JP2001052645A - Ultraviolet ray generating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently generate ultraviolet rays having optimum wavelength for a pasteurizing device or a hazardous substance decomposing device without using mercury. SOLUTION: A vacuum vessel 3 is equipped with an electron beam source to generate electron beam 2 and coupled through a beam inlet 5 with the side of a sealed vessel 1 of hollow inside made of a dielectric substance transmitting ultraviolet rays, and the vessel 1 is filled with an excitation gas 4, which is irradiated with electron beam. Example of the gas 4 is a mixture of a rare gas such as xenon, krypton, argon, and oxygen or any halogen gas or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultraviolet ray generator for generating ultraviolet light from a mixed gas such as oxygen and a rare gas such as xenon by an electron beam.

[0002]

2. Description of the Related Art Conventionally, ultraviolet rays have been used for sterilization, disinfection, and decolorization of water and sewage, deodorization and decolorization of industrial water, bleaching of pulp, and sterilization of medical equipment. A mercury lamp or an excimer lamp is used as a light source for generating such ultraviolet light. A low-pressure mercury lamp generates ultraviolet light having a wavelength of 254 nm or 185 nm, and the excimer lamp emits xenon, krypton, and argon as an excitation medium. 172n
It is known to generate ultraviolet rays having wavelengths of m, 146 nm and 126 nm.

[0003]

FIG. 7 shows the relationship between the ultraviolet radiation and the lethal action spectrum and DNA absorption spectrum of Escherichia coli. Since ultraviolet radiation with a wavelength of about 250 nm is the most efficient, a low-pressure mercury lamp with a wavelength of 254 nm is used for a sterilizer using ultraviolet light or the like. However, since the above-mentioned sterilizer using a low-pressure mercury lamp uses mercury, it can be used for sewage treatment and the like, but is dangerous for sterilization, disinfection, decolorization, etc. of air and drinking water. Therefore, it was difficult to use.

Excimer lamps that use xenon without using mercury are easily absorbed by air or oxygen contained in water because of their wavelengths, and are therefore suitable for sterilization, disinfection, decolorization, etc. of air and drinking water. Was difficult to use.

On the other hand, a low-pressure mercury lamp having a wavelength of 185 nm is used for an apparatus for decomposing harmful substances using ultraviolet rays. This is because, as shown in FIG. 8, the absorption of harmful substances such as organic chloride-based trichlorethylene is concentrated around the wavelength of 200 nm, which is suitable for breaking the interatomic bond. In other words, ultraviolet light having a wavelength of 185 nm is effective for decomposing harmful substances such as trichloroethylene.

However, since mercury is also used, it is necessary to pay attention to the use environment. In addition, since the emission ratio of a mercury lamp at 185 nm is lower than that at 254 nm, it is inefficient to use a low-pressure mercury lamp in an apparatus for decomposing harmful substances using ultraviolet rays. Furthermore, an excimer lamp using noble gas such as xenon without using mercury could not be used due to wavelength.

[0007] The present invention has been proposed to solve the above-mentioned problems of the prior art, and its object is to use an optimal wavelength for a sterilizer or a harmful substance decomposer without using mercury. An object of the present invention is to provide an ultraviolet ray generator capable of generating ultraviolet rays with high efficiency.

[0008]

According to a first aspect of the present invention, there is provided an ultraviolet ray generating apparatus, wherein an electron beam generating source is provided in a first container made of a dielectric material that transmits ultraviolet rays. The second container provided is connected via a beam introduction port, and the first container is filled with an excitation gas containing a rare gas as a main component and added with oxygen or a halogen gas. The container is configured to be irradiated with an electron beam.

According to the first aspect of the present invention, the electron beam incident on the first container reacts with the excitation gas filled in the first container to form a plasma. This plasma generates ultraviolet light. In addition, by using a predetermined excitation gas containing a rare gas as a main component and adding oxygen or a halogen gas as an excitation gas, it is possible to select an ultraviolet ray having a wavelength optimal for a sterilizing apparatus or a harmful substance decomposition apparatus without using mercury. Can be generated.

According to a second aspect of the present invention, there is provided an ultraviolet ray generating apparatus in which a second container having an electron beam generating source therein is inserted into a first container having a dielectric window which transmits ultraviolet rays through a beam introducing port. And connecting the first container to an excitation gas containing a rare gas as a main component and adding oxygen or a halogen gas, and irradiating the first container with an electron beam from the second container. It is characterized by the following.

