KR100850299B1 - Uv lamp and uv irradiation unit - Google Patents

Abstract

The present invention relates to an ultraviolet lamp having a discharge tube formed in a cylindrical shape, wherein the outer peripheral wall of the discharge tube is provided with a curved portion and a flat portion for transmitting ultraviolet rays at opposite positions, and the curved portion is provided on the inner side of the discharge tube. The surface is formed so as to be a concave surface.

Description

UV Lamp and UV Irradiation Device {UV LAMP AND UV IRRADIATION UNIT}

The present invention relates to an ultraviolet lamp and an ultraviolet irradiation device.

Excimer lamps having a double tube structure are known as ultraviolet lamps used for cleaning devices for cleaning glass substrates for liquid crystal panels and the like (Japanese Patent Laid-Open No. 2003-257375 and Japanese Patent Laid-Open No. 9 (1997) -97597). Publication).

Similarly, it is known to use a cylindrical discharge vessel as an ultraviolet lamp used for a cleaning apparatus or the like (see Japanese Patent Laid-Open No. 2003-197152).

Similarly, it is known to use a discharge box of a rectangular box type as an ultraviolet lamp used for a cleaning device or the like (see International Patent Application Publication No. WO2004 / 025175).

However, in the double tube structure described in Japanese Patent Laid-Open No. 2003-257375 and Japanese Patent Laid-Open No. 9-97597, the generated ultraviolet rays radiate radially in all directions from the lamp. Therefore, the ultraviolet-ray radiated | emitted in the opposite direction to the object (workpiece W) wash | cleaned by ultraviolet-ray is not used for washing | cleaning. In order to solve this problem, for example, as shown in Fig. 8, a reflecting plate 101 is provided behind the lamp 100 (opposite to the workpiece W side). Thus, the irradiation efficiency can be improved by guiding the light emitted backward to the work W side.

In addition, in order to prevent ultraviolet rays from being absorbed by the oxygen present around the lamp 100 and lowering the irradiation intensity, the airtight structure in which the space between the lamp 100 and the reflector 101 is sealed to seal nitrogen gas. It is necessary to employ the lamp house 103. In this case, it is necessary to provide the window part 102 for ultraviolet irradiation to the workpiece | work W side of the lamp house 103.

However, when the lamp house 103 is used in this way, there is a problem that the entire apparatus is enlarged and the cost is also high in structure. In addition, since the glass material sandwiched between the reflecting plate 101 and the window portion 102 deteriorates with time due to ultraviolet rays, maintenance of these members is required separately. As a result, there arises a problem that the maintenance cost increases.

In the example disclosed in Japanese Patent Laid-Open No. 2003-197152, which is a Japanese Patent Laid-Open Publication, a light reflector (reflecting light) is attached to a portion of the outer peripheral surface of the lamp body opposite to the light irradiation direction. By setting it as such a structure, the lamp house mentioned above becomes unnecessary.

However, ultraviolet light is absorbed by oxygen in the air. Therefore, in order to irradiate the workpiece W with strong ultraviolet rays, it is necessary to bring the lamp as close to the workpiece W as possible. By the way, in such an example, since the lamp shape is cylindrical, the distance from when the ultraviolet light is emitted from the lamp to the work W is large depending on which direction the ultraviolet light is emitted and from which position of the lamp. It was different. Therefore, no matter how close the lamp is to the workpiece W, some ultraviolet rays necessarily reach the workpiece W after passing through a long distance in the air. As a result, the rate at which the ultraviolet rays are absorbed by the oxygen increases, which causes a problem that the irradiation efficiency of the ultraviolet rays decreases.

In the example described in International Publication No. WO2004 / 025175 of the International Patent Application, the discharge vessel is a rectangular box. In this discharge vessel, a mesh electrode through which ultraviolet rays can pass is provided on the lower surface, and an electrode that reflects ultraviolet rays is provided on the upper surface. In this example, since the electrode which reflects an ultraviolet-ray is formed in the upper surface, the lamp house as mentioned above is unnecessary.

For convenience of description, a mesh electrode through which the ultraviolet ray can pass through the upper surface of the six surfaces of the discharge vessel of the rectangular parallelepiped shown in FIG. 4 of WO2004 / 025175 is provided. The surface on which 1c) is installed is called the lower surface. Moreover, the side with larger area among the remaining four surfaces is called the front and back surface. In addition, the direction toward an upper surface and the direction toward a lower surface from the center part of a discharge container are called a lateral direction, and the direction toward a lower surface.

In this example of WO2004 / 025175, since the discharge vessel is in a rectangular box shape, the surface (lower surface) on the work W side is flat. Therefore, when the lower surface of the lamp approaches the workpiece W, the lower surface is uniformly close to the workpiece W at any position of the lower surface. Therefore, compared with the case where the cylindrical lamp mentioned above is used, the irradiation efficiency of an ultraviolet-ray can be made high.

However, such a box-shaped lamp has a problem of being easily cracked as compared to a cylindrical lamp. In the discharge container of ultraviolet lamps, such as an excimer lamp, gas is generally sealed by the pressure lower than atmospheric pressure at the time of extinction. There is also an ultraviolet lamp in which the gas pressure in the discharge vessel at the time of lighting becomes higher than atmospheric pressure. Therefore, the discharge vessel at the time of extinguishing is subjected to the pressing force by the atmospheric pressure from the outside. In addition, depending on the lamp, an expansion force by internal gas may be applied when the lamp is turned on. In the case of the discharge vessel of the rectangular box type as described above, it is necessary to make a large area between the upper surface on which the electrode reflecting ultraviolet rays is installed and the lower surface on which the mesh type electrode is installed so as to transmit ultraviolet rays. Therefore, the compressive force by atmospheric pressure and the expansion force by internal gas become larger in these surfaces than other surfaces. As a result, a large force is applied to the part of a side surface by the big pressure applied to the upper surface and the lower surface. As a result, the discharge vessel tends to crack in the side surface.

This invention is made | formed in order to solve said problem, The objective is to provide the ultraviolet lamp and ultraviolet irradiation apparatus which can obtain sufficient irradiation efficiency with a simple structure, and a discharge container does not easily crack.

According to a first aspect of the present invention, there is provided an ultraviolet lamp having a discharge tube formed in a tubular shape, the outer peripheral wall of the discharge tube being provided with a curved portion and a flat portion for transmitting ultraviolet rays at positions facing each other, and the curved portion is formed of a discharge tube. The inner side surface is formed so as to be a concave surface (see Fig. 2).

In addition, in the present invention, for convenience of explanation, the upper direction of FIG. 2 is the upper direction of the discharge tube (that is, the direction in which the curved portion is located is the upper direction), and the lower direction of FIG. 2 is the lower direction of the discharge tube (that is, for ultraviolet transmission The direction in which the flat part is located is called downward). The left-right direction of FIG. 2 is called the lateral direction of a discharge tube. In addition, the direction perpendicular | vertical to the paper surface in FIG. 2 is called the longitudinal direction of a discharge tube.

According to the first invention, a flat portion for transmitting ultraviolet rays is provided on the outer circumferential wall of the discharge tube. When the flat portion approaches the work W, the flat portion is flat, so that any position of the flat portion is uniformly close to the work W. FIG. Therefore, the problem that "the part of ultraviolet rays touches the workpiece | work W after passing a long distance in the air" which arises in the case of the conventional example using a cylindrical discharge container is suppressed. As a result, compared with the case where a cylindrical lamp is used, irradiation efficiency of an ultraviolet-ray can be made high.

