TWI798381B - Shield discharge lamp, ultraviolet irradiation unit, and ultraviolet irradiation device - Google Patents

Abstract

The present invention provides a shield discharge lamp, an ultraviolet irradiation unit, and an ultraviolet irradiation device that suppress defects caused by wear or peeling of a reflective film. A shield discharge lamp includes a cylindrical luminous tube, internal electrodes, and a reflective film. The luminous tube is sealed with gas to allow ultraviolet light to pass through. The internal electrodes are arranged inside the luminous tube, and the helical conductor extends in the length direction of the luminous tube. The reflective film is arranged on the inner surface of the luminous tube to reflect the ultraviolet light toward the inside of the luminous tube. The luminous tube has a plurality of recesses that restrict the movement of the internal electrodes in a portion different from the reflective film. The diameter d [mm] of the concave portion and the wire diameter D [mm] of the internal electrode have a relationship of d≦10D.

Description

Shield discharge lamp, ultraviolet irradiation unit, and ultraviolet irradiation device

Embodiments of the present invention relate to a barrier discharge lamp, an ultraviolet irradiation unit, and an ultraviolet irradiation device.

Conventionally, shield discharge lamps used for the purpose of cleaning or modifying substrates are known. The barrier discharge lamp utilizes a dielectric barrier discharge generated by connecting a spiral internal electrode disposed inside a luminous tube as a dielectric and an external electrode disposed outside the luminous tube to an AC power source. , to emit ultraviolet light with a specific wavelength corresponding to the gas that has been accommodated inside the luminous tube. The radiated ultraviolet light is reflected by the reflective film provided on the inner surface of the arc tube so as to irradiate a predetermined portion.

[Prior art literature] [Patent Document] [Patent Document 1] Japanese Patent Laid-Open No. 2013-211164

[Problem to be Solved by the Invention] In the shield discharge lamp as described above, for example, the reflective film is worn or peeled off due to displacement of the internal electrodes, and the illuminance of the emitted ultraviolet light may decrease.

The problem to be solved by the present invention is to provide a shield discharge lamp, an ultraviolet irradiation unit, and an ultraviolet irradiation device capable of suppressing defects caused by abrasion or peeling of a reflective film.

[Technical means to solve the problem] According to one embodiment, the present invention provides a shielded discharge lamp including: a cylindrical arc tube, internal electrodes, and a reflective film. In the barrier discharge lamp, a barrier discharge is performed between an internal electrode provided inside the arc tube and an external electrode provided near the arc tube. The luminous tube is sealed with gas, and allows ultraviolet light to pass through. The internal electrodes are disposed inside the luminous tube, and the helical conductor extends in the longitudinal direction of the luminous tube. The reflective film is arranged on the inner surface of the luminous tube to reflect the ultraviolet light toward the inside of the luminous tube. The luminous tube has a plurality of recesses that restrict the movement of the internal electrodes in a portion different from the reflective film. The diameter d [mm] of the concave portion and the wire diameter D [mm] of the internal electrode have a relationship of d≦10D. The external electrodes are provided on the outer surface side of the luminous tube corresponding to the inner surface provided with the reflective film.

[Effect of the invention] According to the present invention, troubles caused by abrasion or peeling of the reflective film can be suppressed.

The shield discharge lamp 1 of the embodiment described below includes a cylindrical arc tube 2 , an internal electrode 3 , and a reflective film 5 . Barrier discharge lamp 1 performs barrier discharge between internal electrode 3 provided inside arc tube 2 and external electrode 6 provided near arc tube 2 . The luminous tube 2 is sealed with gas, and allows ultraviolet light to pass through. The internal electrode 3 is disposed inside the arc tube 2 , and the spiral conductor extends in the longitudinal direction of the arc tube 2 . The reflective film 5 is provided on the inner surface 2 a of the arc tube 2 to reflect ultraviolet light toward the inside of the arc tube 2 . The arc tube 2 has a plurality of recesses 4 that restrict the movement of the internal electrodes 3 in a portion different from the reflective film 5 . The reflective film 5 is arranged within a range of 180° or more in the circumferential direction of the arc tube 2 . The diameter d [mm] of the concave portion 4 and the wire diameter D [mm] of the internal electrode 3 have a relationship of d≦10D.

