JP7106945B2 - Excimer lamp, light irradiation device, and ozone generator - Google Patents

Description

The present invention relates to an excimer lamp, a light irradiation device, and an ozone generator.

Conventionally, an ozone generator using an ultraviolet lamp is known. Mercury lamps and excimer lamps (eg, xenon excimer lamps) are known as ultraviolet lamps for generating ozone.

Ultraviolet lamps are placed, for example, in the middle of ducts and air passages, and are usually lit and used in environments with low illuminance. Therefore, reliable startability (darkness startability) is required even in the dark.

In Patent Document 1, a discharge space filled with a discharge gas that generates excimer molecules and a pair of electrodes for inducing discharge in the discharge gas are provided, and at least one of the electrodes and the discharge An excimer lamp is disclosed in which a dielectric is interposed between a discharge space and an ultraviolet ray is generated in the discharge space (see claim 1, etc.).

Patent Document 2 discloses an external electrode type rare gas discharge lamp in which a pair of electrodes are arranged on the outer surface of a glass tube filled with a rare gas, and a conductive material is arranged on a part of the inner surface of the glass tube, It is disclosed that the conductive substance is positioned inside the glass tube so as to connect the position where one electrode exists and the position where the other electrode exists (claim 1, paragraph [0017], etc.) reference).

JP 2016-126934 A JP 2008-034272 A

Patent Documents 1 and 2 attempt to improve startability by substantially shortening the distance between the two electrodes (between the high voltage side electrode and the low voltage side electrode). Therefore, a conductive material or the like is provided in the discharge path, that is, between the high-voltage side electrode and the low-voltage side electrode.

However, in the configurations of Patent Document 1 and Patent Document 2, there is a risk that the conductive material or the like blocks the light after lighting, reducing the illuminance. In addition, after lighting, the discharge may be biased in the vicinity of the conductive material, etc., and uneven illuminance may occur. In addition, after lighting, current continues to flow through the conductive material or the like until the light is turned off, which may increase power loss and reduce the efficiency of light conversion. In particular, these disadvantages are significant in excimer lamps with a relatively small power of about 1 to several watts.

The present invention has been made in view of the above-mentioned problems, and its object is to ensure startability in the dark while reducing the decrease in illuminance, uneven discharge, and power loss. To provide an excimer lamp.
Moreover, this invention is providing the light irradiation apparatus provided with the said excimer lamp.
Another object of the present invention is to provide an ozone generator equipped with the excimer lamp.

The present inventor has made extensive research on excimer lamps. As a result, when the starting support member is provided on the inner surface of the arc tube in a region outside the electrode on the high voltage side, it surprisingly reduces the decrease in illuminance, the uneven discharge, and the loss of power. The inventors have found that the startability in the dark is improved, and have completed the present invention.

That is, the excimer lamp according to the present invention is
a light-emitting tube containing a light-emitting gas;
a pair of electrodes provided on the outer surface of the arc tube;
and a starting assist member provided on the inner surface of the arc tube,
The starting assist member is provided at least in a region X outside the pair of electrodes,
A distance A between the electrode closer to the starting assist member and the starting assist member is shorter than a distance Y between the pair of electrodes.

As described above, conventionally, as a method of improving the startability of an excimer lamp, it has been considered to provide a conductive material or the like in the discharge path, that is, between the high-voltage side electrode and the low-voltage side electrode. . On the other hand, the present invention is an invention based on a concept that is completely different from the concept of the prior art. That is, the present invention has surprisingly found that the startability in the dark is improved when the starting aid member is provided on the inner surface of the arc tube outside the electrode on the high voltage side. It is an invention completed by Such an effect is also apparent from the description of the examples given later.

According to the excimer lamp of the present invention, if the electrode of the pair of electrodes which is closer to the starting assisting member is used as the electrode on the high voltage side, the startability in the dark is improved. Even if the electrode of the pair of electrodes farther from the starting assist member is used as the electrode on the high voltage side, the startability in the dark cannot be improved.

The inventor of the present invention speculates that the reason why the startability in the dark is better than when the start assist member is not provided is either one of the following (1) and (2). ing.
(1) Electrons tend to fly to the auxiliary starting member that is close to the electrode on the high voltage side. Discharge continues stably.
(2) If the inside of the arc tube is left in the dark, the number of electrons for starting discharge will decrease. By providing the starting assisting member near the electrode on the high voltage side, the starting assisting member is charged and electrons are easily emitted. Since electrons are more likely to fly out, discharge is more likely to occur.

