JP2017173167A - Ultraviolet irradiation device and ultraviolet detection method - Google Patents

Abstract

An ultraviolet irradiation device and an ultraviolet detection method capable of improving the reliability of detecting light having a wavelength of 200 nm or less.
An ultraviolet lamp that emits first light having a first peak wavelength of 200 nm or less, a light transmitting member that is irradiated with the first light from the ultraviolet lamp, and a light transmitting member. The first phosphor 16 that is excited by the first light and emits light having a wavelength exceeding 200 nm, and the first detection element 17 that detects the light emitted from the first phosphor 16 are provided. .
[Selection] Figure 2

Description

  Embodiments described herein relate generally to an ultraviolet irradiation device and an ultraviolet detection method.

  For example, a manufacturing process of a liquid crystal substrate or the like includes a light cleaning process in which ozone is generated in the air by vacuum ultraviolet rays emitted from an ultraviolet lamp, and the liquid crystal substrate or the like is cleaned using ozone. In this type of light cleaning process, an ultraviolet irradiation device having an ultraviolet lamp such as an excimer lamp that emits light having a peak wavelength of 172 nm or a low-pressure mercury lamp that emits light having peak wavelengths of 185 nm and 254 nm is used.

  In the light cleaning step, for example, the illuminance of vacuum ultraviolet rays emitted from an ultraviolet lamp is managed in order to keep the generation state of ozone properly, and the illuminance of vacuum ultraviolet rays emitted from the ultraviolet lamp is detected. As an illuminance sensor that measures illuminance, an illuminometer that detects light having a wavelength longer than 200 nm is widespread. However, when detecting vacuum ultraviolet rays having a wavelength of 200 nm or less, an illuminance meter dedicated to vacuum ultraviolet rays is used.

JP 2004-61417 A

  When the distance from the surface of the ultraviolet lamp becomes long, the above-described illuminance meter dedicated to vacuum ultraviolet rays becomes difficult to properly detect the illuminance of vacuum ultraviolet rays. For this reason, the illuminance meter dedicated to vacuum ultraviolet rays is installed in the vicinity of the surface of the ultraviolet lamp in order to properly detect the illuminance of vacuum ultraviolet rays, and tends to deteriorate early due to ozone generated by the ultraviolet lamp. is there. Therefore, when using an illuminance meter dedicated to vacuum ultraviolet rays, the reliability of detecting vacuum ultraviolet rays is poor.

  In addition, the illuminance meter dedicated to vacuum ultraviolet rays is more expensive than a general illuminance meter. Therefore, when a large number of ultraviolet lamps are used, ultraviolet rays can be irradiated by installing a vacuum ultraviolet illuminance meter for each ultraviolet lamp. The manufacturing cost of the device increases.

  Then, an object of this invention is to provide the ultraviolet irradiation device and ultraviolet detection method which can improve the reliability which detects the light whose wavelength is 200 nm or less.

  The ultraviolet irradiation device according to the embodiment includes an ultraviolet lamp that emits first light having a first peak wavelength of 200 nm or less, a light transmission member that is irradiated with the first light from the ultraviolet lamp, and the light transmission member A first phosphor that is excited by the first light and emits light having a wavelength exceeding 200 nm; and a first detection element that detects the light emitted from the first phosphor. It has.

  According to the present invention, it is possible to improve the reliability of detecting light having a wavelength of 200 nm or less.

It is sectional drawing which shows typically the ultraviolet irradiation device which concerns on 1st Embodiment. It is sectional drawing which shows typically the illumination intensity detection part which the ultraviolet irradiation device which concerns on 1st Embodiment has. It is sectional drawing which shows typically the illumination intensity detection part which the ultraviolet irradiation device which concerns on 2nd Embodiment has. It is sectional drawing which shows typically the illumination intensity detection part which the ultraviolet irradiation device which concerns on 3rd Embodiment has. It is sectional drawing which shows typically the illumination intensity detection part which the ultraviolet irradiation device concerning 4th Embodiment has. It is sectional drawing which shows typically the illumination intensity detection part which the ultraviolet irradiation device which concerns on the modification of 4th Embodiment has.

  An ultraviolet irradiation device according to an embodiment described below includes an ultraviolet lamp, a glass plate as a light transmission member, a phosphor layer as a first phosphor, and a first detection element. The ultraviolet lamp emits first light having a first peak wavelength of 200 nm or less. The glass plate is irradiated with the first light from the ultraviolet lamp. The phosphor layer is provided on the glass plate. The phosphor layer is excited by the first light and emits light having a wavelength exceeding 200 nm. The first detection element detects light emitted from the first phosphor.

