Ultraviolet irradiation device

Abstract

The invention provides an ultraviolet irradiation device with high extraction efficiency of ultraviolet rays. An ultraviolet irradiation device is provided with: a housing; a light extraction surface provided on a side surface of the case; the excimer lamp is provided with a straight-tube-shaped light-emitting tube accommodated in the box body, and a first electrode and a second electrode which are separated from each other in a first direction parallel to the tube axis of the light-emitting tube and are used for applying voltage to the light-emitting tube; and a reflection member which has a first reflection surface that faces the center of the light emitting tube and reflects ultraviolet light having a component traveling in the first direction, and which reflects at least a portion of the ultraviolet light emitted by the excimer lamp. The first reflecting surface of the reflecting member is disposed between a first reference point and a second reference point in the first direction, the first reference point being located in the vicinity of a first end of the light emitting tube on the first electrode side, and the second reference point being located in the vicinity of a second end opposite to the first end.

Description

Technical Field

[0001] The present invention relates to an ultraviolet irradiation device. Background Art

[0002] Conventionally, there has been known a technique of inactivating, for example, bacteria or viruses present in a space by irradiating ultraviolet rays. Here, "inactivation" is a concept including killing bacteria or causing the infectivity and toxicity of viruses to be lost. In recent years, with the spread of infectious diseases represented by COVID-19, attention to hygiene management has been significantly increased, and more efficient inactivation treatment of bacteria or viruses has been required. Therefore, the present applicant has proposed, for example, an ultraviolet irradiation device that can be used for the above-mentioned inactivation and other purposes (see Patent Document 1 below).

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Patent No. 6940033 Gazette Summary of the Invention

[0006] Technical Problem to be Solved by the Invention

[0007] As the ultraviolet irradiation device, there is known a configuration in which a light source such as an excimer lamp that emits ultraviolet rays is disposed in a box as described in the above Patent Document 1. Figure 15 is a perspective view showing the main body housing portion 2a and the lid portion 2b of the box 2 disassembled in the ultraviolet irradiation device 100 of Patent Document 1. In Figure 15 an X - Y - Z coordinate system is also described, in which the tube axis direction of the light emitting tube 3 of the excimer lamp is set as the X direction, and the plane orthogonal to the X direction is set as the YZ plane. The ultraviolet rays emitted from the excimer lamp are taken out of the box 2 from the light extraction surface 10 provided on the box 2 and irradiate the space or object to be irradiated.

[0008] Figure 15 In the excimer lamp having the configuration shown, by applying a voltage to a pair of electrode blocks (11, 12) arranged in contact with the wall surface of the light emitting tube 3, ultraviolet rays are emitted from the light emitting tube 3. At this time, since the ultraviolet rays travel in all directions, the ultraviolet rays emitted from the excimer lamp include those that do not directly travel to the light extraction surface 10 provided on the box 2. From the viewpoint of efficiently irradiating the space or the like of the irradiation object with ultraviolet rays, it is preferable to take out more ultraviolet rays from the light extraction surface 10 with respect to the total amount of the ultraviolet rays emitted from the excimer lamp.

[0009] Patent Document 1 proposed a solution to reduce the incident angle of ultraviolet rays with respect to the optical filter 21 in view of the characteristics of the optical filter 21 disposed on the light extraction surface 10. More specifically, it is a configuration in which tapered surfaces (11b, 12b) inclined with respect to the light extraction surface 10 are provided on the electrodes (11, 12) of the light-emitting tube 3 on which the excimer lamp is mounted. Thereby, the ultraviolet rays incident on the tapered surface are reflected toward the light extraction surface 10 and can be incident on the light extraction surface 10 at a smaller incident angle.

[0010] That is, in the Figure 15 configuration, the ultraviolet rays emitted from the light-emitting tube 3 and incident on the tapered surfaces (11b, 12b) are extracted from the light extraction surface 10 to the outside of the box 2. However, as described above, since the ultraviolet rays are emitted from the light-emitting tube 3 in all directions, there are also ultraviolet rays having a component traveling in the tube axis direction (X direction) of the light-emitting tube 3. Therefore, the present inventor noticed that there is room for further improving the extraction efficiency of ultraviolet rays in the conventional ultraviolet irradiation device.

[0011] In view of the above circumstances, an object of the present invention is to provide an ultraviolet irradiation device with high extraction efficiency of ultraviolet rays.

[0012] The ultraviolet irradiation device of the present invention is characterized by comprising:

[0013] A box;

[0014] A light extraction surface provided on a side surface of the box;

[0015] An excimer lamp having a straight tubular light-emitting tube housed in the box, and a first electrode and a second electrode that are arranged separately from each other in a first direction parallel to the tube axis of the light-emitting tube and apply a voltage to the light-emitting tube; and

[0016] A reflection member having a first reflection surface facing the central portion side of the light-emitting tube and reflecting ultraviolet rays having a component traveling in the first direction, and the reflection member reflects at least a part of the ultraviolet rays emitted from the excimer lamp,

[0017] The first reflection surface of the reflection member is arranged between a first reference point and a second reference point in the first direction, the first reference point is near the first end on the first electrode side of the light-emitting tube, and the second reference point is near the second end on the side opposite to the first end.

[0018] Here, "near" means a position that is separated from the end portion (the first end or the second end) of the light-emitting tube toward the outside by a specified distance in the first direction. In addition, the specified distance is a distance equivalent to half of the separation distance between the end portion and the electrode on the side close to the end portion in the first direction.

