JP2023059671A - Excimer lamp and deactivation device - Google Patents

Abstract

To provide an excimer lamp and a deactivation device that are suitable to deactivate bacteria or virus in the space while securing the safety for humans and animals.SOLUTION: An excimer lamp includes a discharge container in which noble gas and halogen are sealed as a light-emitting gas, and a pair of a first electrode and a second electrode that generate dielectric barrier discharge inside the discharge container. The noble gas is krypton (Kr) and the halogen is chlorine (Cl). The partial pressure (Ph/Pr) of the atom pressure (Ph) of the halogen to the atom pressure (Pr) of the noble gas is 0.05% or more and less than 1%. The discharge container internally includes a discharge formation region that exists between the first electrode and the second electrode and causes discharge, and a non-discharge region that communicates with the discharge formation region and does not cause discharge. When the spatial volume of the whole inside of the discharge container is Va [mm3] and the spatial volume of the discharge formation region is Vd [mm3], the spatial volume ratio (Vd/Va) of the discharge formation region is 70% or less.SELECTED DRAWING: Figure 1

Description

The present invention relates to an excimer lamp in which a rare gas and a halogen are enclosed in a discharge vessel and a deactivation device.

2. Description of the Related Art Conventionally, an excimer lamp is known in which a rare gas and a halogen are sealed as a light emission gas.
An excimer lamp in which a rare gas and a halogen are enclosed has a unique emission wavelength depending on the combination thereof. For example, a combination of rare gases such as xenon (Xe) and krypton (Kr) and halogens such as chlorine (Cl) and bromine (Br) exhibits various emissions with central wavelengths of 200 nm to 300 nm.
In particular, in recent years, it has been found that ultraviolet light with a wavelength of 200 nm or more and less than 240 nm is highly safe for humans and animals, and excimer lamps having a peak wavelength of 200 nm or more and less than 240 nm are attracting attention. . For example, Patent Document 1 discloses a KrCl excimer lamp (center wavelength: 222 nm) in which krypton (Kr) and chlorine (Cl) are enclosed as emission gases, and a lamp in which krypton (Kr) and bromine (Br) are enclosed as emission gases. Virus inactivation using a KrBr excimer lamp (central wavelength 207 nm) is described.

The unique emission wavelength obtained by such a combination of rare gas and halogen originates from the emission of excited dimers (exxiplexes) formed by rare gas atoms and halogen atoms. is expected to be applied.
As an example, a case where krypton (Kr) is used as the rare gas and chlorine (Cl) is used as the halogen will be described with reference to FIG. As shown in FIG. 16, krypton (Kr) present in the discharge forming region A is excited or ionized by electrons emitted by the discharge formed in the discharge forming region A, and is present in the discharge forming region A. Collision with chlorine (Cl) produces KrCl ^* (a krypton chloride exciplex). This KrCl ^* is an extremely unstable compound, and separates into krypton (Kr) and chlorine (Cl) in a short period of time, and unique luminescence (excimer luminescence) L is generated at that time.

Japanese Patent No. 6847053

An excimer lamp in which a rare gas and a halogen are enclosed in a discharge vessel exhibits a characteristic excimer luminescence derived from the luminescence of an excited dimer (exxiplex). It can happen. For example, in a KrCl excimer lamp, in addition to the generation of KrCl ^* (krypton chloride exciplex), when excited chlorine atoms collide with each other to cause specific chlorine luminescence to generate an emission band at a wavelength of 240 nm or more. There is Ultraviolet light with a wavelength of 240 nm or more has an increased risk of affecting the human body. On the other hand, the presence of chlorine atoms is essential for the production of KrCl ^* (krypton chloride exciplex). Therefore, it has been necessary to limit the emission of ultraviolet light with a wavelength of 240 nm or more using an optical filter or the like. However, as the radiation amount of ultraviolet light with a wavelength of 240 nm or more increases, optical filters with higher precision are required.

In view of the above, the present invention provides an excimer lamp and an inactivation device suitable for inactivating bacteria and viruses existing in space while ensuring safety for humans and animals.

One aspect of the excimer lamp according to the present invention comprises a discharge vessel in which a rare gas and a halogen are enclosed as light emitting gases, and a pair of first and second electrodes for generating a dielectric barrier discharge inside the discharge vessel. wherein the noble gas is krypton (Kr), the halogen is chlorine (Cl), and the atomic partial pressure (Ph) of the halogen relative to the atomic partial pressure (Pr) of the noble gas is The partial pressure ratio (Ph/Pr) of is 0.05% or more and less than 1%, and the discharge vessel is positioned therein between the first electrode and the second electrode, and a discharge is formed and a non-discharge region communicating with the discharge forming region and in which no discharge is formed, the spatial volume of the entire interior of the discharge vessel is Va [mm ³ ], and the spatial volume of the discharge forming region is A spatial volume ratio (Vd/Va) of the discharge forming region is 70% or less, where Vd [mm ³ ].