In addition, in the embodiment described below, the inner surface 4 a of the concave portion 4 protrudes toward the inside of the arc tube 2 and contacts the internal electrode 3 .

In the embodiment described below, the diameter d [mm] of the recess 4 and the pitch P [mm] of the internal electrodes 3 in the tube axis direction of the arc tube 2 have a relationship of d≦P.

In addition, in the embodiment described below, the external electrode 6 is provided on the outer surface 2 b side of the arc tube 2 corresponding to the inner surface 2 a provided with the reflective film 5 . The external electrode 6 is a heat sink made of aluminum or stainless steel.

In addition, the ultraviolet irradiation unit 10 of the embodiment described below includes the shield discharge lamp 1 and the external electrode 6 . In addition, the angle θ1 of the reflective film 5 in the embodiment described below in the circumferential direction of the arc tube 2 is 180 [°] or more. In addition, the angle θ1 in the circumferential direction of the arc tube 2 of the reflective film 5 of the embodiment described below is 200 [°] to 250 [°]. In addition, the angle θ2 in the circumferential direction of the external electrode 6 in the embodiment described below is in the range of 180[°] to 330[°].

In addition, the ultraviolet irradiation device 100 of the embodiment described below includes the ultraviolet irradiation unit 10 and the housing member 50 that accommodates the ultraviolet irradiation unit 10 .

In addition, the shield discharge lamp 1 of the embodiment described below includes a cylindrical arc tube 2 , an internal electrode 3 , a reflective film 5 , and an external electrode 6 . The luminous tube 2 is sealed with gas, and allows ultraviolet light to pass through. The internal electrode 3 is disposed inside the arc tube 2 , and the spiral conductor extends in the direction of the tube axis of the arc tube 2 . The reflective film 5 is provided on the inner surface 2 a of the arc tube 2 to reflect ultraviolet light toward the inside of the arc tube 2 . The external electrode 6 is provided on the outer surface 2b side of the arc tube 2 corresponding to the inner surface 2a provided with the reflective film 5 . The arc tube 2 has a plurality of recesses 4 that restrict the movement of the internal electrodes 3 in a portion different from the reflective film 5 . The diameter d [mm] of the concave portion 4 and the wire diameter D [mm] of the internal electrode 3 have a relationship of d≦10D.

Hereinafter, embodiments of the present invention will be described based on the drawings. In addition, embodiment shown below does not limit the technology disclosed by this invention.

[implementation mode] FIG. 1 is a plan view showing a shield discharge lamp according to an embodiment, and FIG. 2 is an AA' sectional view of FIG. 1 . As shown in FIGS. 1 and 2 , a shield discharge lamp 1 according to the embodiment includes a light emitting tube 2 , an internal electrode 3 , and a reflection film 5 . In addition, a barrier discharge is performed with the external electrode 6 provided in the vicinity of the shield discharge lamp 1 . In addition, the "nearby" mentioned here is not limited to the case where the shield discharge lamp 1 is provided in contact with the external electrode 6, For example, the case where the shield discharge lamp 1 and the external electrode 6 are provided with a space|interval is also included. In addition, in the present embodiment, the outer electrode 6 is provided in the vicinity of the shield discharge lamp 1, but the shield discharge lamp 1, more specifically, the arc tube 2 and the outer electrode 6 may be combined. The form is called "shielded discharge lamp".

1 and 2 illustrate a three-dimensional orthogonal coordinate system including the Z axis in which the irradiation direction is the positive direction for easy understanding of the description.

The arc tube 2 is a cylindrical member that transmits ultraviolet light. As a material of the arc tube 2 , for example, synthetic quartz having a high vacuum ultraviolet ray transmittance at a wavelength of 200 [nm] or less is exemplified. In addition, both ends in the tube axial direction (X-axis direction) of the arc tube 2 are held by a sealing member having a rod structure, and are hermetically sealed. For example, the length in the tube axis direction of the arc tube 2 can be set to 750 [mm], and the inner diameter of the arc tube 2 can be set to 40 [mm].

