a. Further, an ultraviolet sensor 21 is provided at a position facing one end in the width direction of the flat cross section of the arc tube 12. The ultraviolet sensor 21 detects the output of ultraviolet rays by, for example, a photodiode, and is fixed to the side plate 32 of the reflection plate 31.

The reflecting plate 31 reflects the ultraviolet rays emitted from the upper plane of the arc tube 12 downward, and the ultraviolet rays reflected by the reflecting plate 31 are passed through the arc tube 12 again and the object to be illuminated on the lower side. It is designed to irradiate H. The irradiation target H is, for example, a liquid crystal glass substrate supplied for light cleaning or the like. Further, in FIG. 1, reference numeral 41 is a table on which the irradiation object H is placed.

In the ultraviolet irradiation device constructed as described above, a half-wave current component is caused to flow between the anode 13 on one end side and the cathode 14 on the other end side of the low-pressure mercury lamp 11 to discharge during this period, Anode 13 at the other end and cathode 14 at the one end
Inverse half-wave current component is made to flow between and to discharge between them,
By alternately repeating the discharge in this manner, the light is continuously emitted. Such discharge excites a vapor mainly composed of mercury in a low pressure state, and as a result, it emits light in various short wavelength ultraviolet regions of 254 nm and 185 nm of the resonance line of mercury.

Further, by the ultraviolet sensor 21, the arc tube 1
The output of ultraviolet rays from the end portion of the width direction 2 is detected. Since the output of ultraviolet rays around the arc tube 12 has a predetermined distribution as shown in FIG. 6, the output of ultraviolet rays from the end portion of the arc tube 12 in the width direction is used to know the output of ultraviolet rays from the plane. be able to.

According to the ultraviolet irradiating device constructed as described above, since the ultraviolet sensor 21 is provided in the portion where the ultraviolet output is small, the deterioration of the ultraviolet sensor 21 can be prevented. Moreover, since the ultraviolet ray sensor 21 does not block strong ultraviolet rays, the efficiency of ultraviolet ray irradiation can be improved.

Although an ultraviolet sensor is provided as a sensor in the above embodiment, it goes without saying that this sensor may be a sensor that detects other light such as heat. Then, for example, a sensor that detects heat or the like can be used to control the temperature of the arc tube 12.

Next, a second embodiment of the present invention will be described with reference to FIGS. The second embodiment differs from the first embodiment in that the arc tube 51 is formed in a U shape and that the ultraviolet sensor 21 is provided in a gap between the arc tube 51 and the U-shaped folded portion. That is the point. That is,
The arc tube 51 has a flat cross section, and is bent in a U shape in a plane in the flat direction. Also,
The ultraviolet sensor 21 is supported by the top plate 33 of the reflection plate 31 and is arranged in the U-shaped gap of the arc tube 51.
The rest of the configuration is the same as that of the first embodiment, so its explanation is omitted.

According to the ultraviolet irradiating device constructed as described above, since the ultraviolet sensor 21 is arranged in the U-shaped gap of the arc tube 51, the ultraviolet sensor 21 has the reflecting plate 31.
Will not get in the way. Therefore, the shape of the reflection plate 31 can be freely designed so that the reflection efficiency is optimized. Further, since the arc tube 51 is formed in a U shape, the irradiation area is increased and the density of ultraviolet rays is increased. Therefore, it is possible to perform light cleaning of the irradiation target H in a short time.

[0022]

According to the invention of claim 1, since the arc tube is formed to have a flat cross section, irradiation is performed by using a flat surface which is a surface along the width direction toward the object to be irradiated. The efficiency can be improved. Moreover, since the optical sensor is provided at a position facing the end of the arc tube having a small output of ultraviolet light in the width direction, the life of the optical sensor can be extended and strong ultraviolet light is not blocked by the optical sensor. Therefore, the irradiation efficiency of ultraviolet rays can be improved.

Further, according to the second aspect of the invention, since the optical sensor is folded in a U shape and provided in the gap between the portions facing each other, the optical sensor covers the entire side and upper part of the arc tube. There is no need to worry about hitting the reflector. Therefore, the reflector can be designed in a free shape that can sufficiently exhibit the function of the reflector, and thus the irradiation efficiency can be improved. Further, according to the invention of claim 3, since the ultraviolet sensor is used as the optical sensor, the intensity of the ultraviolet ray from the arc tube can be detected, and the irradiation amount of the ultraviolet ray to the irradiation object can be accurately detected. be able to.

[Brief description of drawings]

FIG. 1 is a cross-sectional perspective view of a main part of an ultraviolet irradiation device shown as a first embodiment of the present invention.

FIG. 2 is a plan view showing an arc tube and an ultraviolet sensor of the ultraviolet irradiation device.

FIG. 3 is a side view of an arc tube of the ultraviolet irradiation device.

FIG. 4 is a sectional view of a main part of an ultraviolet irradiation device shown as a second embodiment of the present invention.

FIG. 5 is a plan view showing an arc tube and an ultraviolet sensor of the ultraviolet irradiation device.

FIG. 6 is an explanatory view showing the light distribution of the arc tube of the ultraviolet irradiation device shown in the first and second embodiments of the present invention.

FIG. 7 is a perspective view showing a main part of an ultraviolet irradiation device shown as a conventional example.

FIG. 8 is a plan view of an arc tube of the ultraviolet irradiation device.

FIG. 9 is an explanatory view showing light distribution of an arc tube of the ultraviolet irradiation device.

[Explanation of symbols]

 11 Low-power mercury lamp for generating high-power ultraviolet rays 12, 51 Arc tube 21 Optical sensor (ultraviolet sensor)

Claims (3)

[Claims] 1. A low-pressure mercury lamp for generating high-power ultraviolet light, which has a light-emitting tube having a flat cross section, and a low-pressure mercury lamp provided at a position facing the end of the light-emitting tube in the width direction of the light-emitting tube. An ultraviolet irradiation device comprising an optical sensor. 2. A low-pressure mercury lamp for generating high-power ultraviolet light, which has a flat cross-section and has an arc tube folded back in a U-shape in the plane of the flat direction, and the light emission of this low-pressure mercury lamp. An ultraviolet irradiation device, comprising: an optical sensor, which is provided in a gap between portions of the tube that are folded back into a U shape and face each other. 3. The ultraviolet irradiation device according to claim 1, wherein the optical sensor is an ultraviolet sensor.