Further, in an excimer lamp, light emitted from a portion between electrodes of an arc tube is normally used. According to the excimer lamp of the present invention, since the starting assist member is provided in the region X outside the pair of electrodes, the range in which emitted light is blocked can be reduced. As a result, a decrease in illuminance can be suppressed.

Further, in the region X, almost no discharge occurs after lighting. Therefore, it is possible to suppress the occurrence of uneven discharge in the region X after lighting. Further, in the region X, almost no discharge occurs after lighting, so that power loss after lighting can be reduced.

As described above, according to the excimer lamp of the present invention, if the electrode of the pair of electrodes, which is closer to the starting assist member, is used as the electrode on the high voltage side, the illuminance is reduced, the discharge is uneven, and the power consumption is reduced. It is possible to secure startability in the dark while reducing loss.

In the above configuration, the arc tube includes a cylindrical portion having a first end and a second end, and a first cylindrical portion continuously formed from the first end and having a diameter that decreases with distance from the first end. a diameter-reduced portion; and a second diameter-reduced portion formed continuously from the second end and having a diameter that decreases with increasing distance from the second end;
The pair of electrodes is composed of a first electrode and a second electrode,
The first electrode is provided on the outer peripheral surface of the first end,
It is preferable that the second electrode is provided on the outer peripheral surface of the second end.

According to the above configuration, the starting assisting member may be provided in the first diameter-reduced portion or the second diameter-reduced portion. Therefore, the starting assisting member can be easily provided in the first diameter-reduced portion or the second diameter-reduced portion.

In the above configuration, it is preferable that the starting assist member is formed so as not to overlap the region in which the electrodes are formed.

If the starting aid member is formed so as not to overlap with the region where the electrode is formed, the startability in the dark becomes better, as can be seen from the examples.

In the above configuration, the starting assist member is preferably made of carbon.

In the manufacturing process of the excimer lamp, after the starting assist member is provided on the inner surface of the arc tube, for example, heating for strain relief may be performed. Here, carbon has high thermal stability. Therefore, if the starting aid member is made of carbon, the evaporation of the starting aid member due to heating or the like can be suppressed, and the reliability of the excimer lamp can be enhanced.

Further, the light irradiation device according to the present invention is
comprising the excimer lamp,
The starting assist member is provided at least in a region X outside the high-voltage side electrode.

According to the above configuration, the excimer lamp is provided, and the starting assist member is provided at least in the region X outside the electrode on the high voltage side. It is possible to provide a light irradiation device that ensures startability in the dark while reducing loss.

Further, the ozone generator according to the present invention is
comprising the excimer lamp,
The starting assist member is provided at least in a region X outside the high-voltage side electrode.

According to the above configuration, the excimer lamp is provided, and the starting assist member is provided at least in the region X outside the electrode on the high voltage side. It is possible to provide an ozone generator that ensures startability in the dark while reducing loss.

According to the present invention, it is possible to provide an excimer lamp capable of ensuring startability in the dark while reducing illuminance drop, discharge bias, and power loss. Further, it is possible to provide a light irradiation device including the excimer lamp. Also, an ozone generator comprising the excimer lamp can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows typically the ozone generator which concerns on this embodiment. 2 is a front view of the ozone generator shown in FIG. 1 with the front half of the housing removed for explanation. FIG. (a) is a sectional view in the tube axis direction of an excimer lamp provided in the ozone generator shown in FIG. 1, (b) is a Z1-Z1 sectional view thereof, and (c) is a Z2-Z2 sectional view thereof. It is a diagram. 4 is a front view of an arc tube included in the excimer lamp shown in FIG. 3(a); FIG. It is a Laue plot for evaluating lighting delay. It is a Laue plot for evaluating lighting delay.

First, an ozone generator according to one embodiment of the present invention will be described below with reference to the drawings. Since the excimer lamp is provided in the ozone generator, the excimer lamp will be explained in the explanation of the ozone generator.

FIG. 1 is a perspective view schematically showing an ozone generator according to this embodiment. FIG. 2 is a front view of the ozone generator shown in FIG. 1, with the front half of the housing removed for explanation.

As shown in FIGS. 1 and 2 , the ozone generator 10 includes a housing 12 and an excimer lamp 20 .