[0019] As described above, the ultraviolet rays emitted from the excimer lamp include ultraviolet rays that do not directly travel to the light extraction surface provided on the box body. Specifically, ultraviolet rays having a component traveling in the first direction from the light-emitting tube can be cited. The ultraviolet rays traveling in the first direction from the light-emitting tube are highly likely to reach the inner wall surface of the box body rather than the light extraction surface side. The ultraviolet rays that reach the inner wall surface of the box body in this way are absorbed by the inner wall surface of the box body, and thus hardly extracted from the light extraction surface.

[0020] In contrast, according to the above configuration, the ultraviolet rays emitted from the excimer lamp and having a component traveling in the first direction are reflected by the first reflecting surface. The ultraviolet rays reflected by the first reflecting surface are reflected toward the central portion side of the light-emitting tube in the first direction. That is, by using the reflecting member to change the traveling direction of the ultraviolet rays incident on the reflecting surface, at least a part of the ultraviolet rays traveling toward the inner wall surface of the box body is reflected toward the light extraction surface side, and the ultraviolet rays extracted from the light extraction surface increase. As a result, the extraction efficiency of the ultraviolet rays of the ultraviolet ray irradiation device is improved.

[0021] In addition, by arranging the first reflecting surface between the first reference point and the second reference point, more ultraviolet rays can be reflected compared to the case where the first reflecting surface is located at a position far from the light-emitting tube.

[0022] Alternatively, the first reflecting surface may be arranged between the first electrode and the first reference point, or between the second electrode and the second reference point.

[0023] As described above, in the excimer lamp, ultraviolet rays are generated by applying a voltage to a pair of electrodes. More specifically, due to the application of this voltage, a discharge plasma is generated in the light-emitting tube, and the atoms or molecules of the light-emitting gas are excited to become an excimer state, and ultraviolet rays are emitted when they return to the ground state. Since the discharge plasma is generated between the first electrode and the second electrode, ultraviolet rays are mainly generated in the space in the light-emitting tube sandwiched by the pair of electrodes. Therefore, in order to reflect the ultraviolet rays emitted from the central portion of the light-emitting tube, particularly the space sandwiched by the pair of electrodes, as described above, the first reflecting surface is preferably arranged on the side opposite to the central portion of the light-emitting tube with respect to the pair of electrodes.

[0024] Alternatively, the reflecting member may have a plurality of the first reflecting surfaces, and the plurality of the first reflecting surfaces face each other in the first direction.

[0025] The ultraviolet rays having a component traveling in the first direction include ultraviolet rays traveling toward the first end side of the light-emitting tube and ultraviolet rays traveling toward the second end side opposite thereto. According to the above configuration, more ultraviolet rays can be extracted by reflecting both ultraviolet rays.

[0026] Alternatively, the first reflecting surface may be inclined with respect to the light extraction surface, and the ultraviolet light incident on the first reflecting surface is reflected toward the light extraction surface side.

[0027] Generally, not all of the ultraviolet light incident on the reflecting surface is reflected, but a large amount is absorbed by the reflecting surface. In view of this, the ultraviolet light irradiation device is preferably configured such that the ultraviolet light emitted from the excimer lamp and traveling in a direction different from the light extraction surface reaches the light extraction surface with a smaller number of reflections. In contrast, by inclining the first reflecting surface with respect to the light extraction surface, the ultraviolet light incident on the first reflecting surface is reflected toward the light extraction surface side. Therefore, with respect to the above configuration, it is more preferable that the ultraviolet light reflected by the first reflecting surface easily reaches the light extraction surface.

[0028] The reflecting member may also include a second reflecting surface that faces the central portion side of the light emitting tube and reflects ultraviolet light having a component traveling in a second direction orthogonal to the first direction in a plane parallel to the light extraction surface.

[0029] As described above, ultraviolet light is emitted from the light emitting tube in all directions. According to the above configuration, a part of the ultraviolet light having a component traveling in the second direction is reflected by the second reflecting surface, and the traveling direction of the ultraviolet light is changed. As a result, at least a part of the ultraviolet light traveling toward the inner wall surface of the box body, for example, is reflected toward the light extraction surface side. Thereby, the ultraviolet light extracted from the light extraction surface increases, and the extraction efficiency of the ultraviolet light is improved.

[0030] Alternatively, the reflecting member may have a plurality of the second reflecting surfaces, and the plurality of the second reflecting surfaces face each other in the second direction.

[0031] Alternatively, the second reflecting surface may be inclined with respect to the light extraction surface, and the ultraviolet light incident on the second reflecting surface is reflected toward the light extraction surface side.

[0032] Alternatively, the first reflecting surface may be located between the light emitting tube and the light extraction surface in a third direction orthogonal to the light extraction surface.

[0033] From the viewpoint of suppressing the absorption of ultraviolet light incident on the inner wall of the box body or the like at the position between the excimer lamp and the light extraction surface in the third direction, it is preferable that the first reflecting surface is arranged at the position of the above configuration. The same applies to the second reflecting surface.

[0034] The reflecting member may also include the first reflecting surface, and when viewed in the first direction, the first reflecting surface is located at a position deviated from the light emitting tube in a second direction orthogonal to the first direction in a plane parallel to the light extraction surface.

[0035] Ultraviolet rays emitted from the light-emitting tube in a state where the angle with respect to the light extraction surface is small are likely to be directed toward the inner wall of the box body and are difficult to be extracted from the box body. In contrast, according to the above configuration, at a position where the light-emitting tube deviates in the second direction when viewed in the first direction, it is possible to reflect ultraviolet rays that have a component traveling in the first direction and are traveling in a state where the angle with respect to the light extraction surface is small. As a result, the ultraviolet rays reflected toward the light extraction surface increase, and more ultraviolet rays are extracted from the light extraction surface.

[0036] The reflection member may also be made of an insulating material.