Further, according to the first invention, the effect that the discharge tube is not easily cracked can be obtained as compared with the conventional example using the rectangular box-shaped discharge container. In the discharge tube of the first aspect of the invention, the outer circumferential wall facing the flat portion for ultraviolet transmission is a curved portion whose inner side is a concave surface. Therefore, even if a pressure force by atmospheric pressure and an expansion force by internal gas are applied to this discharge tube, the force is not concentrated at one place but is dispersed. Therefore, the problem that a force concentrates on the side surface and the side surface tends to crack in the case of the rectangular parallelepiped discharge container shown in FIG. 4 of WO2004 / 025175 is suppressed in the present invention.

Needless to say, "flatness" in the "flat portion" of the first invention does not mean only a perfect plane. Even if the flat part is slightly nonuniform, it is clear that the effect of the present invention can be obtained if the flat part is sufficiently flat compared with the opposing concave part.

In addition, the curved part in 1st invention is not necessarily comprised only by a curved surface. For example, as shown in FIG. 9, the curved portion facing the UV transmitting flat portion 201 is wider than the two arc-shaped portions 203 and the UV transmitting flat portion 201 sandwiched therebetween. It may be a narrow flat portion 202. Even in such a case, it is clear that the effect by the first invention can be obtained. In such a case, the width of the flat portion 202 included in the curved portion is preferably 2/3 or less of the width of the flat portion 201 for ultraviolet transmission, more preferably 1/2 or less, and 1/3 or less. It is more preferable. When the width | variety of the flat part 202 is equal or more than the width | variety of the flat part 201 for ultraviolet transmission, it is not included in the 1st invention of this invention. In such a case, as in the case of using a rectangular box-shaped discharge container, a strong force is applied to both arc-shaped portions of the flat portion 202 by the pressing force caused by atmospheric pressure applied to two opposing flat portions. As a result, the arc part becomes easy to crack. Therefore, the effect that a discharge tube does not crack easily by the 1st invention in this invention cannot be acquired.

In addition, as shown in FIG. 10, the curved part in 1st invention may be comprised from the some flat part 204 narrow enough narrowly than the flat part 201 for ultraviolet transmission. Even in such a case, it is clear that the effect by the first invention can be obtained.

However, it is preferable that the curved surface part in 1st invention is comprised by the one curved surface which does not contain a flat part. By doing in this way, the intensity | strength of a discharge tube can be strengthened more.

Moreover, it is more preferable that the curved surface part in 1st invention is comprised by the circular arc-shaped one curved surface which does not contain a flat part. By doing in this way, the intensity | strength of a discharge tube can be made very strong.

2nd invention by this invention WHEREIN: The ultraviolet lamp in 1st invention WHEREIN: An ultraviolet reflecting member is provided in the curved part, The ultraviolet reflecting member ranges from one side part to the other side part of a discharge tube along a curved part. In the cross section of the ultraviolet lamp which is formed more broadly and is perpendicular to the longitudinal direction of the discharge tube, the tangent plane to the ultraviolet reflecting surface at the point of the part below the one side among the ultraviolet reflecting surfaces in the ultraviolet reflecting member. It is perpendicular | vertical to a plane, and the direction which goes to the inside of a discharge tube is lower than the direction which goes to one side from the other side.

Where the side part in 2nd invention corresponds is demonstrated in the cross section of the discharge tube in FIG. The inner surface of the discharge tube in the flat part 201 for ultraviolet transmission formed in the outer wall surface of a discharge tube is made into a base. In the curved part 205 formed in the outer wall surface of a discharge tube, the point which is furthest from a base side among the inner surface of a discharge tube is made into the stationary point T. FIG. Through this stationary point T, a straight line orthogonal to the base is taken as a reference line. The intersection point of this baseline and the base is made into the low point B. Through a center point between the top point T and the bottom point B, a straight line perpendicular to the reference line is taken as the center line. At this time, the two intersections of the outer surface of the discharge tube and the center line in the curved portion 205 are side portions S1 and S2. Although the above description is a description in the cross section as shown in FIG. 11, since the discharge tube actually has a length in a direction perpendicular to the surface of FIG. 11, these side portions are lines extending in the longitudinal direction of the discharge tube. In addition, about the definition of this side part, it is the same also in invention except 2nd invention.

In the second invention, the "ultraviolet ray reflecting member is formed wider than the range from one side portion to the other side portion of the discharge tube along the curved portion" from one side portion S1 to the other side portion S2 along the curved portion 205. In the over-range, it means that at least the ultraviolet reflecting member 206 is present, and at least one of the two sides extends the ultraviolet reflecting member 206 beyond the side and to the downward direction.

12 is a cross-sectional view of the discharge tube in the case of a comparative example in which the discharge tube is cylindrical. As shown in FIG. 12, in the case of the cylindrical discharge tube 207, in order to suppress emission of the ultraviolet-ray from the side direction of a discharge tube, like the 2nd invention by this invention, the ultraviolet-ray reflection member 206 below side S1. ) Shall be extended. In this case, the direction from the point A of the ultraviolet reflecting member below the side portion S1 to the contact plane to the reflecting surface of the ultraviolet reflecting member and perpendicular to the inside of the discharge tube (in Fig. 12, the direction of the arrow pointing from the point A into the discharge tube). Silver becomes upward from the direction toward the side S2 from the side S1. That is, the ultraviolet-ray reflected by the ultraviolet-ray reflective member 206 lower than this side part S1 becomes strong in the upward direction rather than the downward direction. Therefore, in a part of ultraviolet rays, the number of times reflected in the discharge tube increases until it is emitted from the discharge tube toward the work W. In this way, when the number of reflections increases, ultraviolet rays are attenuated. As a result, there arises a problem that the amount of ultraviolet rays irradiated to the work W is reduced.

This also applies to the case of having a rectangular box discharge container. In the rectangular box-shaped discharge vessel, in order to suppress leakage of ultraviolet rays in the lateral direction, the ultraviolet reflecting members are provided on two side surfaces. In this case, a part of ultraviolet rays reciprocate several times by reflection between two side surfaces which mutually face each other. Ultraviolet rays attenuate before being emitted towards workpiece W. Therefore, even when a rectangular box-shaped discharge container is used, there is a problem that the emitted ultraviolet light intensity is weakened.

In 2nd invention by this invention, as shown in FIG. 11, in the point A of the part below one side S1, it is perpendicular | vertical to the contact plane to an ultraviolet-ray reflection surface, and is directed to the inside of a discharge tube (FIG. 11). Direction from the point A to the inside of the discharge tube) is lower than the direction from one side S1 to the other side S2. That is, the ultraviolet-ray reflected by the ultraviolet-ray reflecting member 206 below this side part S1 becomes stronger than it tends to advance upward. Therefore, the number of times reflected in the discharge tube is reduced until the ultraviolet rays are emitted from the discharge tube toward the work W. If the number of reflections can be reduced in this manner, the attenuation of the ultraviolet rays can be suppressed. As a result, the reduction of the amount of ultraviolet rays irradiated to the work W can be suppressed.

In the second invention, the "ultraviolet ray reflecting member is formed wider than the range from one side portion to the other side portion of the discharge tube along the curved portion" from one side portion S1 to the other side portion S2 along the curved portion 205. It does not mean that the ultraviolet reflecting member 206 must exist in the whole range. For example, a part of the range from one side S1 to the other side S2 has a light transmission window for ultraviolet intensity measurement, so the ultraviolet reflection member 206 does not need to be provided at the portion of the light transmission window. Even in such a case, it is evident that the effect of the second aspect of the invention can be obtained if the ultraviolet reflecting member 206 is provided in almost the entire range from one side S1 to the other side S2.

In 2nd invention, it is perpendicular | vertical to the tangent plane to a ultraviolet reflecting surface in all the points of a part below one side among the ultraviolet reflecting surfaces in an ultraviolet reflecting member, and the direction which goes to the inside of a discharge tube differs from one side part. It does not have to be downward than the direction toward the side. Even if there were some points which did not satisfy such conditions, it is clear that the effects of the second invention can be obtained if the above conditions were satisfied in most of the portions below the one side.