According to the second aspect of the present invention having the above structure, not only the same operation and effect as those of the first aspect can be obtained, but also a metal having a dielectric window which transmits ultraviolet rays. The use of the container has the advantage that the gas can be easily exchanged and the emission wavelength can be varied by selecting the gas.

According to a third aspect of the present invention, in the ultraviolet ray generating device according to the first or second aspect, the beam introduction port is provided with a predetermined metal in a titanium metal thin film, a polyimide thin film, or a silicon thin film. It is characterized by being composed of a deposited member. According to a fourth aspect of the present invention, in the ultraviolet ray generating device according to any one of the first to third aspects, the beam introduction port is formed in a pinhole or slit shape. is there.

[0013] Claims 3 and 4 having the above configuration.
According to the invention described in (1), by optimizing the material or shape of the beam inlet, the excitation gas flows from the first container to the second container, and the pressure in the second container increases. Can be prevented.

According to a fifth aspect of the present invention, there is provided an ultraviolet generating apparatus according to any one of the first to fourth aspects,
An exhaust device for maintaining the degree of vacuum in the container at 1 Pa or less is provided in the second container. According to the invention described in claim 5 having the above configuration, the degree of vacuum in the second container can be maintained at 1 Pa or less.
It is possible to extend the life of the electron beam source, and to prevent the excitation gas from flowing from the first container to the second container through the beam introduction port and increasing the pressure in the second container. It can be prevented with higher accuracy.

According to a sixth aspect of the present invention, there is provided the ultraviolet ray generating device according to any one of the first to fifth aspects, wherein:
An apparatus for replenishing an excitation gas is provided in the first container. Claim 6 having the above configuration.
According to the invention described in (1), since the apparatus for replenishing the first container with the excitation gas is provided, the gas density of the excitation gas in the first container can always be kept at the optimum value.

According to a seventh aspect of the present invention, there is provided an ultraviolet ray generator, wherein an electron beam source is disposed in a closed container having a dielectric window through which ultraviolet rays pass, and an electron beam generated from the electron beam source is moved along a trajectory of the electron beam. And a nozzle for blowing an excitation gas containing a rare gas as a main component and added with oxygen or a halogen gas. According to the seventh aspect of the present invention having the above-described configuration, not only the same operation and effect as those of the first or second aspect of the invention are obtained, but also a dielectric window that transmits ultraviolet light is provided. Since the electron beam generation source is disposed in the vacuum vessel, the configuration of the device is further simplified.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention (hereinafter, referred to as embodiments) will be specifically described below with reference to the drawings.

[1. First Embodiment] The ultraviolet ray generator of the present embodiment is configured as shown in FIG. That is, a dielectric (eg, quartz glass,
A vacuum container 3 provided with an electron beam generating source for generating an electron beam 2 is connected to a side portion of a closed container 1 having a hollow inside made of MgF ₂ or the like via a beam introduction port 5. . Further, an excitation gas 4
Is filled.

As the beam introducing port 5, a metal thin film such as titanium, a polyimide thin film or a silicon thin film obtained by depositing metal gold or the like is used. Also,
As the excitation gas 4, a mixture of a rare gas such as xenon, krypton, or argon and oxygen or a halogen gas is used. In addition, as the halogen gas, chlorine,
Fluorine or the like is used. The mixing ratio of a rare gas such as argon to oxygen is desirably 0.1% oxygen to 99.9% of a rare gas such as argon, and the mixing ratio of a rare gas such as argon and a halogen gas is preferably argon. Noble gas 80 etc.
% Is preferably 20% with respect to%.

For example, when a gas obtained by adding oxygen to krypton gas is used as the excitation gas (Kr: 99.9%,
O ₂ : 0.1%), as shown in FIG. 2, it is possible to generate ultraviolet rays having a wavelength of about 250 nm, which is effective for sterilization, disinfection and decolorization, without using mercury. Also, as the excitation gas,
In the case where a gas obtained by adding oxygen to argon gas is also used (A
r: 99.9%, O ₂ : 0.1%), as shown in FIG. 3, it is possible to generate ultraviolet rays near 200 nm which is effective in decomposing harmful substances such as trichlorethylene without using mercury. it can.

In the ultraviolet ray generating apparatus of the present embodiment having the above-described configuration, the electron beam 2 is introduced into the closed vessel 1 through the beam inlet 5 from the vacuum vessel 3 provided with an electron beam source. You. Then, the electron beam 2 incident on the closed container 1 reacts with the excitation gas 4 filled in the closed container 1 to form a plasma 6, which generates ultraviolet rays 7. The generated ultraviolet light 7 propagates to the outside of the sealed container 1 made of a dielectric material that transmits ultraviolet light, and is used for various purposes.