  In addition, the ultraviolet lamp in the ultraviolet irradiation apparatus according to the embodiment described below emits second light having a second peak wavelength exceeding 200 nm and not more than 380 nm. The first phosphor layer as the first phosphor is excited by the second light and emits light having a longer wavelength than the second light. The first detection element detects light emitted from the first phosphor layer by the first light and the second light irradiated from the ultraviolet lamp. The ultraviolet irradiation device further includes a wavelength cut filter as an optical filter, a second detection element, and an arithmetic circuit as an arithmetic element. The wavelength cut filter is disposed between the ultraviolet lamp and the glass plate. The wavelength cut filter transmits only the second light emitted from the ultraviolet lamp. The second detection element detects light emitted from the first phosphor layer by the second light transmitted through the wavelength cut filter. The arithmetic circuit calculates a difference between the detection values detected by the first detection element and the second detection element.

  Moreover, the ultraviolet irradiation device according to the embodiment described below further includes a second phosphor layer as a second phosphor. The second phosphor layer is provided on the glass plate. The second phosphor layer is excited by light emitted from the first phosphor layer as the first phosphor, and emits light having a longer wavelength than the light emitted from the first phosphor layer. The first detection element detects light emitted from the second phosphor layer.

  Further, in the ultraviolet detection method according to the embodiment described below, the wavelength emitted from the phosphor layer by exciting the phosphor layer provided on the glass plate with light having a peak wavelength of 200 nm or less emitted from the ultraviolet lamp. Detects light exceeding 200 nm.

(First embodiment)
Hereinafter, an ultraviolet irradiation device according to an embodiment will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing an ultraviolet irradiation apparatus according to the first embodiment. FIG. 2 is a cross-sectional view schematically illustrating an illuminance detection unit included in the ultraviolet irradiation device according to the first embodiment. In FIG. 2 and subsequent figures, for the convenience of explanation, the vertical direction on the drawing is shown in the opposite direction to FIG.

(Configuration of UV irradiation device)
As shown in FIG. 1, the ultraviolet irradiation apparatus 1 according to the first embodiment includes an ultraviolet lamp 10 that irradiates an object to be irradiated W with vacuum ultraviolet rays, and vacuum ultraviolet rays that are emitted from the ultraviolet lamp 10 toward the object W to be irradiated. A reflecting plate 11 having a reflecting surface 11a to be reflected and an illuminance detecting unit 12 for detecting the illuminance of the first light emitted from the ultraviolet lamp 10 are provided.

  In the present embodiment, a configuration using a low-pressure mercury lamp as the ultraviolet lamp 10 will be described. When the low-pressure mercury lamp is used, the ultraviolet lamp 10 includes a first light having a first peak wavelength of 200 nm or less, for example, 185 nm, and a second peak wavelength exceeding 200 nm, for example, 254 nm or less. Second light is emitted. The ultraviolet lamp 10 is not limited to a low-pressure mercury lamp. For example, a xenon excimer lamp that emits light having a first peak wavelength of 172 nm may be used, and the first peak wavelength is 200 nm. The following semiconductor light emitting elements such as LED (light emitting diode) and LD (laser diode) may be used. Further, the first peak wavelength and the second peak wavelength are not limited to a single wavelength, respectively. For example, the first peak wavelength may include a plurality of peaks at 200 nm or less.

  The illuminance detection unit 12 is disposed away from the outer peripheral surface, which is the surface of the ultraviolet lamp 10, and is fixed to the reflection surface 11 a side of the reflection plate 11. The illuminance detection unit 12 may be disposed in the vicinity of the ultraviolet lamp 10 so as to receive the first and second light emitted by the ultraviolet lamp 10 and may be disposed separately from the reflector 11. .

  The irradiated object W is, for example, a liquid crystal substrate, and is placed on the stage 14 and irradiated with ultraviolet rays from the ultraviolet lamp 10, for example. The stage 14 on which the irradiated object W is placed is transported in a direction orthogonal to the central axis direction of the linear ultraviolet lamp 10 by a transport mechanism (not shown), so that the irradiated surface of the irradiated object W is irradiated. The ultraviolet rays of the ultraviolet lamp 10 are irradiated over the entire area.

(Configuration of illuminance detector)
As shown in FIG. 2, the illuminance detection unit 12 includes a glass plate 15 as a light transmitting member to which the first light and the second light of the ultraviolet lamp 10 are irradiated, and a first plate provided on the glass plate 15. A phosphor layer 16 as a phosphor and a first detection element 17 that detects the illuminance of light emitted from the phosphor layer 16 are included.