[0037] As described above, a high-frequency high voltage is applied to the electrode. Therefore, in the case where the reflection member exhibits conductivity, there is a concern that an undesired discharge path is formed between the reflection member and the electrode. In addition, there is a concern that when the position of the reflection member is displaced due to an impact such as movement, the two come into contact and short-circuit. In view of these concerns, the reflection member is preferably made of an insulating material.

[0038] The reflection member may also be made of polytetrafluoroethylene.

[0039] Polytetrafluoroethylene (PTFE) has the characteristic of being easy to process such as cutting, and the reflection member can be formed in any shape. In addition, from the viewpoint of exhibiting insulation, PTFE is also a suitable material for the reflection member.

[0040] Advantages of the Invention

[0041] According to the present invention, there is provided an ultraviolet irradiation device with high ultraviolet extraction efficiency. Description of the Drawings

[0042] Figure 1 It is a perspective view schematically showing the appearance of an embodiment of the ultraviolet irradiation device.

[0043] Figure 2A It is from Figure 1 A perspective view of the main body housing part and the cover part of the box body of the ultraviolet irradiation device disassembled.

[0044] Figure 2B It is from Figure 2A A perspective view of the reflection member disassembled from the main body housing part.

[0045] Figure 3 It is a perspective view schematically showing the structure of the electrode block.

[0046] Figure 4 It is a top view schematically showing the structure of the reflection member when viewed from the +Z direction.

[0047] Figure 5A It is a cross-sectional view schematically showing the arrangement of the reflection member in the box body when viewed along the Y direction.

[0048] Figure 5B is a cross-sectional view schematically showing the arrangement of the reflection components inside the box when viewed in the X direction.

[0049] Figure 6 is a top view showing another configuration example of the reflection component.

[0050] Figure 7 is a perspective view schematically showing the appearance of the ultraviolet irradiation device of the second embodiment.

[0051] Figure 8 is from Figure 7 a perspective view of the main body housing part and the cover part of the box of the ultraviolet irradiation device disassembled.

[0052] Figure 9 is a perspective view schematically showing the structure of the electrode block, the light-emitting tube, and the reflection component included in the ultraviolet irradiation device.

[0053] Figure 10 is disassembled Figure 9 a perspective view of the electrode block and the reflection component 4.

[0054] Figure 11 is a cross-sectional view schematically showing the arrangement of the reflection components inside the box when viewed in the Z direction.

[0055] Figure 12 is a cross-sectional view schematically showing the arrangement of the reflection components inside the box when viewed in the Y direction.

[0056] Figure 13 is a perspective view showing another configuration example of the reflection component of the second embodiment.

[0057] Figure 14A is a cross-sectional view showing yet another configuration example of the reflection component of the second embodiment.

[0058] Figure 14B is a perspective view of the ultraviolet irradiation device showing another configuration example of the reflection component.

[0059] Figure 15 is a perspective view schematically showing the structure of the ultraviolet irradiation device 100 of Patent Document 1. Detailed Embodiments

[0060] [First Embodiment]

[0061] The first embodiment of the ultraviolet irradiation device of the present invention will be described with appropriate reference to the accompanying drawings. In addition, the following drawings are schematically illustrated, and the dimensional ratios on the drawings are not necessarily the same as the actual dimensional ratios. Also, the dimensional ratios are not necessarily the same between the respective drawings.

[0062] In the following figures, Figure 15 Similarly, an X - Y - Z coordinate system will be described with the tube axis direction of the excimer lamp's light - emitting tube 3 as the X - direction and the plane orthogonal to the X - direction as the YZ - plane. More specifically, the direction orthogonal to the X - direction in the plane parallel to the light extraction surface 10 is set as the Y - direction, and the direction orthogonal to both the X - direction and the Y - direction is set as the Z - direction. The X - direction corresponds to the "first direction", the Y - direction corresponds to the "second direction", and the Z - direction corresponds to the "third direction".

[0063] In addition, in the following description, when distinguishing the positive and negative directions of the orientation, positive and negative signs are marked as in "+X direction" and "-X direction". When expressing the direction without distinguishing the positive and negative directions, it is only recorded as "X direction". That is, in this specification, when only recorded as "X direction", it includes both "+X direction" and "-X direction". The same applies to the Y - direction and the Z - direction.

[0064] In addition, in the following figures, for elements identical to those Figure 15 described above, the same reference numerals are marked, and the description is appropriately simplified.

[0065] Figure 1 is a perspective view schematically showing the appearance of an embodiment of the ultraviolet irradiation device of the present invention. In addition, Figure 2A is Figure 1 a perspective view of the main body housing part 2a and the cover part 2b of the housing 2 of the ultraviolet irradiation device 1 after disassembly. Figure 2B is a perspective view of the reflection member 4 disassembled from the Figure 2A main body housing part 2a described later.

[0066] As Figure 1 shown, the ultraviolet irradiation device 1 includes a housing 2 having a light extraction surface 10 formed on the side. In addition, as Figure 2A and Figure 2B shown, the housing 2 includes a main body housing part 2a and a cover part 2b, and houses the light - emitting tube 3 of the excimer lamp, electrode blocks (11, 12), and the reflection member 4. In Figure 2A and Figure 2B , for the sake of easy understanding, a shadow formed by a solid line is applied to the light - emitting tube 3.

[0067] The light-emitting tube 3 of the excimer lamp in the present embodiment is formed of a dielectric such as quartz glass, and a light-emitting gas containing krypton gas and chlorine gas is enclosed in the light-emitting tube 3. In the present embodiment, the light-emitting tube 3 has a straight tubular shape. As an example, in the present embodiment, the total length of the light-emitting tube 3 in the X direction is 70 mm. In addition, the number of light-emitting tubes 3 housed in the box 2 is not limited in the present invention.