In addition, gas is sealed inside the arc tube 2 . The gas is, for example, xenon gas of 80 [kPa] to 200 [kPa]. Furthermore, the gas may contain, for example, one of krypton, xenon, argon, neon, etc., or a combination of a plurality of gases. Furthermore, the gas may contain, for example, a halogen gas as needed. The arc tube 2 can emit ultraviolet light (excimer light) having a specific peak wavelength corresponding to the type of enclosed gas.

The internal electrodes 3 are arranged inside the arc tube 2 . The helical conductor of the internal electrode 3 extends in the direction of the tube axis of the arc tube 2 . Internal electrode 3 is formed of, for example, a material containing tungsten. Specifically, 50 [%] or more of the total components of the internal electrodes 3 is tungsten. In particular, if doped tungsten obtained by adding potassium or the like to tungsten is used as the internal electrode 3, higher dimensional stability can be obtained. For example, the wire diameter D of the internal electrode 3 can be set to 0.8 [mm], and the winding diameter (outer diameter) of the internal electrode 3 can be set to 38 [mm].

The reflective film 5 is provided on the inner surface 2 a of the arc tube 2 to reflect ultraviolet light toward the inside of the arc tube 2 . As a material of the reflective film 5, silicon dioxide is exemplified, for example. In addition, the reflective film 5 is not limited to silicon dioxide, and may include, for example, a material containing ultraviolet scattering particles such as aluminum oxide. The reflective film 5 is arranged such that the angle θ1 in the circumferential direction of the arc tube 2 falls within a range of, for example, 180 [°] or more.

The reflective film 5 can change the peak value of the ultraviolet illuminance and the integrated light quantity corresponding to the angle θ1 in the circumferential direction of the arc tube 2 . FIG. 3 is a diagram for explaining changes in irradiation characteristics according to angles in the circumferential direction of the reflective film. As shown in FIG. 3 , the greater the angle θ1 in the circumferential direction of the arc tube 2 is, the greater the peak value of the ultraviolet illuminance is. On the other hand, the larger the angle θ1 is, the smaller the emission area is, so the integrated light quantity increases until it reaches a maximum value, and then decreases. In particular, in applications such as surface modification and light dry cleaning in which the integrated light quantity is an important index, the angle θ1 can be set within a range of 200[°] to 250[°], for example.

The external electrode 6 is provided on the outer surface 2b side of the arc tube 2 corresponding to the inner surface 2a of the arc tube 2 on which the reflective film 5 is provided. The external electrode 6 also serves as a heat sink for dissipating heat from the shielded discharge lamp 1 which has become heated, and may be made of aluminum or stainless steel, for example. Furthermore, a flow path through which a liquid or gas refrigerant flows may be provided inside the external electrode 6 to further improve heat dissipation. The external electrode 6 and the arc tube 2 may be in contact with each other or may be separated, but if the external electrode 6 is brought into contact with the arc tube 2, heat dissipation can be improved. In addition, in the example shown in FIG. Although they are generally different from each other and shown in the illustrations, they are not limited thereto, and may be the same. In addition, in the example shown in FIG. 2 , the angle θ2 in the circumferential direction of the external electrode 6 is, for example, 238 [°], but it is not limited thereto. The angle θ2 in the circumferential direction of the external electrode 6 can be set within a range of, for example, 180[°] to 330[°].

Here, the conventional shield discharge lamp will be described. In the conventional shield discharge lamp, the internal electrodes are supported only by both ends of the arc tube in the tube axis direction. Therefore, in the central portion in the tube axis direction, the internal electrode may be displaced due to, for example, vibration caused by an external force or the internal electrode's own weight. At this time, for example, if the displaced internal electrodes contact the reflective film, the reflective film may be worn or peeled off, resulting in problems such as a drop in illuminance.