Further, when a gas obtained by adding oxygen to krypton gas is used as the excitation gas, an ultraviolet ray of about 250 nm can be generated, so that the optimum wavelength for a sterilizer or the like can be obtained without using mercury. UV light can be generated. In addition, when a gas obtained by adding oxygen to an argon gas is used as the excitation gas, ultraviolet light having a wavelength around 200 nm can be generated. Ultraviolet light can be generated. As described above, according to the present embodiment, a versatile ultraviolet light generator can be provided by changing the composition of the excitation gas to be filled with the same device.

[2. Second Embodiment] The ultraviolet ray generating device of the present embodiment is a modification of the first embodiment, and is configured as shown in FIG. That is, a vacuum container 3 having an electron beam generating source for generating the electron beam 2 is connected to a side portion of a closed container 11 having upper and lower surfaces of a dielectric window 10 that transmits ultraviolet rays through a beam introduction port 5. Have been. The closed vessel 1 is filled with an excitation gas 4. The other configuration is the same as that of the first embodiment, and the description is omitted. In addition, quartz glass can be used as a material of the dielectric window 10. Further, as in the first embodiment, a mixture of a rare gas such as xenon, krypton, and argon and oxygen or a halogen gas is used as the excitation gas 4.

In the ultraviolet ray generator of the present embodiment having the above-described configuration, the electron beam 2 is introduced into the closed vessel 1 through the beam inlet 5 from the vacuum vessel 3 provided with the electron beam source. You. Then, the electron beam 2 incident on the closed container 1 reacts with the excitation gas 4 filled in the closed container 1 to form a plasma 6, which generates ultraviolet rays 7. The generated ultraviolet light 7 propagates from the dielectric window 10 that transmits ultraviolet light to the outside of the sealed container 11 and is used for various purposes. In particular, by using a metal container provided with the dielectric window 10, gas can be easily exchanged,
There is an advantage that the wavelength can be easily changed by gas exchange.

Also in this embodiment, the excitation gas 4
Since a mixture of a rare gas such as xenon, krypton, or argon and oxygen or a halogen gas is used as in the first embodiment, the same device is used to change the composition of the excitation gas to be filled. Thus, a versatile ultraviolet light generator can be provided.

[3. Third Embodiment] An ultraviolet generator according to the present embodiment is a modification of the above-described second embodiment, and is configured as shown in FIG. That is, a vacuum vessel 3 provided with an electron beam generating source for generating an electron beam 2 is provided on a side of a closed vessel 11 provided with a dielectric window 10 that transmits ultraviolet light, by a beam introduction system comprising a pinhole 21 or a slit. It is connected through the mouth. The closed vessel 11 is filled with the excitation gas 4. Further, an electron gun 2 for generating electrons is provided in the vacuum vessel 3.
2 and an accelerating electrode 23 for accelerating the generated electrons to a predetermined energy. In addition, an exhaust device 24 is connected to the vacuum container 3, and the degree of vacuum in the vacuum container is set to 1
You may comprise so that it may maintain Pa or less. The other configuration is the same as that of the second embodiment, and the description is omitted.

In the ultraviolet ray generating apparatus of the present embodiment having the above-described configuration, not only the same operation and effect as in the second embodiment can be obtained, but also the beam introduction port is constituted by the pinhole 21 or the slit. Therefore, it is possible to prevent the excitation gas 4 from flowing into the vacuum vessel 3 on the electron beam source side.

In order to extend the life of the electron gun 22,
The degree of vacuum in the container containing the electron gun must be 1 Pa or less. On the other hand, in order to increase the brightness of the generated ultraviolet light, the gas density of the excitation gas irradiated with the electron beam must be 1
It is desirable to make it equivalent to 000 to 3,000,000 Pa. Therefore, when the exhaust device 24 is connected to the vacuum container 3, the vacuum device 3 can be maintained at a degree of vacuum of 1 Pa or less by the exhaust device 24. It is possible to prevent the pressure from rising due to the flow of the excitation gas 4 into the vacuum container 3 on the side with higher precision.

[4. Fourth Embodiment] The ultraviolet ray generator of the present embodiment is configured as shown in FIG. That is, an electron gun 32 as an electron beam source and an accelerating electrode 33 for accelerating generated electrons to a predetermined energy are arranged in a vacuum vessel 30 having a dielectric window 31 that transmits ultraviolet rays. Nozzle 34 for blowing out an excitation gas on the trajectory of electron beam 2 generated from the electron beam source
, And the ultraviolet rays 7 are generated by generating the plasma 6 by the electron beam 2.