[0068] The electrode block 11 and the electrode block 12 are arranged separately from each other in the X direction, and constitute electrodes for supplying power to each light-emitting tube 3. Figure 3 It is a perspective view schematically showing the structure of the electrode blocks (11, 12). As Figure 3 shown, the electrode block 11 is configured to have a placement area 11a for placing the light-emitting tube 3 of the excimer lamp (also refer to Figure 2B ), and a conical surface 11b formed at a position separated from the light-emitting tube 3 in the Y direction and inclined with respect to the XY plane. Similarly, the electrode block 12 has a placement area 12a and a conical surface 12b. Regarding the effects of the conical surfaces (11b, 12b), refer to Figure 5B the description below. In the present embodiment, the electrode block 11 corresponds to the "first electrode", and the electrode block 12 corresponds to the "second electrode".

[0069] The electrode blocks (11, 12) are made of a conductive material, and preferably made of a material that is reflective to the ultraviolet ray L1. As an example, the electrode blocks (11, 12) are both made of a metal material such as aluminum, aluminum alloy, or stainless steel.

[0070] As an example, in the present embodiment, the separation distance between the electrode blocks (11, 12) is 6 mm.

[0071] By applying a high-frequency high voltage to the electrode blocks (11, 12), the ultraviolet ray L1 is obtained from the light-emitting tube 3. In order to extract the ultraviolet ray L1 emitted in the light-emitting tube 3 to the outside of the box 2, the light extraction surface 10 is made of a glass material such as quartz glass. In addition, the light extraction surface 10 may also be composed of an opening.

[0072] As described above, the light-emitting tube 3 contains krypton gas and chlorine gas as the light-emitting gas. Therefore, the ultraviolet ray L1 whose main emission wavelength belongs to the range of 200 nm to 240 nm is obtained from the light-emitting tube 3. Here, the "main emission wavelength" refers to a wavelength band that shows a light intensity of 40% or more with respect to the highest light intensity (peak intensity) in the emission spectrum.

[0073] The absorption coefficient of proteins belonging to ultraviolet rays in the wavelength range of 200 nm to 240 nm is high, and most of them are absorbed by the surface of human skin (for example, the stratum corneum). Therefore, the ultraviolet rays belonging to the above wavelength range have the characteristics of being difficult to penetrate into the skin and having extremely low influence on the human body.

[0074] In addition, even in an excimer lamp that emits ultraviolet light with a main emission wavelength in the range of 200 nm to 240 nm, a very small amount of ultraviolet light in a wavelength band (wavelength 240 nm to 300 nm) that may affect the human body can also be emitted. In view of this, in the present embodiment, an optical filter 21 that suppresses the transmission of ultraviolet light in the wavelength range of 240 nm to 300 nm is disposed on the light extraction surface 10 (refer to Figure 2A ).

[0075] Here, "the optical filter is disposed on the light extraction surface" includes not only the case where the optical filter is integrally disposed with the light extraction surface, but also the case where the optical filter is disposed at a position separated from the light extraction surface by several millimeters to about a dozen millimeters in the Z direction. In addition, "suppressing transmission" means reducing the ratio of the light intensity of ultraviolet light in the wavelength range of 240 to 300 nm among the ultraviolet light that has passed through the optical filter to the light intensity of ultraviolet light in the wavelength range of 200 nm to 240 nm. As an example, the optical filter 21 is composed of a dielectric multilayer film in which a thin film layer of silicon dioxide (SiO2) and a thin film layer of hafnium dioxide (HfO2) are laminated.

[0076] The reflection member 4 is made of, for example, polytetrafluoroethylene (PTFE), and has reflection surfaces (4x, 4y) that are reflective to the ultraviolet light L1. The reflection member 4 is disposed on the +Z side of the main body housing portion 2a (refer to Figure 2B ).

[0077] Figure 4 is a top view schematically showing the structure of the reflection member 4 when viewed from the +Z direction. As Figure 4 shown, the reflection member 4 has two reflection surfaces 4x that are opposed to each other in the X direction and two reflection surfaces 4y that are opposed to each other in the Y direction. In the present embodiment, the reflection surface 4x corresponds to the "first reflection surface", and the reflection surface 4y corresponds to the "second reflection surface".

[0078] Figure 5A And Figure 5B is a cross-sectional view schematically showing the arrangement of the reflection member 4 in the box body 2. Figure 5A is a view when observed in the Y direction, Figure 5B is a view when observed in the X direction. As Figure 5A and Figure 5B shown, the reflection surfaces (4x, 4y) are disposed between the light emitting tube 3 and the light extraction surface 10 in the Z direction, facing the central portion side of the light emitting tube 3. In addition, in the present embodiment, the reflection surfaces (4x, 4y) are inclined with respect to the light extraction surface 10. The reflection member 4 is clamped by the main body housing portion 2a and the electrode blocks (11, 12), and the reflection surfaces (4x, 4y) are in contact with the electrode blocks (11, 12) (also refer to Figure 2A ).

[0079] More specifically, the reflecting surface 4x abuts against the electrode blocks (11, 12) and the light-emitting diode 3 (see Figure 5A ). On the other hand, in the present embodiment, the reflecting surface 4y abuts against the electrode blocks (11, 12), but the reflecting surface 4y may also abut against the electrode blocks (11, 12) and the light-emitting diode 3 (see Figure 5B ). In addition, in the present invention, the setting method of the reflecting member 4 is not limited, and whether the reflecting surfaces (4x, 4y) abut against the electrode blocks (11, 12) or the light-emitting diode 3 is arbitrary.