FIG. 3(a) is a sectional view of an excimer lamp provided in the ozone generator shown in FIG. , and its Z2-Z2 sectional view. FIG. 4 is a front view of an arc tube included in the excimer lamp shown in FIG. 3(a).

The excimer lamp 20 has an arc tube 22 filled with a luminous gas, a first electrode 24 a , a second electrode 24 b , and a starting assist member 29 provided on the inner surface of the arc tube 22 .

The arc tube 22 has a cylindrical portion 30, a first reduced diameter portion 33a, and a second reduced diameter portion 33b (see FIG. 4).

The cylindrical portion 30 has a donut-shaped hollow cylindrical cross section, and has a first end portion 31a at one end (the left end in FIG. 4) and a second end portion 31b at the other end (the right end in FIG. 4). have

The first reduced diameter portion 33a is formed continuously from the first end portion 31a in a direction away from the first end portion 31a (left direction in FIG. 4). The diameter of the first reduced diameter portion 33a decreases with increasing distance from the first end portion 31a, and is closed by an end surface 34a.
The second reduced diameter portion 33b is formed continuously from the second end portion 31b in a direction away from the second end portion 31b (to the right in FIG. 4). The diameter of the second reduced-diameter portion 33b decreases with increasing distance from the second end portion 31b, and is closed by an end surface 34b.
The shape of the end faces 34a and 34b is not particularly limited as long as they are closed, and may be curved or flat. Also, there may be protrusions or the like that are generated when the lid is closed.

In this embodiment, the case where the excimer lamp 20 is an excimer lamp utilizing dielectric barrier discharge will be described. It is not limited to the use of barrier discharge.

The shape of the arc tube 22 is not limited as long as it is a tubular shape with a closed interior, but it is preferably a circular tube shape with both ends sealed as in the present embodiment.

Although the material of the arc tube 22 is not particularly limited, it is preferably a material that transmits ultraviolet rays, and examples thereof include quartz glass.

The luminous gas is not particularly limited as long as it can emit light having a wavelength capable of generating ozone by irradiating oxygen. As the emission gas, xenon (emission wavelength: 172 nm) can be used.

The first electrode 24a is provided on the outer peripheral surface of the first end portion 31a. The second electrode 24b is provided on the outer peripheral surface of the second end portion 31b. In this embodiment, the first electrode 24a is the electrode on the high voltage side, and the second electrode 24b is the electrode on the low voltage side. The voltage applied to the first electrode 24a (electrode on the high voltage side) may be either a positive high voltage or a negative high voltage.

Although the shapes of the first electrode 24a and the second electrode 24b are not particularly limited, they are preferably cylindrical as in the present embodiment. This is because, if it is cylindrical, dielectric barrier discharge can occur more favorably. Other examples of the shape of the first electrode 24a and the second electrode 24b include, for example, a C-shaped cross section and a coil shape.

From the viewpoint of startability, it is preferable that the area covered by the first electrode 24a and the second electrode 24b on the outer peripheral surface of the arc tube 22 is larger. Therefore, it is preferable to have a cylindrical shape as in this embodiment.

In this embodiment, the first electrode 24a does not extend over the first reduced diameter portion 33a. That is, the first electrode 24a is in contact only with the cylindrical portion 30 of the arc tube 22 and is not in contact with the first reduced diameter portion 33a. In addition, the second electrode 24b does not extend over the second reduced diameter portion 33b. That is, the second electrode 24b is in contact only with the cylindrical portion 30 of the arc tube 22 and is not in contact with the second reduced diameter portion 33b.

The material of the first electrode 24a and the second electrode 24b is not particularly limited, but from the viewpoint of oxidation resistance and thermal shock resistance at high temperatures, stainless steel and kanthal (iron-chromium alloy) are preferable.

The starting assist member 29 is provided in the region X outside the pair of electrodes (the first electrode 24a and the second electrode 24b). More specifically, the starting assisting member 29 is provided on the inner surface of the arc tube 22 so as to cover the end surface 34 from the position spaced apart by the distance A from the first electrode 24a.
In this specification, the distance A refers to the shortest distance from the outermost position of the electrode to the innermost position of the starting assist member.