In the excimer lamp according to the present invention, the ratio of the halogen atomic partial pressure (Ph) to the rare gas atomic partial pressure (Pr) enclosed in the discharge vessel is limited to less than 1%. As a result, the amount of chlorine atoms enclosed in the discharge vessel can be relatively reduced, and light emission between excited halogen atoms can be suppressed. Therefore, the radiation amount of ultraviolet light having a wavelength of 240 nm or longer can be reduced.

In addition, the spatial volume ratio (Vd/Va) of the discharge forming region is reduced to 70% or less while the halogen atom partial pressure (Ph) is relatively lowered.
This is based on the following considerations. (1) Halogen disappearance is affected by the size of the surface area of the discharge forming region (the inner surface area of the container in the region where the discharge is formed). (2) As the spatial volume of the non-discharge region increases, the space in which the halogen is not excited expands, and the halogen can be kept in the discharge vessel without being excited. In other words, it can be understood that a certain amount of halogen is retained in the discharge vessel without being extinguished. (3) By increasing the ratio of the spatial volume in which halogen is not excited, even when the ratio of the halogen atomic partial pressure to the rare gas atomic partial pressure (Pr) is limited to less than 1%, sufficient It becomes easy to maintain the amount of halogen, and loss of halogen can be suppressed.

As described above, by increasing the ratio of the non-discharge region, it becomes easier to secure the required amount of halogen in the discharge vessel even when the halogen atom partial pressure is relatively small. In addition, the following advantages are obtained by increasing the ratio of the non-discharge area.
Even if the halogen excited in the discharge formation region is injected into the discharge vessel and reduced from the discharge vessel, a sufficient non-discharge region in which the halogen is not excited is ensured, so that the halogen atomic partial pressure in the discharge vessel is reduced. difficult to change. This suppresses changes in the lighting characteristics due to changes in the halogen atom partial pressure, and also suppresses the effects of changes in illuminance due to changes in the partial pressure ratio between the rare gas partial pressure and the halogen atom partial pressure. lead to doing

Also, by reducing the halogen atom partial pressure in the discharge vessel to less than 1%, the startability of the excimer lamp can be enhanced.
Here, the halogen atom partial pressure is a partial pressure obtained by compensating the amount of halogen contained in the vapor phase halogen compound or halogen gas in terms of atoms. For example, when the number of halogen atoms (X) of a gas phase molecule (HX or A·HX) containing a halogen atom (H) is 1, the partial pressure of the sealed gas of the gas phase molecule is the halogen atom partial pressure. Further, when the number of halogen atoms (X) contained in the gas phase molecule is 2, the halogen atom partial pressure is obtained by doubling the gas partial pressure of the gas phase molecule.
Taking a chlorine atom as an example, if the gas phase molecule is hydrogen chloride (HCl), the partial pressure of the filled gas corresponds to the partial pressure of the halogen atom, and if it is chlorine gas (Cl ₂ ), the partial pressure of the filled gas is doubled. corresponds to the halogen atom partial pressure.
In addition, the rare gas atomic partial pressure here is a partial pressure obtained by compensating the gas phase rare gas amount in terms of atoms. For example, taking krypton as an example, a value obtained by doubling the filled gas partial pressure of krypton gas (Kr ₂ ) corresponds to the rare gas atomic partial pressure.

Further, the partial pressure ratio (Ph/Pr) of the atomic partial pressure (Ph) of the halogen to the atomic partial pressure (Pr) of the rare gas may be 0.5% or less.
By lowering the ratio of the halogen atom partial pressure to the rare gas atom partial pressure, the light emission between the excited halogen atoms can be further suppressed. Therefore, it is possible to further reduce the radiation amount of ultraviolet light having a wavelength of 240 nm or more.

Furthermore, the spatial volume ratio (Vd/Va) of the discharge forming region may be 50% or less. Thereby, the above effect can be made more conspicuous.

Moreover, in the above excimer lamp, it is preferable that the first electrode and the second electrode are arranged in contact with the outer surface of the discharge vessel.
The outer surface here refers to the outer surface of the discharge space in which the luminous gas is enclosed, and is the surface that does not come into contact with the luminous gas. If the electrodes are provided inside the discharge vessel (arc tube), the halogen in the luminous gas is likely to be absorbed. The absorption can be suppressed by arranging the electrodes outside the discharge vessel.

Further, the contact area between the discharge vessel and the first electrode and the second electrode may be 50% or less of the outer surface area of the discharge vessel.
Even if the electrodes are provided on the outer surface of the discharge vessel, the excited halogens tend to gather in the regions of the discharge vessel that are in contact with the electrodes and be implanted. By reducing the contact area between the discharge vessel and the electrode, it is possible to suppress the injection of halogen into the discharge vessel and suppress the consumption of halogen.

Further, one aspect of the inactivation device according to the present invention includes a discharge vessel in which a rare gas and a halogen are enclosed as luminescence gases, and a pair of first electrodes and a second electrode for generating a dielectric barrier discharge inside the discharge vessel. A deactivation device comprising an excimer lamp comprising two electrodes,
The rare gas is krypton (Kr), the halogen is chlorine (Cl), and the partial pressure ratio (Ph/Pr) of the atomic partial pressure (Ph) of the halogen to the atomic partial pressure (Pr) of the rare gas is , 0.05% or more and less than 1%, and the discharge vessel includes therein a discharge forming region located between the first electrode and the second electrode in which a discharge is formed; and a non-discharge region that communicates with the ^region and in which no ^discharge is formed. A spatial volume ratio (Vd/Va) of the discharge forming region is 70% or less.