[0080] In addition, the reflecting surface 4x is located between the first reference point P1 and the second reference point P2 in the X direction (see Figure 5A ). The first reference point P1 is an imaginary point located at a position separated from the first end 5a on the -X side of the light-emitting diode 3 by a distance d1 in the -X direction. The distance d1 is equivalent to half of the separation distance d2 between the first end 5a and the electrode block 11. In addition, the second reference point P2 is an imaginary point located at a position separated from the second end 5b on the +X side of the light-emitting diode 3 by a distance d3 in the +X direction. The distance d3 is equivalent to half of the separation distance d4 between the second end 5b and the electrode block 12.

[0081] In addition, as an example, in the present embodiment, both the separation distance d2 and the separation distance d4 are set to 17 mm. In addition, the separation distance d2 and the separation distance d4 may be different.

[0082] In the present embodiment, the reflecting surface 4x on the -X side is located between the first end 5a and the electrode block 11 in the X direction, and the reflecting surface 4x on the +X side is located between the second end 5b and the electrode block 12 in the X direction. As described above, the ultraviolet ray L1 is mainly generated between the pair of electrode blocks (11, 12). Therefore, taking the -X side as an example, it is preferable that the reflecting surface 4x is disposed between the first end 5a and the electrode block 11.

[0083] The reflecting member 4 is constituted by, for example, a sheet-like member. Referring to Figure 4 , an example of the manufacturing sequence of the reflecting member 4 will be described. First, a sheet material having a substantially rectangular shape made of a material that is reflective to the ultraviolet ray L1 is prepared. Then, by processing such as cutting, a region 31 typically having a rectangular shape is cut out from the central portion of the sheet material to obtain a sheet material in a frame shape. Next, the cut portion 30 is formed. Then, by bending the region corresponding to the reflecting surfaces (4x, 4y) toward the -Z side, the reflecting member 4 can be constituted.

[0084] As described above, the reflection member 4 may be formed of a sheet containing fine particles of a fluororesin material such as polytetrafluoroethylene (PTFE). In particular, PTFE is easy to process such as cutting and bending, and is preferred. In addition, the reflection member 4 may also be formed by forming a reflection film that reflects the ultraviolet ray L1 on an arbitrary sheet. This reflection film is, for example, a coating film of the above-mentioned fluororesin material. In this case, the reflection film forms the reflection surfaces (4x, 4y).

[0085] In addition, PTFE exhibits diffuse reflectivity with respect to the ultraviolet ray L1. It is considered that at least a part of the diffused light reflected by the reflection surfaces (4x, 4y) showing diffuse reflectivity travels toward the light extraction surface 10, and therefore an improvement in the extraction efficiency of the ultraviolet ray L1 from the light extraction surface 10 can be expected. That is, by the reflection surfaces (4x, 4y) showing diffuse reflectivity, even if the alignment of the reflection surfaces (4x, 4y) with respect to the light extraction surface 10 or the light-emitting diode 3 is slightly deviated, the extraction efficiency of the ultraviolet ray L1 from the light extraction surface 10 is good. In other words, by the reflection surfaces (4x, 4y) showing diffuse reflectivity, an effect that the alignment of the reflection surfaces (4x, 4y) with respect to the light extraction surface 10 or the light-emitting diode 3 becomes easy can be obtained.

[0086] From the viewpoint of diffusely reflecting the ultraviolet ray L1 on the reflection surfaces (4x, 4y), the reflection member 4 may be formed of a silicone resin, or may have a ceramic film containing silica, alumina, etc. as a reflection film. In addition, the reflection surfaces showing diffuse reflectivity may also be formed by subjecting the reflection surfaces (4y, 4z) to uneven processing.

[0087] In addition, the reflection surfaces (4x, 4y) may also perform specular reflection on the ultraviolet ray L1. As an example, the reflection member 4 may also be formed of a sheet containing a metal such as aluminum, for example. However, from the viewpoint of suppressing the formation of a discharge path between the electrode blocks (11, 12) and the reflection member, the reflection member 4 preferably has insulation. From this viewpoint, for example, dielectric films having different refractive indexes may be alternately laminated on an arbitrary insulating sheet to form a dielectric multilayer film that reflects the ultraviolet ray L1. In this case, this dielectric multilayer film forms the reflection surfaces (4x, 4y).

[0088] Hereinafter, with reference to Figure 5A and Figure 5B , the traveling mode of the ultraviolet ray emitted from the light-emitting diode 3 will be described.

[0089] By disposing the reflection surface 4x between the first reference point P1 and the second reference point P2, the ultraviolet ray L1 having a component traveling in the X direction and not directly traveling to the light extraction surface 10 is reflected by the reflection surface 4x (refer to Figure 5A)。As a result, the amount of ultraviolet light L1 traveling toward the light extraction surface 10 increases, and the extraction efficiency of the ultraviolet light L1 from the light extraction surface 10 is improved. Additionally, from the perspective of reflecting the ultraviolet light L1 traveling in the +X direction and the -X direction respectively, as Figure 5A shown, it is preferable that the plurality of reflecting surfaces 4x are arranged opposite to each other.

[0090] Furthermore, by tilting the reflecting surface 4x with respect to the light extraction surface 10, among the ultraviolet light L1 reflected by the reflecting surface 4x, the amount of ultraviolet light L1 traveling toward the light extraction surface 10 can be increased. In addition, when the optical filter 21 is composed of a dielectric multilayer film, an incident angle dependence showing a decrease in the transmittance of ultraviolet light when the incident angle becomes larger is shown. Therefore, from the perspective of reducing the incident angle of ultraviolet light with respect to the optical filter 21, it is preferable that the reflecting surface 4x is tilted with respect to the light extraction surface 10.

[0091] In addition, by arranging the reflecting surface 4x in the Z direction between the light-emitting tube 3 and the light extraction surface 10, it is possible to reflect the ultraviolet light L1 traveling toward the inner wall of the housing 2 by the reflecting surface 4x at a position on the +Z side with respect to the light-emitting tube 3.