Therefore, the arc tube 2 of the shield discharge lamp 1 of the embodiment has a plurality of recesses 4 . That is, in the shield discharge lamp 1 according to the embodiment, as shown in FIG. 2 , the inner surface 4 a of the concave portion 4 protrudes toward the inside of the arc tube 2 and contacts the internal electrode 3 . As a result, the movement of the internal electrode 3 is restricted not only at both ends in the tube axial direction but also at multiple locations in the central portion, and abrasion or peeling of the reflective film 5 accompanying displacement of the internal electrode 3 is suppressed. Furthermore, the internal electrode 3 may be in contact with the reflective film 5 or may be separated from the reflective film 5 .

In addition, the concave portion 4 is provided on a different portion from the reflective film 5 . Thereby, the possibility of peeling or chipping of the reflective film 5 accompanying the formation of the recessed part 4 can be prevented before it happens.

In addition, the diameter d [mm] of the concave portion 4 and the wire diameter D [mm] of the internal electrode 3 have a relationship of d≦10D. Here, the "diameter d of the recess 4" refers to a value at which the outer edge of the recess 4 in contact with the outer surface 2b of the arc tube 2 has the largest width in the tube axis direction (X-axis direction). Furthermore, if d>10D, since the area where the arc tube 2 is deformed when the concave portion 4 is formed becomes large, the internal electrodes 3 are deformed, and the pitch P of the internal electrodes 3 becomes uneven, which is not preferable. In addition, if d>10D, the area for deforming the arc tube 2 becomes large, and thus the step of deforming the arc tube 2 takes time, which is not preferable. Therefore, it is desirable that d≦10D.

In addition, the diameter d [mm] of the concave portion 4 and the pitch P [mm] of the internal electrodes 3 in the tube axial direction of the arc tube 2 preferably have a relationship of d≦P. This point is demonstrated using FIG. 4A and FIG. 4B.

4A and 4B are diagrams for explaining differences in illuminance characteristics depending on the shape of the concave portion. Fig. 4A is a diagram illustrating an example of the case of d≦P, and Fig. 4B is a diagram illustrating an example of the case of d>P, which correspond to the BB' cross section of the shielded discharge lamp 1 shown in Fig. 2 picture.

The ultraviolet light that has been emitted from the inside of the arc tube 2 is scattered in the concave portion 4 . As shown in FIG. 4B , as the diameter d [mm] of the concave portion 4 increases, the area where the ultraviolet light is scattered increases, thereby possibly reducing the illuminance of ultraviolet rays irradiated on the irradiated body. Therefore, by forming the concave portion 4 having the relationship of d≦P as shown in FIG. 4A , troubles associated with scattering of ultraviolet light in the concave portion 4 can be reduced. Furthermore, if the diameter d [mm] of the concave portion 4 is too small, the amount of deformation of the arc tube 2 accompanying the formation of the concave portion 4 may locally increase, and a through hole may be formed in the concave portion 4 . Therefore, for example, it is preferable to form the concave portion 4 so that D<d≦P.

[Evaluation Test] A vibration test was performed using a trial product of the shield discharge lamp, and the difference in the irradiation characteristics depending on the presence or absence of the concave portion 4 was evaluated. The outline of the evaluation test is shown in FIG. 5 . In addition, the vibration test was performed according to Japanese Industrial Standards (JIS) Z0232. Compare the illuminance characteristics (Ultraviolet (UV) illuminance change rate) and electrical characteristics (current change rate) before and after the vibration test. According to the measurement error in the preliminary test, if the change rate is below 2[%], then It was judged to be no problem. In addition, the number of tests was set to n=3p.

FIG. 6 shows the results of the evaluation test without the recess 4 , and FIG. 7 shows the results of the evaluation test with the recess 4 . As shown in FIG. 6 , in the shielded discharge lamp without the concave portion 4, the change rates of the illuminance characteristics and electrical characteristics of samples 1 to 3 before and after the test all exceeded 2%, suggesting that the wear of the reflective film or Undesirable conditions caused by stripping. On the other hand, as shown in Fig. 7, in the shield discharge lamp having the recess 4, the change rates of the illuminance characteristics and electrical characteristics of samples 4 to 6 before and after the test were all below 2 [%], and the results of the recess 4The resulting improvement effect was confirmed.