The deactivation device according to the present invention limits the ratio of the halogen atomic partial pressure (Ph) to less than 1% with respect to the rare gas atomic partial pressure (Pr) enclosed in the discharge vessel. As a result, the amount of chlorine atoms enclosed in the discharge vessel can be relatively reduced, and light emission between excited halogen atoms can be suppressed. Therefore, the radiation amount of ultraviolet light having a wavelength of 240 nm or more can be reduced.

In addition, the spatial volume ratio (Vd/Va) of the discharge forming region is reduced to 70% or less while the halogen atom partial pressure (Ph) is relatively lowered. As a result, as described above, the ratio of the spatial volume in which halogen is not excited is ensured, and even when the ratio of the halogen atomic partial pressure to the rare gas atomic partial pressure (Pr) is limited to less than 1%, the discharge forming region It becomes easy to retain a sufficient amount of halogen, and loss of halogen can be suppressed.

According to one aspect of the present invention, it is possible to provide an improved excimer lamp in which a rare gas and a halogen are enclosed in the discharge vessel.

1 is an external image diagram of a light source device provided with an excimer lamp of this embodiment. FIG. It is a figure which shows typically the excimer lamp in this embodiment. FIG. 2 is a schematic diagram of the excimer lamp in the present embodiment as seen in the tube axis direction; It is a figure which shows the state inside the discharge container of the excimer lamp in this embodiment. FIG. 2 is an enlarged view of the main part of the emission spectrum of the KrCl excimer lamp; FIG. 4 is a diagram schematically showing another example of an excimer lamp; FIG. 4 is a schematic diagram of another example of an excimer lamp viewed in the tube axis direction; FIG. 4 is a schematic cross-sectional view of another example of an excimer lamp in the longitudinal direction; FIG. 9 is a schematic cross-sectional view in the width direction of the excimer lamp of FIG. 8 ; FIG. 3 is a schematic cross-sectional view of another example of an excimer lamp in the tube axis direction; 11 is a schematic cross-sectional view of the excimer lamp of FIG. 10 in the direction perpendicular to the axis; FIG. FIG. 4 is a schematic cross-sectional view of another example of an excimer lamp in the longitudinal direction; 13 is a schematic cross-sectional view of the excimer lamp of FIG. 12 in the width direction; FIG. FIG. 4 is a schematic diagram of another example of an excimer lamp viewed from the direction perpendicular to the axis; FIG. 15 is a schematic diagram of the excimer lamp of FIG. 14 as seen from the tube axis direction; FIG. 4 is a diagram showing the state inside the discharge forming region of the KrCl excimer lamp;

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is an external image diagram of a light source device (deactivation device) 100 including an excimer lamp according to this embodiment. 2 is a diagram schematically showing the excimer lamp in this embodiment, and FIG. 3 is a schematic diagram of the excimer lamp in this embodiment viewed in the tube axis direction.

As shown in FIG. 1 , the light source device 100 includes a housing 11 and an excimer lamp 12 arranged within the housing 11 .
The housing 11 is provided with an opening 11a that serves as a light exit window. A window member made of quartz glass, an optical filter for blocking unnecessary light, or the like can be provided in the opening 11a. A light extraction surface of the excimer lamp 12 is arranged to face the light exit window.
Although the light source device 100 includes a plurality of excimer lamps 12 in FIG. 1, the number of excimer lamps 12 is not particularly limited.

The excimer lamp 12 comprises a straight tubular discharge vessel 13 hermetically sealed at both ends. The discharge vessel 13 is made of quartz glass. In addition, the discharge vessel 13 is filled with a rare gas and a halogen gas as a light emission gas. In this embodiment, krypton (Kr) is used as the rare gas, and chlorine gas (Cl ₂ ) is used as the halogen gas.

A pair of electrodes (first electrode 14 and second electrode 15 ) are arranged in contact with the outer surface of the discharge vessel 13 . As shown in FIG. 2, the first electrode 14 and the second electrode 15 are arranged on the side surface of the discharge vessel 13 facing the light extraction surface (lower surface in FIG. 2) in the direction of the tube axis of the discharge vessel 13 (FIG. 2). left-right direction) are spaced apart from each other.
The discharge vessel 13 is arranged so as to straddle the two electrodes 14 and 15 while being in contact therewith. Specifically, grooves are formed in the two electrodes 14 and 15 as shown in FIG. Thereby, the discharge vessel 13 has a contact surface 13a with the electrodes 14, 15 as shown in FIG.

Of this pair of electrodes, one electrode (for example, the first electrode 14) is the high-voltage side electrode, and the other electrode (for example, the second electrode 15) is the low-voltage side electrode (ground electrode). By applying a high-frequency voltage between the first electrode 14 and the second electrode 15, excited dimers are generated in the internal space of the discharge vessel 13, and excimer light with a center wavelength of 222 nm is emitted from the light extraction surface of the excimer lamp 12. be radiated.