[0092] As Figure 5B shown, the ultraviolet light L1 having a component traveling in the Y direction is reflected by the reflecting surface 4y. As a result, the extraction efficiency of the ultraviolet light L1 from the light extraction surface 10 is improved. Regarding the points of arranging the plurality of reflecting surfaces 4y opposite to each other, tilting with respect to the light extraction surface 10, and arranging on the +Z side with respect to the light-emitting tube 3, the same discussion as that described for the reflecting surface 4x can be made.

[0093] As described above, the electrode blocks (11, 12) have tapered surfaces (11b, 12b) that are tilted with respect to the light extraction surface 10. As Figure 5B shown, the electrode block 11 has a tapered surface 11b, and thus the ultraviolet light L2 emitted from the light-emitting tube 3 and incident on the tapered surface 11b is reflected toward the light extraction surface 10. The same discussion can be made for the tapered surface 12b of the electrode block 12. In this case, the tapered surfaces (11b, 12b) constitute the reflecting surface 4y, and the electrode blocks (11, 12) also serve as the reflecting member 4.

[0094] [Verification]

[0095] In the ultraviolet irradiation device 1 configured as described above, verification of the irradiance of the ultraviolet light L1 extracted from the housing 2 was performed, and thus it will be described below.

[0096] (Example 1)

[0097] In this verification, the configuration of the above first embodiment was adopted as Example 1.

[0098] The irradiance of the ultraviolet ray L1 was measured using an illuminometer composed of a UV integrated light quantity meter (UIT-250) manufactured by Ushio Denki Co., Ltd. and a separate photoreceptor (VUV-S172) manufactured by Ushio Denki Co., Ltd. that had been calibrated with light of a wavelength of 222 nm. In addition, the measurement position of the irradiance was at a position 50 mm away from the light extraction surface 10 toward the +Z side.

[0099] (Comparative Example 1)

[0100] As Comparative Example 1, the irradiance of the ultraviolet ray L1 was verified in the case where the reflection member 4 was not arranged.

[0101] The conditions of Comparative Example 1 were the same as those of Example 1 except that the reflection member 4 was removed from the inside of the box body 2.

[0102] [Verification Results]

[0103] The comparison results of the irradiance obtained in this verification are shown in Table 1 below. In Table 1, the relative values of the irradiance based on Comparative Example 1 are shown.

[0104] [Table 1]

[0105] Relative value of irradiance Example 1 1.24 Comparative Example 1 1

[0106] As shown in Table 1, by arranging the reflection member 4 (Example 1), the irradiance of the ultraviolet ray taken out from the light extraction surface 10 becomes about 1.2 times that in the case where there is no reflection member 4 (Comparative Example 1).

[0107] [Consideration]

[0108] It is considered that the reason for the above results is that the reflection member 4 is arranged, and the ultraviolet ray L1 is reflected by the reflection surfaces (4x, 4y). As a result, the ultraviolet ray L1 traveling toward the light extraction surface 10 increases. That is, it can be understood that by arranging the reflection member 4, the extraction efficiency of the ultraviolet ray L1 from the light extraction surface 10 is improved.

[0109] That is, according to the configuration of the above first embodiment, an ultraviolet irradiation device with high ultraviolet extraction efficiency can be realized.

[0110] In addition, in the above first embodiment, the reflection surfaces (4x, 4y) are inclined with respect to the light extraction surface 10. However, the present invention is not limited to this, and the reflection surfaces (4x, 4y) may also be arranged perpendicular to the light extraction surface 10. Even when the reflection surfaces (4x, 4y) are not inclined with respect to the light extraction surface 10, since the ultraviolet ray L1 is reflected by the reflection surfaces (4x, 4y), for example, the ratio of the ultraviolet ray absorbed by the inner wall of the box body 2 or the like to the ultraviolet ray emitted from the light emitting tube 3 decreases. Therefore, it can be understood that the extraction efficiency of the ultraviolet ray from the light extraction surface 10 is improved.

[0111] In the above description, the reflective member 4 has a plurality of reflective surfaces 4x, but the reflective surface 4x may be one. It is presumed that even if the reflective surface 4x is disposed only on the +X side of the light emitting tube 3, the ultraviolet light L1 is reflected by the reflective surface 4x, and the amount of ultraviolet light traveling toward the light extraction surface 10 increases, resulting in an increase in the ultraviolet light extraction efficiency of the ultraviolet irradiation device.

[0112] Likewise, the number of reflective surfaces 4y may be one.

[0113] In addition, whether or not the reflecting member 4 includes the reflecting surface 4 y is arbitrary.

[0114] Furthermore, in the above description, the case where the reflecting surfaces (4x, 4y) are composed of the integral reflecting member 4 in a frame shape is described. Figure 6 As shown, the reflecting surfaces (4x, 4y) may also be composed of a plurality of separate sheet members. Figure 6 1 is a plan view showing another configuration example of the reflective member 4. Based on the above verification results, it is estimated that even when the reflective member 4 is composed of a plurality of separate members, the efficiency of extracting ultraviolet rays can be improved.

[0115] At the time of filing this application, ACGIH (American Conference of GovernmentalIndustrial Hygienists: American Industrial Hygienists Conference) and other organizations have set recommended permissible limits (TLV: Threshold Limit Value) for the amount of ultraviolet radiation to the human body per day (8 hours). However, recently, as the effects of ultraviolet radiation on the human body have become more apparent, the TLV is being relaxed for ultraviolet radiation in the wavelength range of 200nm to 240nm, which has a low impact on the human body.