The distance A is shorter than the distance Y between the pair of electrodes (the distance between the first electrode 24a and the second electrode 24b). Since the distance A is shorter than the distance Y, electrons tend to fly to the starting assist member 29 closer to the electrode on the high voltage side (first electrode 24a). ) and the starting assist member 29, the discharge continues stably between the pair of electrodes.
In this specification, the distance Y is from the position of one electrode closest to the other electrode to the position of the other electrode closest to the one electrode. In this embodiment, the distance Y is set from the position of the first electrode 24a closest to the second electrode 24b (the right end of the first electrode 24a in FIG. 3A) to the second electrode 24b closest to the first electrode 24a. It is the distance to the position (the left end of the second electrode 24b in FIG. 3A).

If the distance A is a positive value, it is preferably small. The smaller the distance A, the better the startability in the dark. This is clear from the examples described later. The inventor speculates that the reason for this is that electrons are more likely to fly from the first electrode 24a to the starting assisting member 29 as the starting assisting member 29 is closer to the electrode on the high voltage side (the first electrode 24a). there is

Further, when the distance A is a positive value, the starting assist member 29 is arranged at a position that does not block the light emitted from the arc tube 22 . As a result, a decrease in illuminance can be suppressed.

Further, when the distance A is a positive value, discharge hardly occurs in the region X after lighting. Therefore, it is possible to suppress the occurrence of uneven discharge in the region X after lighting. Further, in the region X, almost no discharge occurs after lighting, so that power loss after lighting can be reduced.

The distance A may be 0 (zero) as long as the starting assist member 29 is provided in at least a part of the region X outside the first electrode 24a. That is, the starting assist member 29 may be formed so as to overlap the region where the first electrode 24a is formed. Even in this case, compared to the case where the starting assist member 29 is not formed, the startability in the dark is better. The reason for this is that by providing the starting assisting member 29 so as to overlap the first electrode 24a, the starting assisting member 29 is charged and electrons are easily emitted. It is inferred that discharge is more likely to occur because electrons are more likely to fly out.

Further, the starting assist member 29 may be provided in a region inside the first electrode 24a as long as it is provided in at least a part of the region X outside the first electrode 24a. Even in this case, compared to the case where the starting assist member 29 is not formed, the startability in the dark is better. The reason for this is that by providing the starting assisting member 29 so as to overlap the first electrode 24a, the starting assisting member 29 is charged and electrons are easily emitted. It is inferred that discharge is more likely to occur because electrons are more likely to fly out.
However, if the starting assist member 29 is provided in the region inside the first electrode 24a, that portion blocks the light emitted from the arc tube 22. As shown in FIG. Therefore, when the starting assist member 29 is provided inside the first electrode 24a, it is preferable that the region is narrow to some extent. For example, when the starting assist member 29 is provided inside the first electrode 24a, when the length of the distance Y is 100%, the length is up to 10% (more preferably, up to 5%). If so, the starting assist member 29 may be provided in the area inside the first electrode 24a. Further, when the starting assist member 29 is provided inside the first electrode 24a, it may be provided inside the protection portion 14, which will be described later.

Examples of the material for the starting assist member 29 include conductive substances and electron-emissive substances. Examples of the conductive substance include carbon, platinum, gold, silver, nickel, ITO (Indium Tin Oxide), FTO (F-doped Tin Oxide), and the like. Examples of the electron-emissive material include magnesium oxide (MgO), lanthanum oxide (La ₂ O ₃ ), cerium oxide (CeO ₂ ), yttrium oxide (Y ₂ O ₃ ), zirconium oxide (ZrO ₂ ), and boride. Metal compounds such as lanthanum (LaB ₆ ) and the like are included. Among others, carbon is preferable as the material for the starting assist member 29 . Since carbon has high thermal stability, it is possible to suppress evaporation of the attached starting assist member 29 due to heating or the like, and the reliability of the excimer lamp 20 can be enhanced.

As an example of a method of sealing the luminous gas into the luminous tube 22, first, a hollow cylindrical tube having a doughnut-shaped cross section and open at both ends is prepared. One end of the tube is then closed by thermal fusion. This results in a reduced diameter portion. Next, the starting assist member 29 is formed in the portion to be the region X. As shown in FIG. Methods of forming the starting assist member 29 include a method of depositing the material of the starting assist member 29 and a method of coating. Next, the inside of the cylinder closed at one end is decompressed (preferably, evacuated), and a luminescent gas is introduced into the cylinder. After that, the other end of the tube is quickly closed by hot melting. As described above, the luminous gas can be enclosed in the luminous tube 22 .

According to the excimer lamp 20, the starting assist member 29 is provided in the region X outside the first electrode 24a. become good.