In FIG. 11, although the ultraviolet reflecting member 206 is formed in the outer surface of a discharge tube, although the 2nd invention by this invention is not limited to such a case, even if the ultraviolet reflecting member 206 is formed in the inner surface of a discharge tube. do.

According to a third aspect of the present invention, in the ultraviolet lamp according to the first aspect, an ultraviolet reflecting member is provided on a curved portion, and the ultraviolet reflecting member extends from one side portion to the other side portion of the discharge tube along the curved portion. It is formed more widely, and an ultraviolet-ray reflection member is a 1st electrode for producing the electrical discharge for ultraviolet-ray generation, It is characterized by the above-mentioned.

For example, when aluminum etc. are fixed to the outer wall surface of the curved part 205, and a 1st electrode is formed, this 1st electrode can also be used as the ultraviolet reflection member 206. As shown in FIG. If the first electrode has a function as an ultraviolet reflecting member, it is not necessary to provide the ultraviolet reflecting member 206 separately from the first electrode. As a result, since a manufacturing process and material cost can be reduced, a lamp can be made cheap.

In the lamp of a comparative example using a rectangular box discharge container, in order to suppress the emission of ultraviolet rays from the lateral direction of the discharge container, a first electrode having a function as an ultraviolet reflecting member is provided from both the upper surface of the discharge container to both sides. It shall be installed. In this case, it is difficult to provide the second electrode forming the discharge with the first electrode in a practical shape and so that the distance from the first electrode is uniform with any part of the first electrode. As a result, the distance between the first electrode and the second electrode is different depending on the portion of the first electrode. Therefore, the discharge is concentrated where the distance between the electrodes is short among the first electrode and the second electrode. As a result, there arises a problem that the discharge intensity is weakened.

In contrast, in the third invention according to the present invention, the first electrode is provided for causing a discharging for generating ultraviolet rays in the curved portion. Accordingly, the distance between the first electrode and the second electrode is substantially uniform even when the first electrode having a function as an ultraviolet reflecting member is provided in the lateral direction, which is different from the case of the comparative example using the rectangular box-shaped discharge container. It is possible to easily design one lamp (see, for example, FIG. 2).

In FIG. 2, although the 1st electrode is formed in the outer surface of a discharge tube, the 3rd invention by this invention is not limited to such a case, The 1st electrode may be formed in the inner surface of a discharge tube.

The 4th invention by this invention is the ultraviolet lamp in 1st invention WHEREIN: The material of a discharge tube is characterized by quartz glass.

In the lamp of the comparative example using the rectangular box discharge container, the amount of ultraviolet irradiation which touches the corner between a lower surface and a side surface among the inner surface of a discharge container is small compared with the surrounding part. It is understood that quartz glass causes a change in molecular structure upon receiving ultraviolet rays, and the degree of the change is considered to be proportional to the amount of ultraviolet irradiation. Therefore, when quartz glass is used for the material of a discharge tube, a nonuniformity arises in the grade of molecular structure change in a corner and its surroundings. As a result, there is a problem that damage occurs in the discharge vessel, and it is easy to crack.

In the 4th invention by this invention, in the outer peripheral wall of a discharge tube, the curved surface part in which the surface of the inner side of a discharge tube becomes a recessed surface is provided in the position which opposes the flat part for ultraviolet transmission. By making a discharge tube into such a shape, the amount of ultraviolet rays which reach | attain the corner part of both ends of a flat part among the inner surfaces of a discharge tube can be made so that it does not differ so much compared with the surrounding part. As a result, since the damage of the quartz glass by ultraviolet irradiation does not produce easily, a discharge tube does not crack easily.

According to a fifth aspect of the present invention, in the ultraviolet lamp of the third aspect, the first electrode is for earth connection, the first electrode is provided on the outer surface of the curved portion, and the second electrode for high voltage connection is inside the discharge tube. It is characterized by being installed.

In a lamp using a conventional rectangular box-type discharge container, two electrodes which induce discharge are both the outer side of the discharge container for the purpose of ease of manufacture and suppression of deterioration of the electrode due to the use of the lamp. Was installed on. When the lamp is turned on, a discharge occurs between one electrode (earth electrode) connected to the earth and the electrode (high voltage electrode) to which high voltage alternating current is applied. At this time, when the high voltage electrode is used on the lower surface for ultraviolet transmission, the high voltage electrode and the work W are close to each other, and according to the kind of the work W, there is a problem that a discharge occurs between the high voltage electrode and the work W. Therefore, it was necessary to use an earth electrode for the lower surface for ultraviolet transmission, and to use a high voltage electrode for the upper surface. In the lamp of a comparative example using such a rectangular box discharge container, in order to suppress the emission of ultraviolet rays from the lateral direction of the discharge container, a high voltage electrode having a function as an ultraviolet reflection member from both the upper surface of the discharge container to both sides. Assume that you have installed. In this case, the portion of the high voltage electrode on the side of the discharge vessel is close to the work W. As a result, there was a problem that a discharge easily occurred between the high voltage electrode and the work W, depending on the kind of the work W.

In 5th invention by this invention, a 1st electrode is provided in the outer surface of the curved part of a discharge tube. Therefore, it is easy to manufacture a 1st electrode and can suppress deterioration of a 1st electrode by use of a lamp. Moreover, in 5th invention, a 1st electrode is for earth connection. Therefore, although the first electrode is provided on the outer surface of the curved portion of the discharge tube, discharge from the first electrode to the work W does not occur. Moreover, in the 5th invention, since the 2nd electrode for high voltage connection is provided in the inside of a discharge tube, discharge from the 2nd electrode to the workpiece | work W is also suppressed.

In the case where a conventional cylindrical discharge tube is used, the first electrode is provided on the outer surface of the curved portion of the discharge tube for high voltage connection. In this case, since the discharge tube is cylindrical, the first electrode does not approach the vicinity of the work W. Therefore, in the case of the cylindrical discharge tube, even when the first electrode is provided on the outer surface of the curved portion of the discharge tube for high voltage connection, the discharge between the first electrode and the work W is not a problem. Therefore, 5th invention by this invention solves the problem peculiar when a discharge tube has the flat part for ultraviolet permeation | transmission.

According to a sixth invention of the present invention, in the ultraviolet lamp of the first invention, a first electrode is provided on a curved portion, and the first electrode is wider than a range from one side portion to the other side portion of the discharge tube along the curved portion. It is formed, and inside the discharge tube, a linear second electrode extending in the length direction of the discharge tube is provided, the second electrode is provided in the vicinity of the central portion of the flat portion, the first electrode and the second It is characterized in that the electrical discharge is generated between the electrodes.

The meaning of "near the center part of the flat part" in 6th invention is demonstrated in the cross section of the discharge tube in FIG. The inner surface of the discharge tube in the flat part 201 for ultraviolet transmission formed in the outer wall surface of a discharge tube is made into a base. At this time, the straight line WL is the one whose length of the portion entering the discharge tube is the longest among the straight lines parallel to the base. Two intersections between the straight line WL and the inner surface of the discharge tube are referred to as W1 and W2. In addition, let WC be the center point of this W1 and W2. At this time, among the points on the straight line WL, two points whose distance from WC is 1/4 of the distance between WC and W1 are defined as W3 and W4. At this time, the "near the center part of the flat part" is limited between the straight line perpendicular to the straight line WL through W3, and the straight line perpendicular to the straight line WL through W4. Moreover, the point which is furthest from the base among the surface inside the discharge tube in the curved part 205 formed in the outer wall surface of the discharge tube is made into the stationary point T. FIG. Through this stationary point T, a straight line orthogonal to the base is taken as a reference line. The intersection point of this baseline and the base is made into the low point B. The straight line HC passes through the top point T and the bottom point B center point among the straight lines parallel to the base. At this time, "the vicinity of the center part of the flat part" is limited between the straight line HC and a base. That is, the "near the center part of the flat part" in 6th invention becomes the inside of the four corner | corners in the discharge tube of FIG.