As shown in FIG. 2, inside the discharge vessel 13, the area between the pair of electrodes 14 and 15 becomes the discharge forming area A where the discharge is formed. A non-discharge area B communicating with the discharge formation area A is formed outside the discharge formation area A in the discharge vessel 13 in the tube axis direction.
The discharge formation area A is an area in the internal space of the discharge vessel 13 in which a discharge is formed and light is emitted when lit. electrodes) are arranged to face each other, the internal space region sandwiched between the electrodes arranged to face each other can be determined as the discharge forming region A.
In addition, when a pair of electrodes (the first electrode and the second electrode) are not arranged opposite to each other across the internal space, and are arranged at different positions in the direction in which the internal space expands, the position where the first electrode is arranged to the position where the second electrode is arranged can be determined as the discharge formation region A.
In addition, when a pair of electrodes (the first electrode and the second electrode) are arranged to face each other and the first electrode and the second electrode are arranged at different positions in the direction perpendicular to the facing direction, the facing arrangement A discharge forming area A can be determined as an internal space area sandwiched between the electrodes.

By the way, in an excimer lamp having a discharge vessel filled with a rare gas and halogen, a phenomenon occurs in which the halogen is driven into the quartz glass forming the discharge vessel. This phenomenon is a phenomenon in which the halogen excited by the discharge reacts with the quartz glass forming the discharge vessel and enters the quartz glass. If halogen decreases or disappears from the discharge forming region A inside the discharge vessel due to this phenomenon, the illuminance of the light emitted from the excimer lamp is lowered. In particular, excited chlorine atoms tend to enter quartz glass, and the illuminance tends to decrease when chlorine atoms are used as the luminous gas.

It is conceivable to increase the amount of halogen enclosed in anticipation of the disappearance of the halogen. When the ratio is large, the excited halogen atoms collide with each other to easily generate intrinsic light emission. Specifically, collisions between chlorine atoms tend to cause light emission in a wavelength band of 240 nm or more.
In addition, there is a risk that the ratio of the rare gas and the halogen will change from the proper ratio, resulting in large fluctuations in lighting characteristics (startability) and life characteristics. Specifically, if an attempt is made to increase the amount of halogen to be charged, the pressure of the halogen to be charged increases and the starting voltage increases, making it difficult to start the lamp or, in the worst case, failing to light it.

The present inventors have made intensive studies and found that in an excimer lamp using krypton (Kr) as a rare gas and chlorine (Cl) as a halogen, the partial pressure ratio of the atomic partial pressure (Ph) of the halogen to the atomic partial pressure (Pr) of the rare gas By limiting (Ph/Pr) to less than 1%, Cl ^* emission (emission with a peak wavelength of 257 nm, also referred to as chlorine emission) between chlorine atoms was suppressed. Furthermore, by setting the partial pressure ratio (Ph/Pr) of the atomic partial pressure (Ph) of the halogen to the atomic partial pressure (Pr) of the rare gas to 0.05% or more, KrCl ^* (krypton chloride exciplex) is generated. can be kept to a minimum.

In addition, a region (non ^- discharge region B) in which no discharge is formed is formed in the discharge vessel. When the volume is Vd [mm ³ ], the spatial volume ratio (Vd/Va) of the discharge forming region is 70% or less. As a result, the non-discharge area occupies 30% or more of the entire area, thereby suppressing consumption of halogen. Consideration of the spatial volume of the discharge vessel including the non-discharge area will be described in detail below.

As shown in FIG. 4, when a discharge is formed in the discharge forming region A, chlorine present in the discharge forming region A is excited, but chlorine present in the non-discharge region B where no discharge is formed is not excited. Therefore, even if the chlorine (Cl ^* ) excited in the discharge formation area A is driven into the discharge vessel 13 and disappears from the discharge vessel 13, the chlorine (Cl) contributing to light emission is sufficient in the non-discharge area B. , chlorine (Cl) is supplied from the non-discharge region B to the discharge formation region A.
As a result, even if chlorine disappears from the discharge vessel 13, by forming the non-discharge region B large, the partial pressure ratio between the rare gas and the halogen can be prevented from significantly varying, and the required amount for the discharge formation region A can be prevented. Halogen is easier to maintain for a long time. Specifically, the partial pressure ratio (P Cl /P _Kr ) of the atomic partial pressure (P _Cl ) _{of chlorine gas (Cl 2 ) to the atomic partial pressure (P Kr ) of} krypton gas (Kr ₂ ) is 0.05%. Even when the content is limited to less than 1%, the necessary amount of halogen for the discharge forming region A is likely to be maintained for a long period of time.

In this way, the non-discharge region B can function as a storehouse of chlorine atoms (Cl). Therefore, it is possible to increase the amount of halogen enclosed in the discharge vessel while maintaining a predetermined enclosed gas pressure (halogen atom partial pressure), thereby improving the light emission life.
Specifically, the spatial volume (Vd) of the discharge forming region A is set to 70% or less of the total spatial volume (Va) of the inside of the discharge vessel (including the discharge forming region A and the non-discharge region B). The ratio of the spatial volume (Vn) of the discharge region B is formed to be large.