[Ultraviolet irradiation device] 8A and 8B are diagrams showing an ultraviolet irradiation device having an ultraviolet irradiation unit according to an embodiment. FIG. 8A is a view viewed from the tube axis direction (Y-axis direction), and FIG. 8B is a view viewed from the X-axis direction. As shown in FIGS. 8A and 8B , the ultraviolet irradiation device 100 according to the embodiment has a housing member 50 and a lighting device 60 . One or more ultraviolet irradiation units 10 are housed in the housing member 50 . The storage member 50 is an example of a storage unit.

The ultraviolet irradiation unit 10 has a shield discharge lamp 1 and an external electrode 6 . Furthermore, when the shield discharge lamp 1 , more precisely, the combination of the arc tube 2 and the external electrode 6 is referred to as a “shield discharge lamp”, the shield discharge lamp 1 corresponds to the ultraviolet irradiation unit 10 .

The lighting device 60 is arranged on the back side of the housing member 50 and is electrically connected to the internal electrode 3 and the external electrode 6 provided inside the arc tube 2 of the ultraviolet irradiation unit 10 . By arranging the lighting device 60 on the back side of the housing member 50 as described above, the wiring length between the lighting device 60 and the ultraviolet irradiation unit 10 can be shortened. Furthermore, the arrangement of the lighting device 60 is not limited to the pattern shown in FIGS. 8A and 8B , and the lighting device 60 may be installed outside the ultraviolet irradiation device 100 , for example.

In addition, the lighting device 60 includes an inverter capable of outputting high voltage and high frequency, and is configured to be able to supply electric power from an AC power supply (not shown) to the ultraviolet irradiation unit 10 . The lighting device 60 can apply, for example, a sine wave with a frequency of 120 [kHz] to light the arc tube 2 of the ultraviolet irradiation unit 10 with a lamp power of about 1 [kW].

As described above, the shield discharge lamp 1 of the embodiment includes the cylindrical arc tube 2 , the internal electrode 3 , and the reflective film 5 . Barrier discharge lamp 1 performs barrier discharge between internal electrode 3 provided inside arc tube 2 and external electrode 6 provided near arc tube 2 . The luminous tube 2 is sealed with gas, and allows ultraviolet light to pass through. The internal electrode 3 is disposed inside the arc tube 2 , and the spiral conductor extends in the longitudinal direction of the arc tube 2 . The reflective film 5 is provided on the inner surface 2 a of the arc tube 2 to reflect ultraviolet light toward the inside of the arc tube 2 . The arc tube 2 has a plurality of recesses 4 that restrict the movement of the internal electrodes 3 in a portion different from the reflective film 5 . The diameter d [mm] of the concave portion 4 and the wire diameter D [mm] of the internal electrode 3 have a relationship of d≦10D. Thereby, troubles caused by abrasion or peeling of the reflective film can be suppressed.

In the embodiment, the diameter d [mm] of the concave portion 4 and the pitch P [mm] of the internal electrodes 3 in the tube axial direction of the arc tube 2 have a relationship of d≦P. Accordingly, troubles associated with scattering of ultraviolet light in the concave portion 4 can be reduced.

In addition, the external electrode 6 of the embodiment is provided on the outer surface 2 b side of the arc tube 2 corresponding to the inner surface 2 a provided with the reflective film 5 . The external electrode 6 is a heat sink made of aluminum or stainless steel. Thereby, heat dissipation can be ensured without separately providing a heat dissipation member.

Although the embodiment of the present invention has been described, the embodiment is presented as an example and is not intended to limit the scope of the invention. The embodiment can be implemented in other various forms, and various omissions, substitutions, and changes can be made without departing from the scope of the invention. Embodiments and modifications thereof are included in the invention described in the claims and their equivalents, as well as being included in the scope or spirit of the invention.