In the sixth invention, "the second electrode is provided near the center of the flat portion" means that the center point of the cross section perpendicular to the longitudinal direction of the discharge tube of the second electrode is "near the center of the flat portion". It means that it is installed.

According to the sixth invention, a linear one is used as the second electrode. Therefore, it is not necessary to use the mesh type electrode which is used for the ultraviolet permeable surface of the discharge container of the conventional rectangular box type ultraviolet lamp as a 2nd electrode. As a result, the amount of ultraviolet rays blocked by the second electrode can be reduced. According to the sixth invention, the first electrode is provided along the curved portion 205 formed so that the inner surface of the discharge tube is a concave surface, and the second electrode is located near the center of the flat portion 201. It is installed. The combination of these two electrodes makes the distance with the second electrode substantially uniform over a wide range of the first electrode. As a result, since discharge occurs in a wide range in a discharge tube, the effect that an ultraviolet intensity becomes strong can be acquired.

According to a seventh aspect of the present invention, in the ultraviolet lamp of the sixth aspect, the first electrode has a substantially arcuate cross section, and is disposed at an equidistant position from each point on the cross section of the first electrode in the longitudinal direction of the discharge tube. It is characterized in that the linear second electrode extending.

"Equivalent distance" in the seventh invention does not mean only the case where the distances are the same. Even if the distance is slightly different, it is considered to be "equal distance" when the difference is substantially the extent to which the discharge is generated from substantially all of the first electrodes.

According to the seventh aspect of the invention, since the discharge can be generated from substantially the entirety of the first electrode, the discharge occurs in a wider range in the discharge tube. As a result, the effect that an ultraviolet intensity becomes stronger can be acquired.

In the 8th invention by this invention, in the ultraviolet lamp of 1st invention, the 1st electrode is provided in the curved part, The linear 2nd electrode extended in the longitudinal direction of a discharge tube is provided in the inside of a discharge tube, And a discharge electrode is generated between the first electrode and the second electrode, an auxiliary electrode is provided in the flat portion, and an auxiliary discharge is generated between the second electrode and the auxiliary electrode. (See Figure 4).

Here, the auxiliary electrode easily causes discharge (main discharge) between the first electrode and the second electrode, and at the same time, serves to stabilize the discharging.

That is, first, a discharge (auxiliary discharge) occurs between the second electrode and the auxiliary electrode. Charged particles generated by this discharge, atoms or ions in a metastable state, and photons reduce the applied voltage required for generating and maintaining a discharging electric charge. As a result, it becomes possible to lower the voltage at the start of the lamp and to stabilize the discharge plasma at the time of lighting.

Moreover, in this kind of lamp, since there is high output, there exists a desire to raise sealing gas pressure. However, in this way, discharge becomes unstable in general (increasing the sealing gas pressure has the same effect as increasing the distance between electrodes under a constant applied voltage). However, in the eighth invention, since charged particles generated by auxiliary discharge, atoms or ions in a metastable state, and photons can be efficiently supplied to the kitchen space uniformly, ionization of the discharge gas existing in the kitchen space. ) Can increase the coefficient. As a result, the discharging space is in a state where the discharge is likely to occur, and thus the stability of the discharge can be ensured without increasing the applied voltage.

In the eighth aspect of the invention, auxiliary discharge is performed between the second electrode provided inside the discharge tube and the auxiliary electrode provided in the flat portion, and the kitchen transition is performed between the second electrode provided inside the discharge tube and the first electrode provided in the curved portion. Is done. With such a configuration, it is possible to efficiently induce the electrical discharge by the auxiliary discharge, and to secure a large electrical discharge area in the discharge tube.

In the ninth invention according to the present invention, in the ultraviolet lamp of the first invention, a first electrode is provided on a curved portion, and a linear second electrode extending in the longitudinal direction of the discharge tube is provided inside the discharge tube. The second electrode is provided in the vicinity of the central portion of the flat portion, and is configured such that electric discharge occurs between the first electrode and the second electrode, and no electrode other than the second electrode is provided in the flat portion. It is characterized by.

The meaning of "the 2nd electrode is provided in the vicinity of the center part of a flat part" in 9th invention is the same as the case in 6th invention.

In the ninth invention, "the electrodes other than the second electrode are not provided in the flat portion" does not mean that the second electrode is necessarily provided in the flat portion. The 2nd electrode may be provided in the flat part, and may be provided in the discharge tube spaced apart from the flat part.

According to the ninth invention, a linear one extending in the longitudinal direction of the discharge tube is used as the second electrode used for kitchen. As a result, the amount of ultraviolet rays blocked by the second electrode can be reduced. In addition, since electrodes other than the second electrode are not provided in the flat portion, a lamp having a small amount of ultraviolet rays blocked by the electrodes can be obtained. According to the ninth invention, the first electrode is provided along the curved portion 205 formed so that the inner surface of the discharge tube is a concave surface, and the second electrode is located near the center of the flat portion 201. It is installed. The combination of these two electrodes makes the distance with the second electrode substantially uniform over a wide range of the first electrode. As a result, since discharge occurs in a wide range in a discharge tube, the effect that an ultraviolet intensity becomes strong can be acquired.

10th invention by this invention is the ultraviolet lamp of 1st invention WHEREIN: The 1st electrode is provided in the curved part, The linear 2nd electrode extended in the longitudinal direction of a discharge tube is provided in the outer side of a discharge tube, The second electrode is provided in the vicinity of the central portion of the flat portion, and is configured such that electric discharge occurs between the first electrode and the second electrode, and no electrode other than the second electrode is provided in the flat portion. It is characterized in that (see Figure 3).

The meaning of "near the center part of the flat part" in 10th invention is demonstrated in the cross section of the discharge tube in FIG. The inner surface of the discharge tube in the flat part 201 for ultraviolet transmission formed in the outer wall surface of a discharge tube is made into a base. At this time, the straight line WL is the one whose length of the portion entering the discharge tube is the longest among the straight lines parallel to the base. Two intersections between the straight line WL and the inner surface of the discharge tube are referred to as W1 and W2. In addition, let WC be the center point of this W1 and W2. At this time, among the points on the straight line WL, two points whose distance from WC is 1/4 of the distance between WC and W1 are defined as W3 and W4. At this time, "near the center part of the flat part" means the part of the outer surface of the discharge tube in the flat part 201 between the straight line perpendicular to the straight line WL through W3, and the straight line perpendicular to the straight line WL through W4. It is considerable. That is, the "near the center part of the flat part" in 10th invention becomes a part recorded with the thick line among the outer surfaces of the flat part 201 of FIG.

In the tenth invention, "the second electrode is provided near the center of the flat portion" means that the center point of the cross section perpendicular to the longitudinal direction of the discharge tube of the second electrode is "near the center of the flat portion". It means that it is installed.

According to the tenth invention, a linear one extending in the longitudinal direction of the discharge tube is used as the second electrode used for kitchen. As a result, the amount of ultraviolet rays blocked by the second electrode can be reduced. Moreover, since electrodes other than a 2nd electrode are not provided in the flat part, the lamp with a small amount of ultraviolet rays interrupted | blocked by an electrode can be obtained. According to the tenth invention, the first electrode is provided along the curved portion 205 formed such that the inner surface of the discharge tube is a concave surface, and the second electrode is located near the center of the flat portion 201. It is installed. The combination of these two electrodes makes the distance with the second electrode substantially uniform over a wide range of the first electrode. As a result, since discharge occurs in a wide range in a discharge tube, the effect that an ultraviolet intensity becomes strong can be acquired.

In the 11th invention by this invention, in the ultraviolet lamp of 1st invention, a 1st electrode is provided in the outer surface of a curved part, and the 1st electrode is located in the vicinity of the boundary of a flat part and a curved part among the outer surfaces of a curved part. It is characterized by not being provided (for example, see FIG. 3).