In the excimer lamp 20 , when a high AC voltage is applied between the electrodes 24 , a dielectric barrier discharge is induced in the space 28 within the arc tube 22 . Then, the luminous gas is excited by this to enter an excimer state, and when returning from the excimer state to the original state (ground state), it emits light with a spectrum peculiar to the excimer (excimer light emission).

The excimer lamp 20 does not have electrodes inside the arc tube, but only on the outer peripheral surface. Therefore, the excimer lamp 20 can be easily manufactured by providing the start-up assisting member 29 in the arc tube 22, enclosing the emission gas, and then providing the electrode 24 on the outer peripheral surface.
Further, the excimer lamp 20 does not have electrodes inside the arc tube, and does not require wiring for electrically connecting the inside and the outside of the arc tube. Therefore, there is no member penetrating the wall surface of the arc tube 22 . Therefore, high reliability of the excimer lamp 20 can be maintained.

As described above, the excimer lamp 20 has no electrodes inside the arc tube, but only on the outer peripheral surface. Therefore, the excimer lamp 20 is easy to manufacture in a small size. From the viewpoint of facilitating miniaturization, the overall length of the excimer lamp 20 in the tube axis direction is preferably 10 to 150 mm, more preferably 10 to 100 mm, and even more preferably 10 to 50 mm. Further, the distance between electrodes is preferably 3 to 130 mm, more preferably 3 to 80 mm, even more preferably 3 to 30 mm. The inter-electrode distance is the distance between the closest portions of the electrodes. In the case of a cylindrical shape, the outer diameter is preferably 3 to 20 mm, more preferably 3 to 15 mm, still more preferably 3 to 10 mm. The wall thickness of arc tube 22 is preferably 0.1 to 2 mm, more preferably 0.1 to 1 mm, still more preferably 0.1 to 0.5 mm.
Note that the dimensions of the excimer lamp 20 are not limited to the dimensions described above unless there is a particular need for miniaturization. However, if the distance between the electrodes is large, dielectric breakdown may not occur in the arc tube 22, so it is preferable to set each dimension in consideration of the applied voltage.

The housing 12 is U-shaped. The housing 12 includes a first protection portion 14a provided to cover one electrode 24 (first electrode 24a) and a second protection portion provided to cover the other electrode 24 (second electrode 24b). 14b. Further, the housing 12 has a connection portion 16 that connects the first protection portion 14a and the second protection portion 14b. In other words, the housing 12 has a U-shaped housing 12 in which the first protective portion 14a, the connecting portion 16, and the second protective portion 14b are integrally formed. Also, the first protection portion 14a and the second protection portion 14b are separated from each other.

In the ozone generator 10, the first electrode 24a is covered with the first protective portion 14a, the second electrode 24b is covered with the second protective portion 14b, and the first protective portion 14a and the second protective portion 14b are separated. , the first electrode 24a and the second electrode 24b are covered with the protective portion 14 (the first protective portion 14a and the second protective portion 14b), and the central portion of the arc tube 22 in the tube axial direction is exposed. With such a configuration, the electrodes (first electrode 24a, second electrode 24b) are connected to the protective portion 14 (first protective portion 14a, second protective portion 14b) without significantly blocking the light emitted from the arc tube 22. ) can be covered by This makes it possible to prevent deterioration of the electrodes due to ozone while maintaining a high ozone generation efficiency. In addition, it is possible to prevent water present in the usage environment from reaching the electrodes.

An opening 18 corresponding to the tube diameter of the arc tube 22 is formed in the protective portion 14 (the first protective portion 14a and the second protective portion 14b). Since the opening 18 corresponding to the tube diameter of the arc tube 22 is formed in the protective portion 14 , the arc tube 22 can be arranged in the opening 18 . In addition, since the opening 18 corresponds to the tube diameter of the arc tube 22, ozone generated outside the housing 12 can be prevented from entering the housing 12 as much as possible.

The arc tube 22 and the connecting portion 16 are separated from each other, and a ventilation region 32 is formed between the arc tube 22 and the connecting portion 16 . Since the light emitting tube 22 and the connecting portion 16 are separated from each other to form the ventilation region 32, the light emitted from the light emitting tube 22 can be efficiently applied to the oxygen from all directions of the light emitting tube 22, and the ozone can be generated. The amount generated can be increased. Further, since the light emitting tube 22 and the connecting portion 16 are separated from each other, deterioration of the connecting portion 16 due to the light emitted from the light emitting tube 22 can be prevented. That is, the light emitted from the arc tube 22 hits the oxygen in the ventilation region 32 and is weakened, so that deterioration of the connecting portion 16 can be prevented.