Halogen gas or a halogen compound can be used as means for supplying halogen into the discharge vessel. Here, the halogen that contributes to the discharge is a gas, and the halogen is enclosed based on the value of the halogen atom partial pressure [kPa] in the discharge vessel. Examples of chlorine atoms include chlorine gas (Cl ₂ ) and hydrogen chloride (HCl).
Further, the halogen atom partial pressure in the present invention is the partial pressure value of the halogen atom, and corresponds to the partial pressure of the filled gas in the case of hydrogen chloride (HCl), and the partial pressure of the filled gas in the case of chlorine gas (Cl ₂ ). corresponds to twice the pressure. Similarly, the rare gas atomic partial pressure is the value of the partial pressure of the rare gas atoms, and in the case of krypton gas (Kr ₂ ), the value obtained by correcting the partial pressure of the sealed gas by two times corresponds to the rare gas atomic partial pressure. .

Further, when the ratio of the non-discharge area B to the internal space volume (Va) of the discharge vessel increases, the amount of halogen that can be stored in the non-discharge area B without being excited can be increased. Therefore, the spatial volume (Vd) of the discharge forming region A is 65% or less, further 60% or less of the spatial volume (Va) of the entire interior of the discharge vessel including the discharge forming region A and the non-discharge region B. , further to 55% or less, and further to 50% or less. For example, by intentionally setting a spatial volume equal to or greater than the spatial volume of the discharge forming region A to be the non-discharge region B, the partial pressure ratio (Ph/Pr) of halogen to the rare gas is limited to less than 1%. Even in this case, it becomes easier to supply the required amount of halogen to the discharge forming region A over a long period of time. The spatial volume (Vd) of the discharge forming region A and the spatial volume (Vn) of the non-discharge region B can be appropriately adjusted by the positions and contact surfaces of the first electrode and the second electrode provided in the discharge vessel. .

Further, by increasing the ratio of the non-discharge region B, even if the halogen atoms excited in the discharge formation region A are injected into the discharge vessel and the halogen atoms in the discharge vessel decrease, the halogen atoms in the discharge vessel It becomes difficult for the partial pressure to fluctuate. This is because the halogen atoms are not excited and are held in the non-discharge region B, which suppresses changes in the lighting characteristics due to fluctuations in the halogen atom partial pressure, and also suppresses the change in the rare gas partial pressure and the halogen partial pressure. This makes it difficult for the partial pressure ratio to fluctuate, prevents the generation of excited dimers from being inhibited, and suppresses the influence of a decrease in illuminance.

In general, an excimer lamp using discharge is designed so that a non-discharge area B, where no discharge is formed, is made as small as possible, and a discharge formation area A, where discharge is formed, is secured as large as possible.
On the other hand, in the present embodiment, by forming the non-discharge region B large as described above, good life characteristics can be obtained. By forming the non-discharge region B large, even when chlorine is consumed in the discharge formation region A, the partial pressure of chlorine atoms in the discharge vessel is less likely to fluctuate, in other words, chlorine is retained in the non-discharge region B. This is because it has the effect of reducing the effect of chlorine consumption in the discharge forming region A.

In the excimer lamp according to the present invention, a rare gas and a halogen are enclosed in a discharge vessel as light emitting gases. Specifically, krypton (Kr) as a rare gas and chlorine (Cl) as a halogen are enclosed.
Further, the partial pressure ratio (Ph/Pr) of the atomic partial pressure (Ph) of the halogen to the atomic partial pressure (Pr) of the rare gas is set to 0.05% or more and less than 1%, so that KrCl ^* (krypton chloride Chlorine luminescence (peak wavelength: 257 nm) between chlorine atoms is suppressed while generating an exciplex. In order to further suppress chlorine emission, the partial pressure ratio (Ph/Pr) of the atomic partial pressure (Ph) of the halogen to the atomic partial pressure (Pr) of the rare gas may be less than 0.9%. may be less than 0.8%, further less than 0.7%, and further less than 0.6%.
FIG. 5 is an enlarged view of the main part of the emission spectrum of the KrCl excimer lamp, showing the relationship between the intensity ratio and the emission wavelength (nm) when the peak wavelength (222 nm) is set to "1". A spectral irradiance meter (USR-45V/D) manufactured by Ushio Inc. was used to measure the emission spectrum. FIG. 5 shows the magnitude of chlorine light emission (▼) when the partial pressure ratio (Ph/Pr) of chlorine to krypton is 0.1%, 0.5%, 1%, and 1.5%. As can be seen from FIG. 5, as the partial pressure ratio of chlorine to krypton (Ph/Pr) becomes smaller, the chlorine emission (▴) can be reduced. That is, the partial pressure ratio (Ph/Pr) of chlorine to krypton is preferably less than 1%, more preferably less than 0.5%. Chlorine is essential for the production of KrCl ^* (krypton chloride exciplex), and the partial pressure ratio (Ph/Pr) of chlorine to krypton must be at least 0.05%.