According to the eleventh invention, since the first electrode is not provided in the vicinity of the boundary between the flat portion and the curved portion, the distance between the first electrode and the work W is increased. Therefore, even when the first electrode is used for the high voltage connection electrode, the effect that discharge does not easily occur between the first electrode and the work W can be obtained.

According to a twelfth invention of the present invention, in the ultraviolet lamp of the eighth invention, the auxiliary electrode is provided over the entire length of the discharge tube in the longitudinal direction.

As the discharge tube for the ultraviolet irradiation device, one long in the longitudinal direction is usually used. It is assumed that an auxiliary electrode is provided only at the end of the long discharge tube in the longitudinal direction deviating from the ultraviolet irradiation site. Even in such a case, charged particles or the like are generated by the auxiliary discharge generated at the end of the discharge tube when the lamp is turned on. Due to the charged particles or the like, discharging occurs near the auxiliary electrode, and the discharging induces discharging at a position far from the auxiliary electrode, thereby causing discharging through the entire discharge tube. However, in such a case, there is no effect of the auxiliary discharge that stabilizes the discharge at the time of lighting from a distance away from the auxiliary electrode. Therefore, discharge nonuniformity and a spark type discharge tend to arise. As a result, problems such as a decrease in balance and instability of processing occur. In contrast, in the twelfth invention according to the present invention, the auxiliary electrode is provided over the entire length of the discharge tube in the longitudinal direction. Therefore, the charged particles produced by the auxiliary discharge and the like are uniformly distributed in the entire discharge tube. As a result, it is possible to obtain the effect of stabilizing the discharging.

In the twelfth invention, the total length in the longitudinal direction means approximately the entire length of the portion in which the discharge is generated in the discharge tube. For example, in the case where the first and second electrodes are not provided at the end of the discharge tube, and therefore a portion where no discharge is generated is provided, the portion corresponds to the twelfth invention even if the auxiliary electrode is not provided. do. This is natural considering the purpose of installing the auxiliary electrode.

As described above, the present invention can provide an ultraviolet lamp and an ultraviolet irradiation device in which a simple irradiation can obtain sufficient irradiation efficiency and the discharge container is not easily cracked.

<First Example>

EMBODIMENT OF THE INVENTION Hereinafter, the 1st Example which actualized this invention is described in detail, referring FIG. 1 and FIG.

2 is a side cross-sectional view of the excimer lamp 1 of the present embodiment, and a cross-sectional view of a surface perpendicular to the longitudinal direction of the discharge tube is shown in FIG. 2. The excimer lamp 1 is provided with a discharge tube 2. The discharge tube 2 is formed of quartz glass in the same way as the exterior portion 3 formed of quartz glass and is inserted into the interior portion 3 of the inner tube portion 4. It has a double pipe structure provided with.

The exterior portion 3 has a shape that is obtained by crushing and flattening a part of the arc of the outer circumferential wall in a elongated cylinder. That is, it is provided with the cross-section arc-shaped curved part 5, and the flat flat part 6 which connects the edges of the both ends of the arc in this curved part 5. As shown in FIG. A ball is attached to the corner portion 5A where the curved portion 5 and the flat portion 6 are joined. On the other hand, the inner tube part 4 is cylindrical with a diameter smaller than the outer part 3, and is arrange | positioned at the center position of the lateral direction on the inner wall surface of the flat part 6. The exterior portion 3 and the inner tube portion 4 are joined to each other at both ends, and the discharge gas 7 is filled in the discharge space 7 surrounded by the both tube portions 3 and 4. As the gas for discharge, for example, gas commonly used for this type of lamp, such as xenon, argon and krypton, can be used.

The discharge tube 2 is provided with a pair of electrodes 8 and 9. The first electrode 8 of these pairs of electrodes consists of a metal film fixed to the outer wall surface of the curved part 5 in the exterior part 3. And as a material of the 1st electrode 8, it is preferable to use what reflects an ultraviolet-ray. As the material of such a material, aluminum can be used, for example.

Here, the 1st electrode 8 is formed wider than the range from one side part to the other side part of the exterior part 3 along the curved part 5. Moreover, in the cross section of the ultraviolet lamp perpendicular | vertical to the longitudinal direction of the discharge tube 2, the tangent plane to an ultraviolet reflecting surface in the point of a part below one side among the ultraviolet reflecting surfaces in the 1st electrode 8 is. The direction toward the inside of the exterior part 3 is perpendicular | vertical to, and is downward rather than the direction toward the other side from one side part.

In addition, the end portion 8A of the first electrode 8 and the side end portion 6A of the flat portion 6 (in other words, the transition from the flat surface of the flat portion 6 to the curved surface with curvature) Between the boundary positions), a gap in which the first electrode 8 does not exist is formed. In other words, the 1st electrode 8 is provided in the position which receded from the junction position with the flat part 6 in the curved part 5. On the other hand, the 2nd electrode 9 paired with this 1st electrode 8 consists of nickel wire, and is inserted in the inner pipe | tube part 4 over substantially full length. Here, the second electrode 9 is provided at a position equidistant from each point on the first electrode 8.

One end of the lead wires 10 and 11 is connected to these electrodes 8 and 9, and the other end of the lead wires 10 and 11 is connected to the AC power supply 12.

Next, the operation and effect of the present embodiment configured as described above will be described.

The excimer lamp 1 is provided in an ultraviolet irradiation device (not shown) with the flat part 6 side as an exit surface. That is, as for the excimer lamp 1, in the irradiation chamber, the flat part 6 side is downward (workpiece W) on the upper side of the conveyance path | route of the conveyor which conveys the workpiece | work W to be irradiated. Side).

When carrying out the ultraviolet irradiation process to the workpiece | work W, the workpiece | work W is carried in an irradiation chamber by a conveyor. The workpiece | work W carried in is irradiated with the ultraviolet-ray by the excimer lamp 1 from the upper side. At this time, any of ultraviolet rays generated in the discharge tube (indicated by the broken arrow in the drawing) traveling in the flat part 6 direction is passed through the flat part 6 as it is and is emitted toward the work W. On the other hand, progressing in the curved portion 5 direction touches and reflects on the first electrode 8 and exits toward the work W from the flat portion 6 side.

The work W after completion of irradiation is carried out from the irradiation chamber by the conveyor and proceeds to the next step.

As described above, according to the present embodiment, the exterior portion 3 of the discharge tube 2 is provided with a flat portion 6 and a curved portion 5, and the first electrode 8 is placed on the curved portion 5. It is installed. When irradiating with the excimer lamp 1 which has such a structure, since the emission surface side is a flat surface, the distance with the workpiece | work W will be equalized over the whole emission surface. Therefore, even in the air, the loss of ultraviolet light absorbed by oxygen can be suppressed to a minimum, and the entire surface of the work W can be irradiated evenly.

In addition, when the first electrode 8 is formed of a material having a high reflectance of ultraviolet rays such as aluminum, the first electrode 8 reflects the ultraviolet rays emitted to the curved portion 5 side to form a flat portion ( 6) To fulfill the role of reflector to collect on the side (the exit surface side). As described above, since ultraviolet rays can be collected on the emission surface side without providing a reflecting plate separately, the irradiation efficiency can be improved by a simple configuration.

Further, the first electrode 8 is provided with a gap between the side edges 6A of the flat portion 6. Here, when the edge part 8A of the 1st electrode 8 reaches the irradiation surface (flat part 6), for example, the workpiece | work W is electroconductive and between the workpiece | work W and the 1st electrode 8 is carried out, for example. If a potential difference exists, there is a fear that a discharge occurs between the work W and the end portion 8A of the first electrode 8. However, in the present embodiment, since the end portion 8A of the first electrode 8 is positioned at a position receding from the irradiation surface, discharge can be avoided between the workpieces W. FIG.