1:Shield discharge lamp 2: LED 2a: the inner surface of the luminous tube 2 2b: the outer surface of the luminous tube 2 3: Internal electrodes 4: Concave 4a: inner surface of recess 4 5: Reflective film 6: External electrodes 10: UV irradiation unit 50: Containment Components 60: Lighting device 100: Ultraviolet irradiation device d: diameter D: wire diameter P: Pitch X, Y, Z: axes θ1, θ2: Angle

Fig. 1 is a plan view showing a shield discharge lamp according to an embodiment. FIG. 2 is an AA' sectional view of FIG. 1 . FIG. 3 is a diagram for explaining changes in irradiation characteristics according to angles in the circumferential direction of the reflective film. 4A and 4B are diagrams for explaining differences in illuminance characteristics depending on the shape of the concave portion. FIG. 5 is a diagram showing the outline of an evaluation test. FIG. 6 is a graph showing the results of an evaluation test without a concave portion. Fig. 7 is a graph showing the results of an evaluation test when there are recesses. 8A and 8B are diagrams showing an ultraviolet irradiation device having an ultraviolet irradiation unit according to an embodiment.

1:Shield discharge lamp

2: LED

3: Internal electrodes

4: Concave

6: External electrodes

d: diameter

D: wire diameter

X, Y, Z: axes

Claims (10)

A shielded discharge lamp, comprising: a cylindrical luminous tube, sealed with gas, and allowing ultraviolet light to pass through; an internal electrode, arranged inside the luminous tube, and a spiral conductor in the direction of the tube axis of the luminous tube extending; and a reflective film disposed on the inner surface of the luminous tube to reflect the ultraviolet light toward the inside of the luminous tube; Barrier discharge is performed between the external electrodes provided on the outer surface side of the tube. The barrier discharge lamp is characterized in that the luminous tube has a plurality of barriers that restrict the movement of the internal electrodes on a part different from the reflective film. In the concave portion, the diameter d [mm] of the concave portion has a relationship of d≦10D with the wire diameter D [mm] of the internal electrode. In the shielded discharge lamp described in Claim 1, the inner surface of the concave portion protrudes toward the inner side of the light emitting tube and abuts against the internal electrode. The shielded discharge lamp as described in claim 1 or claim 2, wherein the diameter d [mm] and the pitch P [mm] of the internal electrodes in the tube axis direction have a relationship of d≦P. The shielded discharge lamp as described in item 1 or item 2 of the scope of patent application, wherein the external electrode is a heat sink made of aluminum or stainless steel, which is arranged on the inner surface corresponding to the inner surface on which the reflective film is arranged. the outer surface side of the luminous tube. The shielded discharge lamp according to claim 1 or 2, wherein the angle θ1 of the reflective film in the circumferential direction of the arc tube is 180[°] or more. As for the shielded discharge lamp described in item 1 or item 2 of the scope of patent application, wherein the angle θ1 of the reflective film in the circumferential direction of the light-emitting tube is 200[°]~250[°]. The shielded discharge lamp as described in claim 1 or claim 2, wherein the angle θ2 of the outer electrode in the circumferential direction is in the range of 180[°]~330[°]. An ultraviolet irradiation unit, characterized by comprising: the shielding discharge lamp described in any one of the first to seventh items of the scope of patent application; and the external electrode. An ultraviolet irradiation device, characterized by comprising: the ultraviolet irradiation unit as described in item 8 of the scope of the patent application; and a storage part for storing the ultraviolet irradiation unit. A shielded discharge lamp, which is characterized in that it comprises: a cylindrical luminous tube, which is sealed with gas, and allows ultraviolet light to pass through; an internal electrode is arranged inside the luminous tube, and a spiral conductor is connected to the tube of the luminous tube extending in the axial direction; a reflective film disposed on the inner surface of the luminous tube to reflect the ultraviolet light toward the interior of the luminous tube; and an external electrode disposed on the inner surface with the reflective film The surface corresponds to the outer surface side of the light emitting tube; The luminous tube has a plurality of recesses that restrict the movement of the internal electrodes on a portion different from the reflective film, and the diameter d [mm] of the recesses has the same relationship with the wire diameter D [mm] of the internal electrodes. d≦10D relationship.

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