The distance between the arc tube 22 and the connection portion 16 is preferably 1 mm or more, more preferably 5 mm or more, and still more preferably 10 mm or more from the viewpoints of preventing deterioration of the connection portion 16 and increasing the amount of ozone generated. From the viewpoint of miniaturization of the ozone generator 10, the separation distance is preferably 30 mm or less, more preferably 25 mm or less, and even more preferably 20 mm or less. The distance between the arc tube and the connecting portion means the distance between the closest portions between the arc tube and the connecting portion.

As shown in FIG. 2, the housing 12 accommodates an electrical component 36 such as an inverter for supplying power to the excimer lamp. The electrical component 36 and the electrodes 24 of the excimer lamp 20 are electrically connected by wiring 38 . Since the electrical component 36 is housed inside the housing 12, it is possible to prevent the electrical component 36 from being affected by external noise. In addition, it is possible to prevent noise that may be emitted from the electrical equipment 36 from leaking to the outside. The inner surface of the housing 12 may be provided with a conventionally known electromagnetic wave shielding layer (for example, an electromagnetic wave shielding film or the like).

The ozone generator 10 has been described above.

In the above-described embodiment, the case where the protector is part of the housing has been described. That is, the case where the electrodes are covered with the protective portion that is part of the housing has been described. However, the protector in the present invention is not limited to the housing. For example, the protective portion may be formed by applying an adhesive to the electrode and curing the adhesive. That is, the protective portion may be a cured adhesive provided to cover the electrodes.

The application (installation location) of the ozone generator described above is not particularly limited, but since it can be made small, it can be suitably used in locations where installation space is limited. For example, it can be suitably used inside air conditioners, toilets with a deodorizing function, and the like.

In the above-described embodiments, the case where the excimer lamp emits light (ultraviolet rays) having a wavelength capable of generating ozone has been described. That is, the case where the excimer lamp is used in the ozone generator has been described. However, the light emitted from the excimer lamp in the present invention is not limited to this example. You may Alternatively, for example, visible light may be used. Specifically, for example, the inner surface of the arc tube may be coated with a phosphor that emits visible light when irradiated with ultraviolet rays. In these cases, if the electrode on the side where the starting assisting member is provided is set to the high voltage side, it can be used as a light irradiation device such as a lighting device.

Hereinafter, the present invention will be described in detail using examples, but the present invention is not limited to the following examples as long as the gist thereof is not exceeded.

<Fabrication of excimer lamp>
(Example 1)
First, one end of a quartz glass tube having a diameter of 10 mm was closed by heat melting to obtain a reduced diameter portion. Next, a carbon core for vapor deposition with a diameter of 0.5 mm was cut to 3 mm and placed in the glass tube with the reduced diameter portion facing downward. After that, the carbon core was heated with a high frequency. The high-frequency heating only heats the carbon, not the glass tube. The carbon thus evaporated and adhered to the cold glass inner surface. After that, a mixed gas of xenon and neon (Xe:Ne=3:7) was charged at 100 Torr, and the other end was closed by thermal melting. As described above, an arc tube having an overall length of 40 mm was obtained. Note that neon is a buffer gas that does not contribute to light emission.
Next, a pair of electrodes were evenly placed on the left and right so that the distance between the electrodes (distance Y (see FIG. 3A)) was 20 mm. As described above, an excimer lamp according to Example 1 was obtained. The width of the electrodes is 3 mm. As a result, the distance A between the electrode closer to the carbon and the carbon is
3 mm. Ten excimer lamps according to Example 1 were produced.

(Example 2)
An excimer lamp according to Example 2 was obtained in the same manner as in Example 1, except that the carbon core for vapor deposition was cut to 5 mm. As a result, the distance A between the electrode closer to the carbon and the carbon was 1 mm. Ten excimer lamps according to Example 2 were produced.

(Example 3)
An excimer lamp according to Example 3 was obtained in the same manner as in Example 1, except that the carbon core for vapor deposition was cut to 6 mm. As a result, the distance A between the electrode closer to the carbon and the carbon was 0 mm. The carbon film does not exist inside the electrode closer to the carbon. Ten excimer lamps according to Example 3 were produced.