In addition, the discharge tube 2 has a double tube structure including the outer portion 3 and the inner tube portion 4, and the second electrode 9 is formed inside the inner tube portion 4. According to such a structure, since an electrode does not exist in the flat part 6 (emission surface), even if an electrode is oxidized and deteriorated, the workpiece | work W is not polluted by the particle which arises from such deterioration.

In the present embodiment, the second electrode 9 is a linear electrode formed of a metal line. According to such a structure, the electric field strength becomes high around a linear electrode. In places where the electric field strength is high, the rate distribution of electrons shifts toward the high energy side, and the ionization probability of the gas for discharge increases, so that the ionization coefficient becomes large. That is, in the discharge system using such an unbalanced electric field, the vicinity of the linear electrode is in a very easy state to be discharged. Therefore, even if some nonuniformity arises in the distance between electrodes in the longitudinal direction of the discharge tube 2, discharge nonuniformity does not arise easily. In addition, both sides of the pair of electrodes have a certain area and become wider, and are conventionally susceptible to variations in the distance between the electrodes (for example, unevenness in the thickness of the dielectric, curved state or irregularities of the flat plate, etc.). Compared with a lamp, the uniformity of discharge is excellent.

Moreover, since shielding of the emitted light by the 2nd electrode 9 can be made as little as possible, the light extraction efficiency is excellent.

In addition, a 1st Example is 1st invention, 2nd invention, 3rd invention, 4th invention, 6th invention, 7th invention, 9th invention, and 11th by this invention described in "the invention of invention". It has a structure corresponding to all of the inventions. Therefore, what is described in "the start of invention" as an effect obtained by these inventions is obtained in a 1st Example.

<2nd Example>

A second embodiment of the present invention will be described below with reference to FIG. 3. The main difference from the first embodiment of the excimer lamp 20 of this embodiment is that the discharge tube 21 has a single tube structure, and the second electrode 25 is provided in the flat portion 23. It is at that point.

3, the cross section of the excimer lamp 20 of a present Example is shown. The excimer lamp 20 is provided with a discharge tube 21. The discharge tube 21 is formed of quartz glass, and has a shape in which a part of the arc of the outer circumferential wall is crushed and flattened in an elongated cylinder. In other words, the discharge tube 21 includes an arcuate curved portion 22 and a flat plate portion 23 that connects the edges of both ends of the arc in the curved portion 22.

In the curved portion 22 of the discharge tube 21, a first electrode 24 is provided in the same manner as in the first embodiment. On the other hand, the second electrode 25 is provided on the outer wall surface of the flat portion 23. The second electrode 25 is formed in a thin line in a length that extends substantially over the entire length of the discharge tube 21, and the center portion in the width direction (lateral direction) of the flat portion 23 is formed. Is placed on. One end of a lead wire is connected to these electrodes 24 and 25, and the other end of these lead wires is connected to an AC power supply device.

When using such an excimer lamp 20, similarly to 1st Example, the flat part 23 side is installed in the ultraviolet irradiation device (not shown) toward the workpiece | work W side, and an irradiation is performed. At this time, since the exit surface side is a flat surface, the distance to the work W is equalized over the entire emission surface. As a result, even in the air, the loss of ultraviolet light absorbed by oxygen can be minimized and irradiated, and the entire surface of the work W can be irradiated evenly.

In the present embodiment, the second electrode 25 is provided on the outer surface of the discharge tube in the flat portion 23. At this time, by forming the second electrode 25 in a thin line shape, the thickness of the electrode 25 can be made as minimum as necessary, and shielding of the emitted light can be reduced as much as possible. Moreover, by arrange | positioning the 2nd electrode 25 in the center position of the width direction (lateral direction) of the flat part 23, the generation of the deflection of irradiation intensity in the width direction of an irradiation surface can be avoided.

In addition, a 2nd Example is in all of 1st invention, 2nd invention, 3rd invention, 4th invention, 7th invention, 10th invention, and 11th invention by this invention described in "the invention of invention". It is equivalent structure. Therefore, what is described in "the start of invention" as an effect obtained by these inventions is obtained in a 2nd Example.

<Third Example>

A third embodiment of the present invention will be described below with reference to FIGS. 4 to 6. The main difference between the excimer lamp 30 of the present embodiment and the first embodiment lies in that the auxiliary electrode 39 is provided on the outer wall of the flat part 35.

4, sectional drawing of the excimer lamp 30 of a present Example is shown. The excimer lamp 30 is provided with a discharge tube 31. Similar to the first embodiment, the discharge tube 31 has an inner tube portion 33 formed of quartz glass and inserted into the outer portion 32 in the same way as the outer portion 32 formed of the quartz glass. It has a double tube structure.

As in the first embodiment, the exterior portion 32 has a shape in which a part of the arc of the outer circumferential wall is crushed and flattened in an elongated cylinder. That is, the curved surface part 34 and the flat part 35 which connects the edge of the both ends of the arc in this curved part 34 are provided, and the curved part 34 and the flat part 35 are provided. A ball is attached to the corner portion 34A to which is joined. On the other hand, the inner tube part 33 also has a cylindrical shape smaller in diameter than the outer part 32 similarly to the first embodiment, and has a width direction (lateral direction of the discharge tube 31) on the inner wall surface of the flat part 35. It is arranged at the center position of. The exterior part 32 and the inner tube part 33 are joined to each other at both ends, and the discharge gas 36 is filled in the discharge space 36 surrounded by both the tube parts 32 and 33.

The discharge tube 31 is provided with a pair of electrodes 37 and 38 similarly to the first embodiment. The first electrode 37 is made of an aluminum film that is fixed to the outer wall surface of the curved portion 34 in the exterior portion 32. On the other hand, like the first embodiment, the second electrode 38 is made of nickel wire and is inserted into the inner tube portion 33 over the entire length. One end of the lead wire is connected to these electrodes 37 and 38, and the other end of the lead wire is connected to an AC power supply device.

The auxiliary electrode 39 is provided on the outer surface of the exterior portion of the flat portion 35 over substantially the entire surface. This auxiliary electrode 39 assists in discharging between the pair of electrodes 37 and 38. In the present embodiment, since the flat part 35 side is an emission surface, the auxiliary electrode 39 is formed in a mesh shape so as not to block light emitted from the inside of the discharge tube 31 as much as possible. The auxiliary electrode 39 is preferably provided over the entire length of the discharge tube 31 in the longitudinal direction. This is because it is possible to stabilize the discharge over the entire length of the discharge tube 31.

When using such an excimer lamp 30, similarly to 1st Example, the flat part 35 side is installed in the ultraviolet irradiation device (not shown) toward the workpiece | work W side, and an irradiation is performed.

When a high frequency voltage is applied between the first electrode 37, the auxiliary electrode 39, and the second electrode 38 by a high frequency power source, first, in the vicinity of the second electrode 38, the second electrode and the auxiliary electrode are provided. Discharge occurs between 39. Subsequently, this discharge widens laterally along the plate surface of the flat part 35 (auxiliary discharge; see FIG. 5). Thereafter, an electric discharge occurs between the first electrode 37 and the second electrode 38, and the discharge is widened in the discharge space 36 as a whole (see FIG. 6).

In actual use of the excimer lamp 30, it is difficult to visually confirm that the auxiliary discharge and the electric discharge are occurring step by step in order to apply a high frequency AC voltage. However, by observing the discharge current related to the auxiliary discharge and the discharging using an oscilloscope, it is possible to confirm the staged occurrence of the auxiliary discharge and the discharging as described above.

Here, since the auxiliary electrode 39 is disposed closer to the second electrode 38 than the first electrode 37, the auxiliary discharge occurs first between the second electrode 38 and the auxiliary electrode 39. . Charged particles, atoms or ions in a metastable state, and photons generated by the discharge lower the voltage for generating a discharging between the first electrode 37 and the second electrode 38. As a result, the voltage at the start of the excimer lamp 30 can be reduced or the discharge can be stabilized.