The degree of vacuum of the vacuum vessel 30 is 1 Pa
In order to keep the following, the exhaust device 35 may be provided to be connected to the vacuum container 30. Further, the excitation gas discharged by the exhaust device 35 may be returned to the inside of the vacuum vessel 30 again so that the excitation gas can be reused as the excitation gas.

In the ultraviolet ray generator of the present embodiment having the above-described configuration, not only the same operation and effect as those of the above-described embodiments can be obtained, but also a vacuum vessel having a dielectric window that transmits ultraviolet rays. Since the electron beam generation source is disposed inside, the configuration of the device is further simplified.

[5. Other Embodiments] Note that the present invention is not limited to the above-described embodiment, and the excitation gas filled in the closed container flows out of the beam introduction port to the outside or the vacuum container, and the inside of the closed container is In order to prevent the pressure from dropping, a device for replenishing the closed vessel with the excitation gas may be provided.

[0033]

As described above, according to the present invention, it is possible to provide an ultraviolet ray generator capable of efficiently generating ultraviolet rays having a wavelength optimal for a sterilizer or a harmful substance decomposer without using mercury. Becomes

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a configuration of a first embodiment of an ultraviolet ray generator according to the present invention.

FIG. 2 is a view showing an ultraviolet spectrum when a gas obtained by adding oxygen to krypton gas is used as an excitation gas.

FIG. 3 is a view showing an ultraviolet spectrum when a gas obtained by adding oxygen to an argon gas is used as an excitation gas;

FIG. 4 is a schematic diagram showing the configuration of a second embodiment of the ultraviolet ray generator according to the present invention.

FIG. 5 is a schematic diagram showing the configuration of a third embodiment of the ultraviolet ray generator according to the present invention.

FIG. 6 is a schematic diagram showing a configuration of a fourth embodiment of the ultraviolet ray generator according to the present invention.

FIG. 7 is a diagram showing the relationship between ultraviolet radiation and the lethal action spectrum and DNA absorption spectrum of Escherichia coli.

FIG. 8 is a diagram showing the relationship between ultraviolet radiation and the absorption spectrum of trichloroethylene.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 11 ... Closed container 2 ... Electron beam 3 ... Vacuum container 4 ... Excited gas 5 ... Plasma 6 ... Beam introduction port 7 ... Ultraviolet 10 ... Dielectric window 21 ... Pinhole 22 ... Electron gun 23 ... Acceleration electrode 24 ... Exhaust device Reference Signs List 30 vacuum chamber 31 dielectric window 32 electron gun 33 accelerating electrode 34 nozzle 35 exhaust device

Claims (7)

[Claims] 1. A first container made of a dielectric material that transmits ultraviolet light, a second container having an electron beam generation source therein.
Are connected via a beam inlet, and the first container is filled with an excitation gas containing a rare gas as a main component and oxygen or a halogen gas added thereto. Electrons are transferred from the second container to the first container. An ultraviolet ray generator, wherein the ultraviolet ray generator is configured to irradiate a beam. 2. A first device having a dielectric window that transmits ultraviolet light.
A second container provided with an electron beam source therein is connected via a beam inlet to the container, and an excitation gas containing a rare gas as a main component and oxygen or a halogen gas added thereto is added to the first container. An ultraviolet ray generator, wherein the ultraviolet ray generator is filled and irradiated with an electron beam from the second container to the first container. 3. The method according to claim 1, wherein the beam introduction port is formed of a member obtained by depositing a predetermined metal on a titanium metal thin film, a polyimide thin film, or a silicon thin film. The ultraviolet generator according to the above. 4. The ultraviolet ray generating apparatus according to claim 1, wherein said beam introducing port is formed in a pinhole or slit shape. 5. An ultraviolet ray generator according to claim 1, wherein an exhaust device for maintaining a degree of vacuum in the container at 1 Pa or less is provided in the second container. apparatus. 6. The ultraviolet generator according to claim 1, wherein a device for replenishing the excitation gas is provided in the first container. 7. An electron beam source is provided in a sealed container provided with a dielectric window that transmits ultraviolet light, and the orbit of an electron beam generated from the electron beam source is mainly composed of a rare gas containing oxygen or oxygen as a main component. An ultraviolet ray generator comprising a nozzle for blowing an excitation gas to which a halogen gas is added.