[Measuring Means for Halogen Atom Partial Pressure]
The halogen atom partial pressure in the present invention is the partial pressure value of halogen atoms, and is calculated from the internal volume of the discharge vessel and the amount of halogen present in the discharge vessel.
As a method for measuring the amount of halogen, either ion chromatography or titration, or both can be used in combination, depending on the gas component. Specifically, an appropriate amount of liquid sample pieces are extracted from a liquid sample in which the emission gas component in the discharge vessel is dissolved in pure water, and the ion components contained in the liquid sample pieces are detected. When the ion chromatography method and the titration method are used together, a plurality of liquid sample pieces are extracted from the liquid sample, and the ion components contained in each liquid sample piece are analyzed by the ion chromatography method and the titration method, respectively. To detect.

[Measurement Means for Rare Gas Atomic Partial Pressure]
The rare gas atom partial pressure in the present invention is the partial pressure value of the rare gas atoms, and is calculated from the internal volume of the discharge vessel and the amount of rare gas present in the discharge vessel. Gas chromatography mass spectrometry can be used as a method for measuring the amount of rare gas. Specifically, it can be measured with a quadrupole mass spectrometer.

Furthermore, when the contact area between the discharge vessel and the electrode was confirmed, the smaller the contact area of the electrode, the more improved the luminous life. This is because excited chlorine (Cl ^* ) is likely to be injected into the bulb in the region in contact with the electrode. Therefore, when the electrodes are arranged on the outer surface of the discharge vessel, it is desirable to reduce the width of the electrodes.
For example, by setting the contact area between the discharge vessel and the first electrode and the second electrode to 50% or less of the outer surface area of the discharge vessel, consumption of halogen in the discharge vessel can be well suppressed. However, the smaller the electrode width, the more difficult it is to form discharge, so it is necessary to balance this with light emission characteristics. For example, the contact area (Se) between the discharge vessel and the first electrode and the second electrode has an area ratio (Se/Sd) to the inner surface area (Sd) of the discharge vessel in the discharge forming region A of 10% or more, Furthermore, it is desirable to be 20% or more, more preferably 30% or more. In the case of enlarging the discharge forming region, the contact area (Se) of the electrode is also increased, thereby facilitating the formation of the discharge.

2 and 3, when the pair of electrodes 14 and 15 are arranged on one side surface of the discharge vessel 13, the contact area 13a between the discharge vessel 13 and the electrodes 14 and 15 is It is possible to widen the discharge forming region A while suppressing it.

As described above, the excimer lamp 12 in this embodiment comprises a discharge vessel 13 in which a rare gas and a halogen are enclosed as light emission gases, and a pair of first electrode 14 and second electrode 15 for generating a dielectric barrier discharge. And prepare. Here, the excimer lamp 12 in this embodiment is a KrCl excimer lamp using krypton (Kr) as a rare gas and chlorine gas (Cl ₂ ) as a halogen gas, and emits light with a central wavelength of 222 nm.

The discharge vessel 13 has, in its internal space, a discharge forming region A located between the first electrode 14 and the second electrode 15 and communicating with the discharge forming region A, and a non-discharge region where no discharge is formed. a discharge region B; The spatial volume of the discharge forming region A is set to 70% or less of the spatial volume inside the discharge vessel 13 including the discharge forming region A and the non-discharge region B.

In this way, the discharge vessel 13 is intentionally formed with a large area in which no discharge is formed, and the discharge vessel 13 is filled with just enough chlorine atoms. As a result, the chlorine can be retained in the discharge vessel 13 without being excited, and the consumption of chlorine can be suppressed. In addition, even if the chlorine atoms excited in the discharge formation region A are injected into the discharge vessel 13 and disappear from the discharge vessel 13, sufficient chlorine atoms are retained in the discharge vessel 13 so that the rare gas can be generated. It is possible to prevent the partial pressure ratio with halogen from fluctuating significantly. Therefore, it is possible to appropriately suppress the decrease in illuminance and improve the light emission lifetime.
The spatial volume (Vd) of the discharge forming region A is preferably 60% or less of the spatial volume (Va) inside the discharge vessel 13, and more preferably 50% or less of the spatial volume (Va). more preferred. In this case, better life characteristics are obtained.

Furthermore, the contact area between the discharge vessel 13 and the first electrode 14 and the second electrode 15 can be 50% or less of the outer surface area of the discharge vessel 13 . In this case, the injection of chlorine into the discharge vessel 13 can be suppressed, and the consumption of chlorine can be suppressed.
As described above, in the present embodiment, an excimer lamp in which a rare gas and a halogen are sealed as a light emission gas in the discharge vessel can be used as a light source capable of further extending the light emission life.

(Modification)
In the above embodiment, as shown in FIGS. 2 and 3, the excimer lamp 12 in which a pair of electrodes (the first electrode 14 and the second electrode 15) are arranged on one side surface of the discharge vessel 13 has been described. However, the configuration of the excimer lamp is not limited to the above. For example, like an excimer lamp 12A shown in FIGS. 6 and 7, a pair of annular electrodes (first electrode 14A and second electrode 15A) are arranged at both ends of a long discharge vessel 13A. may In this case also, as shown in FIG. 6, a discharge forming region A is formed between the pair of electrodes 14A and 15A, and a non-discharge region B communicating with the discharge forming region A is formed outside the discharge forming region A. be.