In addition, in this type of lamp, there is a desire to increase the sealing gas pressure so that a high output can be obtained. However, in this way, discharge becomes unstable in general (increasing the sealing gas pressure has the same effect as increasing the distance between electrodes under a constant applied voltage). However, in the present embodiment, since the charged particles generated by the auxiliary discharge, the atoms or ions in the metastable state, and the photons can be efficiently supplied to the kitchen space uniformly, the ionization coefficient of the discharge gas existing in the kitchen space is adjusted. Can be increased. As a result, the discharging space is in a state where the discharge is likely to occur, and thus the stability of the discharge can be ensured without increasing the applied voltage.

The ultraviolet rays emitted by the discharge (indicated by dashed arrows in the figure), which proceed in the direction of the flat portion 35, are passed through the mesh of the flat portion 35 and the auxiliary electrode 39 as they are, and are emitted toward the work W. FIG. On the other hand, what goes in the direction of the curved part 34 touches the 1st electrode 37, and after it reflects, it is radiate toward the workpiece | work W from the flat part 35 side.

As described above, according to the present embodiment, the voltage at the start of the lamp can be reduced, and the discharge stability can be ensured.

Since the second electrode 38 is between the first electrode 37 and the auxiliary electrode 39, the second electrode 38 is preferably closer to the auxiliary electrode 39, and the second electrode 38 is the same as in the present embodiment. It is most preferable that the inner tube part 33 which accommodates this is in close contact with the inner wall surface of the flat part 35.

However, the arrangement of the second electrodes 38 may not necessarily be as described above. When a voltage is applied, an auxiliary discharge occurs between the second electrode 38 and the auxiliary electrode 39, and thereafter, the second electrode is positioned at a position where a discharging occurs between the first electrode 37 and the second electrode 38. If (38) is arrange | positioned, the objective of this invention can be achieved. In other words, it is an effective means to cause discharge between the second electrode 38 and the auxiliary electrode 39 before the first electrode 37 and the second electrode 38, and the first electrode 37 and When the shortest distance between the second electrode 38 is La and the shortest distance between the auxiliary electrode 39 and the second electrode 38 is Lb,

La ＞ Lb

The second electrode 38 may be disposed at a position that satisfies the relationship.

In addition, also in this embodiment, the flat part 35 is for light transmission similarly to the first embodiment, and the emission surface side is a flat surface. Therefore, since the distance with the workpiece | work W is equalized over the whole emission surface, the loss which an ultraviolet-ray is absorbed by oxygen can be minimized and irradiated even in air | atmosphere. In addition, the whole surface of the workpiece | work W can be irradiated uniformly. Moreover, since the 1st electrode 37 is formed of the material which reflects an ultraviolet-ray, the 1st electrode 37 reflects the ultraviolet-ray radiated | emitted to the curved-surface part 34 side, and the flat part 35 side (emission surface) It acts as a reflector to collect on the side). And the auxiliary electrode 39 provided in the flat part 35 is a mesh form so that the light emitted may not be interrupted | blocked. According to such a structure, similarly to the first embodiment, it is possible to collect ultraviolet rays on the emission surface side without providing a reflection plate separately, so that the irradiation efficiency can be improved with a simple configuration.

Moreover, 3rd Example is 1st invention, 2nd invention, 3rd invention, 4th invention, 5th invention, 6th invention, 7th invention, and 8th invention by this invention described in "the invention of invention". , The eleventh invention, and the twelfth invention. Therefore, what was described in "the start of invention" as an effect obtained by these inventions is obtained in 3rd Example.

Example

[Example confirming irradiation efficiency of ultraviolet ray]

1. Preparation of the lamp

<Example 1>

An excimer lamp having the same structure as in the first embodiment was produced. Aluminum was vapor-deposited so that the outer side of the curved part may be substantially covered by the cylindrical valve of the same shape as the external part 3 of 1st Example. The tubular valve is made of synthetic quartz (Sup-F310 manufactured by Shin-Etsu Sekiei Co., Ltd.), having a thickness of 2 mm, a valve length of 1000 mm, a radius of curvature of 16 mm on the outer circumferential surface of the curved portion, and a rounded corner of the curved portion joined to the flat portion. The radius of curvature of the outer circumferential surface is 5 mm. A synthetic quartz tube having an outer diameter of about 4 mm and a thickness of about 0.8 mm was placed inside the valve, and a nickel wire having a diameter of about 1 mm was inserted inside the quartz tube. Xenon gas was sealed as a discharge gas to 200 Torr in the valve, and the aluminum vapor deposition electrode was discharged by applying a high frequency voltage (peak voltage of 8 kV) of 30 kHz using the earth electrode and the nickel wire as the high voltage electrode. The discharge occurred uniformly throughout the valve.

<Comparative Example 1>

On the other hand, for comparison, a lamp having a conventional double tube structure was made. After depositing aluminum on the outer circumferential surface of the valve having an outer diameter of 32 mm, the mesh type electrode (opening ratio of 80%) was formed by etching. Inside the valve, a synthetic quartz tube having the same structure as in the above embodiment was placed, and a nickel wire was inserted therein. The xenon gas was sealed as a discharge gas to 200 Torr in the valve, and a high frequency voltage (peak voltage (8 kV)) of 30 kHz was applied and discharged using the aluminum vapor deposition electrode as the earth electrode and the nickel wire as the high voltage electrode.

2. Lighting test

The lamps of Examples and Comparative Examples were turned on in the air without using an irradiation mechanism, and the UV sensor was scanned in a horizontal direction at a speed of 3 m / min at a position of 3 mm just below the lamp. As a result of comparing the accumulated light amounts, it was confirmed that the lamp side of the example was about three times larger than the lamp of the comparative example, and it was possible to efficiently irradiate ultraviolet rays to the irradiated object.

[Example confirming the effect by the auxiliary electrode]

<Example 2>

An excimer lamp having the same structure as in the third embodiment was made. A nickel film (outer electrode) having a length of 1000 mm and a thickness of 0.2 mm was fixed to a cylindrical valve having the same shape as that of the exterior portion 32 of the third embodiment so as to substantially cover the outer surface of the curved portion. The tubular valve is made of synthetic quartz (SUPRASIL-F310 manufactured by Shin-Etsu Sekiei Co., Ltd.), has a thickness of 2 mm, a valve length of 1100 mm, a radius of curvature of the outer circumferential surface of the curved portion at 16 mm, and a corner portion at which the curved portion joins the flat portion. The radius of curvature of the rounded outer circumferential surface of is 5mm. Inside the valve, a synthetic quartz tube having an outer diameter of about 5 mm and an inner diameter of about 2 mm was placed, and a nickel wire (inner electrode) having a diameter of about 1.8 mm was inserted inside the quartz tube.

Moreover, in the cylindrical valve, a SUS mesh plate (auxiliary electrode) of 22 mm in width, 1000 mm in length, and 0.2 mm in thickness was fixed so as to substantially cover the outer surface of the flat portion. The distance from the central axis of the nickel wire to the inner surface (fixed surface with the flat portion) of the mesh plate was about 5 mm.

The xenon gas was sealed as 46.7 KPa as a discharge gas in the valve, and the nickel film and the mesh plate were discharged by applying a substantially rectangular high frequency voltage of 70 kHz as the earth electrode and the nickel wire as the high voltage electrode.