  The glass plate 15 is supported on the reflecting surface 11 a of the reflecting plate 11. In the present embodiment, the glass plate 15 is used as the light transmitting member, but a resin plate having light transmittance may be used.

The phosphor layer 16 is excited by the first light (185 nm) emitted from the ultraviolet lamp 10 and emits light having a peak wavelength of, for example, 452 nm as light having a wavelength exceeding 200 nm. The phosphor layer 16 is formed, for example, by applying BaMgAl ₁₀ O ₁₇ : Eu used as a blue phosphor on the glass plate 15. The phosphor layer 16 is provided on at least one surface of both surfaces of the glass plate 15, for example, on the surface of the glass plate 15 on the side facing the ultraviolet lamp 10.

  As shown in FIG. 1, the first detection element 17 is provided in a mounting portion 18 of the glass plate 15 that is disposed at a position facing the ultraviolet lamp 10, and is outside the reflection surface 11 a of the reflection plate 11. Are fixed through holes. The first detection element 17 receives light emitted from the phosphor layer 16 via the glass plate 15. As the first detection element 17, a general sensor that detects light having a wavelength of 200 nm or more is used. In the present embodiment, as the first detection element, a sensor suitable for detecting the peak wavelength (452 nm) of the light emitted from the phosphor layer 16, that is, the peak sensitivity wavelength of the light for detecting the illuminance is about 450 nm. Is preferably used. Moreover, the 1st detection element 17 is connected to the control circuit contained in the lighting circuit part (not shown) which controls lighting of the ultraviolet lamp 10, for example. The first detection element 17 may be a so-called illuminometer itself, or the first detection element 17 is configured to have only the function of a light receiving head, for example, and is guided from the light receiving head by an optical fiber (not shown). The light may be guided to a light receiving element (not shown). In short, any form may be adopted as long as the peak sensitivity wavelength of light detected by the first detection element 17 is about 450 nm.

  The vacuum ultraviolet rays radiated from the ultraviolet lamp 10 are attenuated in the air. Therefore, from the viewpoint of improving the detection accuracy of the first light, as shown in FIGS. 1 and 2, the distance d between the surface of the ultraviolet lamp 10 and the first detection element 17 is set as small as possible. It is preferable.

(Detection of ultraviolet rays by illuminance detector)
As shown in FIG. 2, the illuminance detection unit 12 uses the first light (185 nm) among the first light (185 nm) and the second light (254 nm) emitted from the ultraviolet lamp 10 to phosphor layer 16. Is excited, and the phosphor layer 16 emits light of 452 nm. The 452 nm light emitted from the phosphor layer 16 passes through the glass plate 15 and the illuminance is detected by the first detection element 17. As described above, the first detection element 17 of the illuminance detection unit 12 detects the illuminance of the light in which the first light (185 nm) emitted from the ultraviolet lamp 10 is converted to a wavelength exceeding 200 nm by the phosphor layer 16. To do. That is, the first detection element 17 indirectly detects the illuminance of the first light (185 nm) of the ultraviolet lamp 10 by the illuminance of the light (452 nm) emitted from the phosphor layer 16.

  In the present embodiment, the second light having a wavelength of 254 nm emitted from the ultraviolet lamp 10 is transmitted through the glass plate 15, but the second light does not excite the phosphor layer 16, and the first light It is not detected by the detection element 17. In addition, the 2nd light which permeate | transmitted the glass plate 15 may be detected using another detection element as needed. For example, the control circuit may perform calculation for correcting the illuminance of the first light detected by the first detection element 17 based on the illuminance of the second light detected by another detection element. Thereby, it is possible to increase the accuracy of the detection value of the first light.

(UV detection method)
The ultraviolet detection method using the ultraviolet irradiation device 1 configured as described above is provided on the glass plate 15 by the first light (185 nm) having a first peak wavelength of 200 nm or less emitted from the ultraviolet lamp 10. The phosphor layer 16 is excited to detect light (452 nm) emitted from the phosphor layer 16 and having a wavelength exceeding 200 nm.

  As described above, the ultraviolet irradiation device 1 according to the first embodiment includes the glass plate 15 to which the first light having the first peak wavelength of 200 nm or less is irradiated from the ultraviolet lamp 10, and the glass plate 15 provided with the first light. A phosphor layer 16 that is excited by light of 1 and emits light having a wavelength exceeding 200 nm, and a first detection element 17 that detects light irradiated from the glass plate 15. This makes it possible to dispose the first detection element 17 away from the surface of the ultraviolet lamp 10 using the popular first detection element 17 that detects light having a wavelength exceeding 200 nm. The illuminance of the first light that is 200 nm or less emitted from the ultraviolet lamp 10 can be detected through the glass plate 15 and the phosphor layer 16. For this reason, it is suppressed that the 1st detection element 17 deteriorates by ozone, and the reliability which detects the light whose wavelength is 200 nm or less can be improved.