The excimer lamp, like the excimer lamp 12B shown in FIGS. 8 and 9, has a first electrode 14B and a second electrode 15B on the first main surface 13b and the second main surface 13c of the flat discharge vessel 13B, respectively. may be arranged. In this case also, the area sandwiched by the pair of electrodes 14B and 15B becomes the discharge forming area A, and the non-discharge area B communicating with the discharge forming area A is formed outside the discharge forming area A. FIG. The non-discharge regions B are formed at both ends in the tube axis direction of the discharge vessel 13B as shown in FIG. 8 and at both ends in the width direction of the discharge vessel 13B as shown in FIG.

Furthermore, the excimer lamp may be configured to include a discharge vessel 13C having a double-tube structure, like the excimer lamp 12C shown in FIGS. Here, the discharge vessel 13C has a cylindrical outer tube and a cylindrical inner tube which is arranged coaxially with the outer tube inside the outer tube and has an inner diameter smaller than that of the outer tube. The outer tube and the inner tube are sealed in the horizontal direction of FIG. 12, and an annular internal space is formed between them. A mesh-like first electrode (outer electrode) 14C and a film-like second electrode (inner electrode) 15C are arranged on the outer surface 13d of the outer tube and the inner surface 13e of the inner tube, respectively. In this case also, the area sandwiched by the pair of electrodes 14C and 15C becomes the discharge forming area A, and the non-discharge area B communicating with the discharge forming area A is formed outside the discharge forming area A.
The first electrode (outer electrode) 14C may be a mesh electrode, or may be a printed electrode formed by coating in a predetermined pattern shape, and an electrode having openings through which ultraviolet light is transmitted is adopted. can. The second electrode (inner electrode) may be a mesh electrode, a printed electrode, or a plate-shaped electrode. can.

In the examples of FIGS. 10 and 11, the outer electrode 14C and the inner electrode 15C are each connected to a high frequency power source (not shown) via lead wires (not shown). In order to prevent electric leakage, it is desirable to use the outer electrode 14C as a ground electrode (low voltage side electrode) and the inner electrode 15C as a high voltage supply electrode.
Furthermore, the outer electrode 14C and the inner electrode 15C are arranged long along the longitudinal direction (tube axis direction) of the discharge vessel, and the inner electrode 15C is preferably formed shorter than the outer electrode 14C. Since the inner electrode 15C is a high-voltage supply electrode, atmospheric discharge is likely to occur between it and the discharge vessel. Therefore, the inner electrode 15C is formed to be short, and the range of the area (discharge forming area A) sandwiched between the pair of electrodes 14C and 15C is determined so that the non-discharge area B communicating with the discharge forming area has a desired ratio. The risk of occurrence of atmospheric discharge can be reduced while forming at .

12 and 13, the excimer lamp has a first electrode 14D and a second electrode 15D on the first main surface 13b and the second main surface 13c of the flat discharge vessel 13C, respectively. may be arranged. Here, the first electrode 14D is an electrode member formed in a pattern by printed electrodes, and the second electrode 15D is a plate-shaped electrode member formed in a wider area than the first electrode 14D. In this case also, the area sandwiched by the pair of electrodes 14D and 15D becomes the discharge forming area A, and the non-discharge area B communicating with the discharge forming area A is formed outside the discharge forming area A. FIG.

Also, the excimer lamp may have a structure in which a plurality of electrodes are arranged on the side surface of a long discharge vessel 13E, like an excimer lamp 12E shown in FIGS. Here, the first electrodes 14E having the same polarity are dispersed at a plurality of locations on one side surface of the discharge vessel 13E, and the second electrodes 15E are arranged on the other side surface of the discharge vessel 13E. They are positioned so that they do not face each other. In this case, the internal space region between the position where the first electrode 14E is arranged and the position where the second electrode 15E is arranged becomes the discharge forming region A, and the discharge forming region A communicates with the discharge forming region A outwardly. A non-discharge area B is formed.

Moreover, it is desirable that all of the excimer lamps 12 (12A to 12E) described above are accommodated within the housing 11. FIG. Specifically, the housing 11 is provided with an opening 11a serving as a light exit window, and the opening 11a is provided with a window member made of, for example, quartz glass, an optical filter for blocking unnecessary light, or the like. , thereby forming an enclosed space within the housing.
By accommodating the excimer lamp 12 in the closed space, even if ozone is generated by ultraviolet light emitted from the excimer lamp, it is effectively suppressed from leaking out of the housing 11. - 特許庁can be done. In this case, it is desirable that the entire discharge forming area and non-discharge area of the discharge vessel be housed in the housing 11 . This is because the non-discharge region communicates with the discharge formation region, and the ultraviolet light emitted from the discharge formation region propagates through the non-discharge region.
Further, when a plurality of excimer lamps 12 are provided, the housing 11 may accommodate all the excimer lamps in a single housing 11 . Alternatively, a plurality of housings 11 are provided, and individual