[0116] Since the TLV is relaxed, it is assumed that higher-output ultraviolet irradiation is performed, and therefore it is considered that with the relaxation of the TLV, a higher-output ultraviolet irradiation device is required. In contrast, in the first embodiment, ultraviolet rays belonging to the wavelength range of 200nm to 240nm and having a low impact on the human body are emitted, and the efficiency of extracting ultraviolet rays from the housing 2 is improved. That is, according to the configuration described with reference to the first embodiment, it is also possible to cope with the demand for higher output of ultraviolet irradiation devices accompanying the relaxation of the TLV.

[0117] [Second Embodiment]

[0118] Below, refer to Figures 7 - 10 , the second embodiment of the ultraviolet irradiation device of the present invention will be described mainly focusing on the parts that are different from the first embodiment.

[0119] Figure 7 This is a perspective view schematically showing the appearance of the ultraviolet irradiation device 1 according to the second embodiment. Figure 8 is from Figure 7 A perspective view of the main housing portion 2a and the lid portion 2b of the housing 2 of the ultraviolet irradiation device 1 disassembled. In addition, Figure 9 is a perspective view schematically showing the structure of the electrode blocks (11, 12), the light-emitting tubes 3, and the reflection member 4 provided in the ultraviolet irradiation device 1. Figure 10 is to Figure 9 A perspective view of the electrode blocks (11, 12) and the reflection member 4 disassembled.

[0120] As Figure 9 and Figure 10 shown, the ultraviolet irradiation device of the present embodiment is configured such that the components are arranged in the order of the reflection member 4, the electrode blocks (11, 12), and the light-emitting tubes 3 of the excimer lamp with respect to the main housing portion 2a. In the present embodiment, one light-emitting tube 3 of the excimer lamp is housed in the housing 2. In addition, different from the first embodiment, conical surfaces (11b, 12b) are not formed on the electrode blocks (11, 12).

[0121] Figure 11 and Figure 12 are cross-sectional views schematically showing the arrangement of the reflection member 4 in the housing 2. Figure 11 is a view when observed in the Y direction. Figure 12 is a view when observed in the X direction. As Figure 11 shown, the reflection member 4 is composed of a single member having a U-shaped cross-section when observed in the Y direction. Therefore, the reflection member 4 has reflection surfaces 4x facing the central portion side of the light-emitting tube 3 and opposing each other in the X direction, and a reflection surface 4z located on the -Z side of the light-emitting tube 3.

[0122] As described above, since the ultraviolet ray L1 is generated between the electrode blocks (11, 12), it is preferable to arrange the reflection surface 4x close to the electrode blocks (11, 12). However, when taking the -X side as an example for explanation, the first end 5a of the light-emitting tube 3 is located at a position closer to the -X side than the electrode block 11, and a part of the light-emitting tube 3 is arranged to protrude from the electrode block 11 toward the -X side. Therefore, for example, when the reflection surface 4x is rectangular, it is difficult to bring the reflection surface 4x close to the electrode block 11. In view of this, in the present embodiment, as Figure 12As shown, the reflection member 4 has a notch portion 32 that avoids interference with the light-emitting tube 3. Specifically, the reflection surface 4x is U-shaped when viewed in the X direction and is disposed at a position deviated from the light-emitting tube 3 in the Y direction. Thereby, interference between the light-emitting tube 3 and the arrangement of the reflection surface 4x can be prevented, and the reflection surface 4x can be disposed close to the electrode block 11 between the first end 5a and the electrode block 11. The same applies to the reflection surface 4x on the +X side. In addition, in the above description, the reflection surface 4x is U-shaped, but the notch portion 32 may be a hole for inserting the light-emitting tube 3, and the reflection surface 4x may be O-shaped.

[0123] The reflection member 4 is the same as that referred to Figure 4 above, and can be formed, for example, by processing a sheet-like member made of PTFE. By processing the sheet-like member, as described above, a shape that matches the arrangement of the light-emitting tube 3 and the electrode blocks (11, 12) can be easily formed.

[0124] As Figure 11 shown, the reflection surface 4x reflects the ultraviolet ray L1 having a component traveling in the X direction. Thereby, the ultraviolet ray L1 traveling toward the light extraction surface 10 side increases, and the extraction efficiency of the ultraviolet ray L1 from the light extraction surface 10 is improved.

[0125] In addition, as described above, the reflection surface 4x is arranged to include a position deviated from the light-emitting tube 3 in the Y direction when viewed in the X direction. Therefore, as Figure 11 and Figure 12 shown, the reflection surface 4x has a component traveling in the X direction and can reflect the ultraviolet ray La1 traveling in a state with a small angle with respect to the XY plane. Thus, according to the present embodiment, the ultraviolet ray La1 can be reflected even at a position deviated from the light-emitting tube 3 in the Y direction when viewed in the X direction.

[0126] In addition, the reflection surface 4z reflects the ultraviolet ray Lb1 emitted from the light-emitting tube 3 and traveling toward the -Z side toward the light extraction surface 10 side (refer to Figure 11 ). Thereby, the ultraviolet ray Lb1 traveling toward the -Z side can be reflected toward the light extraction surface side.

[0127] As described above, in the ultraviolet irradiation device 1 of the second embodiment, the reflection member 4 is configured to reflect not only the ultraviolet ray L1 having a component traveling in the X direction but also the ultraviolet ray La1 having a small angle with respect to the Y direction and the ultraviolet ray Lb1 traveling toward the -Z side. Therefore, the ultraviolet rays traveling toward the light extraction surface 10 side increase, and the extraction efficiency of the ultraviolet rays from the light extraction surface 10 is further improved.

[0128] In addition, Figure 13 is a perspective view showing another configuration example of the reflection member 4 of the second embodiment. As Figure 13As shown, the reflection member 4 may also have reflection surfaces 4y that face each other in the Y direction.