(Example 4)
An excimer lamp according to Example 4 was obtained in the same manner as in Example 1, except that the carbon core for vapor deposition was cut to 8 mm. As a result, the distance A between the electrode closer to the carbon and the carbon was 0 mm. Furthermore, a carbon film of 2 mm was present inside the electrode closer to the carbon. Ten excimer lamps according to Example 4 were produced.

(Comparative example 1)
An excimer lamp according to Comparative Example 1 was obtained in the same manner as in Example 1, except that no vapor deposition film of carbon was formed. Ten excimer lamps according to Comparative Example 1 were produced.

<Measurement of start delay time>
For the excimer lamps (10 each) according to the example and the comparative example, the time from application of a high voltage to dielectric breakdown (start delay time) was measured. At this time, in Example 1-4, the electrode on the side where the deposited film was formed was set to the high voltage side. Specifically, first, it was left under bright light for 14 hours, then moved to darkness, and a high voltage was applied from a lighting power supply. As a lighting power supply, a flyback type inverter having an open-circuit voltage of +4 kV and a frequency of 20 kV was used. The results are shown in FIGS. 5 and 6. FIG.

5 and 6 are Laue plots for evaluating lighting delay. The horizontal axis indicates the lighting delay time, and the vertical axis indicates the number of excimer lamps whose lighting delay time is later than the lighting delay time indicated on the horizontal axis in terms of probability. FIG. 6 is a diagram in which the horizontal axis of FIG. 5 is changed.

As shown in FIG. 5, the excimer lamp according to Comparative Example 1, which does not have a carbon deposition film, is compared with the excimer lamps according to Examples 1 to 4, which have a carbon deposition film in the region outside the high-voltage side electrode. As a result, there was a tendency for many to have a long start delay time.

Further, as shown in FIG. 6, among the excimer lamps according to Examples 1 to 4, Example 2, Example 1, Example 3, and Example 4 were arranged in descending order of start delay time. From the comparison between Examples 1 and 2 and Examples 3 and 4, it was found that the distance A (see FIG. 3(a)) is preferably greater than zero. Further, from the comparison between Example 1 and Example 2, it was found that when the distance A is a positive value, the smaller the distance A, the better. Further, from the comparison between Example 3 and Example 4, it was found that it is preferable that the carbon film does not exist inside the electrode.

REFERENCE SIGNS LIST 10 Ozone generator 12 Housing 14 Protection unit (first protection unit 14a, second protection unit 14b)
REFERENCE SIGNS LIST 16 connecting part 18 opening 20 excimer lamp 22 arc tube 24 electrode (first electrode 24a, second electrode 24b)
28 Space 29 Starting Auxiliary Member 30 Cylindrical Part 31a First End 31b Second End 33a First Reduced Diameter Part 33b Second Reduced Diameter Part 34a, 34b End Face 32 Ventilation Region 36 Electrical Equipment 38 Wiring

Claims (6)

a light-emitting tube containing a light-emitting gas;
a pair of electrodes provided on the outer surface of the arc tube and spaced apart in the tube axis direction ;
and a starting assist member provided on the inner surface of the arc tube,
The starting assist member is provided at least in a region X outside the pair of electrodes,
An excimer lamp, wherein a distance A between the electrode closer to the starting assist member and the starting assist member in a tube axis direction is shorter than a distance Y between the pair of electrodes. The arc tube includes a cylindrical portion having a first end and a second end, and a first reduced diameter portion formed continuously from the first end and having a diameter that decreases with increasing distance from the first end. , a second reduced diameter portion formed continuously from the second end and having a diameter that decreases with increasing distance from the second end;
The pair of electrodes is composed of a first electrode and a second electrode,
The first electrode is provided on the outer peripheral surface of the first end,
2. The excimer lamp of claim 1, wherein the second electrode is provided on the outer peripheral surface of the second end. 3. An excimer lamp according to claim 1, wherein said starting assisting member is formed so as not to overlap a region in which electrodes are formed. The excimer lamp according to any one of claims 1 to 3, wherein the starting aid member is made of carbon. Equipped with the excimer lamp according to any one of claims 1 to 4,
The light irradiation device, wherein the starting assist member is provided at least in a region X outside the electrode on the high voltage side. Equipped with the excimer lamp according to any one of claims 1 to 4,
The ozonizer according to claim 1, wherein the start assisting member is provided at least in a region X outside the electrode on the high voltage side.

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