Furthermore, it is desirable that the inner surface of the housing 11 is formed with a reflective surface in order to further increase the utilization efficiency of the ultraviolet light. Specifically, by forming a reflecting surface that reflects ultraviolet light belonging to a wavelength band of 200 nm or more and less than 240 nm (more preferably 200 nm or more and 230 nm or less), the ultraviolet light emitted from the opening 11A serving as a light exit window is formed. It is possible to effectively increase the amount of ultraviolet light that is emitted. For example, the housing 11 is desirably made of a material having a reflectance of 50% or more at a wavelength of 200 nm or more and less than 240 nm, or the inner surface of the housing 11 has a reflectance of 30% at a wavelength of 200 nm or more and less than 240 nm. % or more, more preferably 50% or more.

Also, the discharge vessel may be fixed to the inner surface of the housing 11 . At this time, it is desirable to interpose an insulating member between the housing 11 and the discharge vessel. In particular, when the housing 11 or the inner surface of the housing 11 is made of a conductive material, it is desirable to interpose an insulating member between the housing and the discharge vessel. This is to avoid discharge between the electrode and the housing through the space in the discharge vessel.
The present invention secures a predetermined non-discharge area by reducing the spatial volume ratio of the spatial volume Vd of the discharge forming area to the spatial volume Va of the entire interior of the discharge vessel. At this time, if a discharge occurs between the electrode and the housing through the space in the discharge vessel as described above, there is a possibility that an unwanted discharge will be formed in the non-discharge area. Therefore, it is desirable to interpose an insulating member between the discharge vessel and the housing. As the insulating member, glass, resin, insulating adhesive, or the like can be adopted. For example, it is desirable that the discharge vessel is fixed to the housing 11 so that the portion where the non-discharge region is formed and the housing 11 are connected via an insulating member. The above configuration can be adopted in all embodiments.

Further, the end portion of the portion where the non-light-emitting region of the discharge vessel is formed may be arranged apart from the inner surface of the housing 11 so as not to come in contact with the inner surface. In particular, when the housing 11 and the inner surface of the housing 11 are made of a conductive material, this is to avoid discharge between the electrode and the housing through the space in the discharge vessel. , to avoid the formation of unwanted discharges in the non-discharge areas. This configuration can also be adopted in all embodiments.

DESCRIPTION OF SYMBOLS 100... Light source device 11... Housing 12... Excimer lamp 13... Discharge container 14... First electrode 15... Second electrode A... Discharge formation area B... Non-discharge area

Claims (6)

a discharge vessel filled with a rare gas and a halogen as a luminous gas;
An excimer lamp comprising a pair of first and second electrodes for generating a dielectric barrier discharge inside the discharge vessel,
the noble gas is krypton (Kr), the halogen is chlorine (Cl),
The partial pressure ratio (Ph/Pr) of the atomic partial pressure (Ph) of the halogen to the atomic partial pressure (Pr) of the rare gas is 0.05% or more and less than 1%,
The discharge vessel includes therein a discharge forming region in which a discharge is formed and located between the first electrode and the second electrode, and a non-discharge region communicating with the discharge forming region and in which no discharge is formed. and
When the spatial volume of the entire interior of the discharge vessel is Va [mm ³ ] and the spatial volume of the discharge formation region is Vd [mm ³ ], the spatial volume ratio (Vd/Va) of the discharge formation region is 70%. An excimer lamp characterized by: 2. The excimer lamp according to claim 1, wherein the partial pressure ratio (Ph/Pr) of the atomic partial pressure (Ph) of the halogen to the atomic partial pressure (Pr) of the rare gas is 0.5% or less. . An excimer lamp, wherein the space volume ratio (Vd/Va) of the discharge forming region is 50% or less. 4. The excimer lamp according to claim 1, wherein the first electrode and the second electrode are arranged in contact with the outer surface of the discharge vessel. 5. An excimer lamp according to claim 4, wherein the contact area between said discharge vessel and said first and second electrodes is 50% or less of the outer surface area of said discharge vessel. a discharge vessel filled with a rare gas and a halogen as a luminous gas;
A deactivation device comprising an excimer lamp comprising a pair of first and second electrodes for generating a dielectric barrier discharge inside the discharge vessel,
the noble gas is krypton (Kr), the halogen is chlorine (Cl),
The partial pressure ratio (Ph/Pr) of the atomic partial pressure (Ph) of the halogen to the atomic partial pressure (Pr) of the rare gas is 0.05 or more and less than 1,
The discharge vessel includes therein a discharge forming region in which a discharge is formed and located between the first electrode and the second electrode, and a non-discharge region communicating with the discharge forming region and in which no discharge is formed. and
When the spatial volume of the entire interior of the discharge vessel is Va [mm ³ ] and the spatial volume of the discharge formation region is Vd [mm ³ ], the spatial volume ratio (Vd/Va) of the discharge formation region is 70%. A deactivation device with an excimer lamp characterized by:

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