[0129] Moreover, Figure 14A is a cross-sectional view showing another configuration example of the reflection member 4 of the second embodiment. As Figure 14A shown, the reflection surface 4x may be inclined with respect to the XY plane on the -Z side of the reflection surface 4x. According to this configuration, even when the ultraviolet ray L1 is reflected by the reflection surface 4x and travels toward the -Z side, the reflection surface 4z reflects the ultraviolet ray toward the light extraction surface side, which is therefore preferable.

[0130] [Modification Example]

[0131] Hereinafter, a modification example of the ultraviolet irradiation device of the present invention will be described.

[0132] 〈1〉In the above, the case where the reflection surface 4x is disposed between the first ends 5a and 5b of the light-emitting tube 3 in the X direction has been described. However, the reflection surface 4x may be disposed outside the light-emitting tube 3 between the first reference point P1 and the second reference point P2.

[0133] 〈2〉In addition, in the above, the case where the reflection member 4 is formed by processing a sheet-like member has been described. However, in the present invention, the shape of the reflection member 4 is not limited. Figure 14B is modeled after Figure 2A is a perspective view of the ultraviolet irradiation device 1 showing another configuration example of the reflection member 4. For example, as Figure 14B shown, a block material having a frame shape and a conical surface inclined with respect to the light extraction surface 10 may be disposed as the reflection member 4 in the box 2. This conical surface corresponds to the reflection surfaces (4x, 4y). The reflection member 4 can be fixed by any member such as a screw (not shown). In addition, the constituent material of the reflection member 4 is the same as that described above.

[0134] 〈3〉In the above, ultraviolet rays having a low impact on humans and a main emission wavelength in the range of 200 nm to 240 nm have been mentioned. However, a case where the ultraviolet irradiation device irradiates ultraviolet rays to an object or a space where the presence of a person is not assumed is also envisioned. That is, the wavelength of the ultraviolet rays emitted by the excimer lamp is not limited.

[0135] For example, by selecting the type of light-emitting gas enclosed in the light-emitting tube 3, the peak wavelength of the ultraviolet rays can be made different. As an example, the combinations of the light-emitting gas and the peak wavelength are KrCl (222 nm), KrBr (207 nm), XeCl (308 nm), and XeBr (283 nm).

[0136] 〈4〉In the above embodiment, the optical filter 21 is an optional component.

[0137] <5>The configuration of the above-described ultraviolet irradiation device 1 is merely an example, and the present invention is not limited to the configurations shown in the drawings.

[0138] Explanation of Reference Numerals

[0139] 1, 100: Ultraviolet irradiation device

[0140] 2: Box body

[0141] 2a: Main body housing part

[0142] 2b: Cover part

[0143] 3: Light emitting tube

[0144] 4: Reflective member

[0145] 4x, 4y, 4z: Reflective surface

[0146] 5a: First end

[0147] 5b: Second end

[0148] 10: Light extraction surface

[0149] 11, 12: Electrode block

[0150] 11a, 12a: Mounting area

[0151] 11b, 12b: Tapered surface

[0152] 21: Optical filter

[0153] 30: Cutout part

[0154] 31: Area

[0155] 32: Notch part

[0156] P1: First reference point

[0157] P2: Second reference point

Claims

1. An ultraviolet irradiation device, characterized in that, Comprising: A housing; A light extraction surface provided on a side surface of the housing; An excimer lamp having a straight tubular light-emitting tube housed in the housing, and a first electrode and a second electrode that are arranged separately from each other in a first direction parallel to the tube axis of the light-emitting tube and apply a voltage to the light-emitting tube; And A reflection member having a first reflection surface facing the central portion side of the light-emitting tube and reflecting ultraviolet rays having a component traveling in the first direction, the reflection member reflecting at least a part of the ultraviolet rays emitted by the excimer lamp, The first reflection surface of the reflection member is arranged between a first reference point and a second reference point in the first direction, the first reference point is near a first end on the first electrode side of the light-emitting tube, and the second reference point is near a second end on the side opposite to the first end.

2. The ultraviolet irradiation device according to claim 1, wherein The first reflection surface is arranged between the first electrode and the first reference point, or between the second electrode and the second reference point.

3. The ultraviolet irradiation device according to claim 1, wherein The reflection member has a plurality of the first reflection surfaces, and the plurality of the first reflection surfaces face each other in the first direction.

4. The ultraviolet irradiation device according to claim 1, wherein The first reflection surface is inclined with respect to the light extraction surface, and reflects the ultraviolet rays incident on the first reflection surface toward the light extraction surface side.

5. The ultraviolet irradiation device according to claim 1, wherein The reflection member includes a second reflection surface that faces the central portion side of the light-emitting tube and reflects ultraviolet rays having a component traveling in a second direction orthogonal to the first direction in a plane parallel to the light extraction surface.

6. The ultraviolet irradiation device according to claim 5, wherein The reflection member has a plurality of the second reflection surfaces, and the plurality of the second reflection surfaces face each other in the second direction.

7. The ultraviolet irradiation device according to claim 5, wherein The second reflection surface is inclined with respect to the light extraction surface, and reflects the ultraviolet rays incident on the second reflection surface toward the light extraction surface side.

8. The ultraviolet irradiation device according to claim 1, wherein The first reflection surface is located between the light-emitting tube and the light extraction surface in a third direction orthogonal to the light extraction surface.

9. The ultraviolet irradiation device according to claim 2, wherein The reflection member includes the first reflection surface, and when observed in the first direction, the first reflection surface is located at a position deviated from the light-emitting tube in a second direction orthogonal to the first direction in a plane parallel to the light extraction surface.

10. The ultraviolet irradiation device according to claim 1, wherein The reflection member is made of an insulating material.

11. The ultraviolet irradiation device according to claim 9, wherein The reflection member is made of polytetrafluoroethylene.

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