When the applied voltage is gradually raised, auxiliary discharge occurs along the inner wall surface of the flat portion at a peak value of about 2 kV, and then the kitchen between the inner electrode (nickel wire) and the outer electrode (nickel film) at about 5.5 kV. Metastasis occurred. It was also found that discharging was not inhibited by auxiliary discharge. That is, the minimum required voltage for starting the lamp was 5.5 kV. On the other hand, for comparison, the same lamp as in Example 2 was produced and tested except that no mesh plate (auxiliary electrode) was provided. When no voltage of about 10 kV was applied as the peak value, no electric discharge occurred. In this manner, in the lamp provided with the auxiliary electrode, it was possible to generate a discharging power at an applied voltage of about 1/2 compared to the lamp without the auxiliary electrode.

In addition, in the lamp of Example 2, when the peak voltage after startup was kept constant at 5.5 kV, the discharge stability was examined. There was no spark type discharge or deflection deflection, and stable discharge could be realized immediately after startup. On the other hand, when the same experiment was performed with the lamp which does not have an auxiliary electrode, a spark generate | occur | produced and the discharge nonuniformity produced.

<Other Example>

The technical scope of the present invention is not limited to the above-described embodiments. For example, the technical scope of the present invention is also described below.

(1) In each of the above embodiments, the first electrode 8 is provided with a gap between the periphery of the flat portion 6, but is discharged between the work and the electrode, for example, when the work is a nonmetal. In the case where there is no concern, the entire surface of the curved portion may be covered by one electrode.

(2) In the second embodiment, the second electrode 25 was formed in a thin line shape. For example, the second electrode may be formed in a mesh shape over the entire flat portion, and a plurality of thin metal foils may be formed. May be formed in a parallel stripe shape.

(3) In the first embodiment, the discharge tube 2 has a double tube structure having an exterior portion 3 and an inner tube portion 4, and the second electrode 9 is provided inside the inner tube portion 4, However, the present invention is not limited to this case. For example, like the excimer lamp 40 shown in FIG. 7, the discharge tube 41 has a single tube structure similar to that of the second embodiment, and the second electrode 42 formed in a rod shape has an inner tube portion. It may not be accommodated and may be a structure arranged inside the discharge tube 41 while being exposed. Alternatively, the structure in which the insulating film is coated on the rod-shaped second electrode may be arranged inside the discharge tube.

(4) In the third embodiment, the second electrode formed in the shape of a rod may not be accommodated in the inner tube portion, but may be a structure arranged inside the discharge tube while being exposed. In this case, it is most preferable that the second electrode is almost in close contact with the inner surface of the flat portion in the discharge tube. However, when a voltage is applied between the electrodes, an auxiliary discharge occurs between the second electrode and the auxiliary electrode, and thereafter, the second electrode. It is the same as in the case of the third embodiment that it is preferable that the second electrode is disposed at the position where the electric discharge occurs between the electrode and the first electrode.

(5) In each of the above embodiments, the connecting portion between the flat portion and the curved portion is a curved surface with curvature, but may be connected to each other through a partially flat surface.

(6) In the third embodiment, although the flat part 35 is an exit surface through which light can pass, for example, the first electrode 37 can transmit light such as a mesh or a thin wire. If it forms in the shape which exists, light can also be emitted from the curved-surface part side.

Incidentally, the above embodiment has been described with respect to the excimer lamp, but the present invention is not limited to the excimer lamp, and may be an ultraviolet lamp other than an excimer lamp such as a mercury lamp.

This application is based on the JP Patent application 2005-221143 of July 29, 2005, and JP Patent application 2006-031051 of February 8, 2006, These content is integrated in this invention by using it here.

1 is a side sectional view of an excimer lamp of a first embodiment.

2 is a cross-sectional view of the excimer lamp of the first embodiment.

3 is a cross-sectional view of the excimer lamp of the second embodiment.

4 is a cross-sectional view of the excimer lamp of the third embodiment.

Fig. 5 is a cross-sectional view showing a state in which auxiliary discharge is occurring on the inner side of the flat portion in the excimer lamp of the third embodiment.

FIG. 6 is a cross-sectional view showing a state in which a discharging occurs between the first electrode and the second electrode in addition to the auxiliary discharge in the excimer lamp of the third embodiment.

7 is a cross-sectional view of an excimer lamp of another embodiment.

8 is a cross-sectional view of a lamp house in which a conventional excimer lamp is accommodated.

9 is a cross-sectional view of an example of a discharge tube of an ultraviolet lamp according to the present invention.

It is sectional drawing of an example of the discharge tube of the ultraviolet lamp by this invention.

It is a figure which shows the side part of the discharge tube of the ultraviolet lamp by this invention.

12 is a sectional view of an ultraviolet lamp of a comparative example having a cylindrical discharge tube.

It is a figure which shows the "near the center part of the flat part" in 6th invention by this invention.

It is a figure which shows the "near the center part of the flat part" in 10th invention by this invention.

1, 20, 30, 40... Excimer lamp

2, 21, 31... discharge pipe

3, 32... Exterior

4, 33... Inner tube

5, 22, 34, 205... Curved part

2, 23, 35, 201... Flat part

8, 24, 37... First electrode

9, 25, 38, 42... Second electrode

Claims (11)

In the ultraviolet lamp having a discharge tube formed in a cylindrical shape, The outer circumferential wall of the discharge tube is provided with a curved portion and a flat portion for transmitting ultraviolet rays at positions facing each other, The curved portion is formed so that the surface of the inner side of the discharge tube is a concave surface, An ultraviolet reflecting member is provided in the curved portion, The ultraviolet reflecting member is formed wider than the range from one side of the discharge tube to the other side along the curved portion, The ultraviolet reflecting member is a first electrode for generating a discharge for generating ultraviolet rays, In the cross section of the said ultraviolet lamp perpendicular | vertical to the longitudinal direction of the said discharge tube, it is perpendicular | vertical to the tangent plane to the said ultraviolet reflecting surface in the point of the part below the one side among the ultraviolet reflecting surfaces of the said ultraviolet reflecting member. And a direction toward the inside of the discharge tube is lower than a direction toward the other side from the one side. delete The method of claim 1, The first electrode is for earth connection, The first electrode is provided on the outer surface of the curved portion, The ultraviolet lamp in which the 2nd electrode for high voltage connection is provided in the said discharge tube. The method of claim 1, Inside the discharge tube, a linear second electrode extending in the longitudinal direction of the discharge tube is provided, The second electrode is provided in the vicinity of the center of the flat portion for ultraviolet transmission, An ultraviolet lamp, configured to generate a discharging between the first electrode and the second electrode. The method of claim 4, wherein The first electrode is arcuate in cross section, An ultraviolet lamp having a linear second electrode extending in the longitudinal direction of the discharge tube at a position equidistant from each point on the cross section of the first electrode. The method of claim 1, Inside the discharge tube, a linear second electrode extending in the longitudinal direction of the discharge tube is provided, Configured to generate a discharging between the first electrode and the second electrode, Auxiliary electrode is provided on the UV transmission flat portion, An ultraviolet lamp, configured to generate an auxiliary discharge between the second electrode and the auxiliary electrode. The method of claim 1, Inside the discharge tube, a linear second electrode extending in the longitudinal direction of the discharge tube is provided, The second electrode is provided in the vicinity of the center of the flat portion for ultraviolet transmission, Configured to generate a discharging between the first electrode and the second electrode, The ultraviolet lamp which is not provided with electrodes other than a said 2nd electrode in the said ultraviolet-ray flat part. The method of claim 1, The first electrode is provided on the outer surface of the curved portion, The ultraviolet lamp in which the said 1st electrode is not provided in the vicinity of the boundary of the said flat part for ultraviolet transmission and the said curved part among the outer surfaces of the said curved part. The method of claim 6, The said auxiliary electrode is an ultraviolet lamp provided over the full length of the longitudinal direction of the said discharge tube. The method of claim 1, The ultraviolet lamp is an excimer lamp. The ultraviolet irradiation device using the ultraviolet lamp of any one of Claims 1, 3, 4, 5, 6, 7, 8, 9 and 10.

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