  In addition, according to the first embodiment, it is possible to detect light having a wavelength of 200 nm or less using the general first detection element 17 that detects light having a wavelength exceeding 200 nm. The manufacturing cost of the illuminance detection unit 12 of the irradiation apparatus 1 can be suppressed.

  Hereinafter, an ultraviolet irradiation device according to another embodiment will be described with reference to the drawings. In other embodiments, the same components as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and the description thereof is omitted.

(Second Embodiment)
FIG. 3 is a cross-sectional view schematically showing an illuminance detection unit included in the ultraviolet irradiation apparatus according to the second embodiment. The second embodiment is different from the first embodiment in the configuration of the illuminance detection unit.

(Configuration of illuminance detector)
As illustrated in FIG. 3, the ultraviolet irradiation device 2 of the second embodiment includes an illuminance detection unit 22 that detects the illuminance of the first light emitted from the ultraviolet lamp 10. The illuminance detection unit 22 is disposed on the reflection surface 11 a of the reflection plate 11 in the same manner as the illuminance detection unit 12 described above. The illuminance detection unit 22 includes a glass plate 15, a first phosphor layer 25 as a first phosphor provided on the glass plate 15, and a second phosphor as a second phosphor provided on the glass plate 15. Phosphor layer 26 and first detection element 17 that detects the illuminance of light emitted from the second phosphor layer 26.

The first phosphor layer 25 is excited by the first light (185 nm) of the ultraviolet lamp, and emits light having a wavelength exceeding 200 nm, for example, light having a peak wavelength of 452 nm. The first phosphor layer 25 is formed, for example, by applying BaMgAl ₁₀ O ₁₇ : Eu used as a blue phosphor on the surface of the glass plate 15 on the ultraviolet lamp 10 side.

  The second phosphor layer 26 is excited by light (452 nm) emitted from the first phosphor layer 25, and emits light having a longer wavelength than this light, for example, light having a peak wavelength of 550 nm. The second phosphor layer 26 is formed by being applied on the surface of the glass plate 15 on the first detection element 17 side. In the second embodiment, as the first detection element 17, a general sensor having a peak sensitivity wavelength of light for detecting illuminance of about 550 nm, for example, F3UV manufactured by OMRON Corporation is used.

  In the second embodiment, the first phosphor 25 and the second phosphor layer 26 are respectively provided on both surfaces of the glass plate 15, but the first phosphor is disposed on one surface of the glass plate 15. The layer 25 and the second phosphor layer 26 may be provided in a stacked manner. In this case, the first phosphor layer 25 and the second phosphor layer 26 are arranged in this order from the ultraviolet lamp 10 side toward the first detection element 17 side.

(Detection of ultraviolet rays by illuminance detector)
As shown in FIG. 3, in the illuminance detection unit 22, the first fluorescence (185 nm) is emitted from the first light (185 nm) and the second light (254 nm) emitted from the ultraviolet lamp 10. The body layer 25 is excited, and the first phosphor layer 25 emits light of 452 nm. The 452 nm light emitted from the first phosphor layer 25 is transmitted through the glass plate 15, the second phosphor layer 26 is excited by this 425 nm light, and the second phosphor layer 26 emits 550 nm light. To emit. Illuminance of the light emitted from the second phosphor layer 26 is detected by the first detection element 17. As described above, the first detection element 17 causes the first light (185 nm) radiated from the ultraviolet lamp 10 to be 2 with a wavelength exceeding 200 nm by the first phosphor layer 25 and the second phosphor layer 26. Detect the illuminance of the light converted into stages. That is, the first detection element 17 indirectly detects the illuminance of the first light (185 nm) of the ultraviolet lamp 10 by the illuminance of the light (550 nm) emitted from the second phosphor layer 26. Also in the present embodiment, the second light having a wavelength of 254 nm emitted from the ultraviolet lamp 10 is transmitted through the glass plate 15, but the first phosphor layer 25 and the second fluorescent light are transmitted by the second light. The body layer 26 is not excited and is not detected by the first detection element 17.

  As described above, the ultraviolet irradiation device 2 according to the second embodiment uses the first detection element 17 that detects light having a wavelength exceeding 200 nm, as in the first embodiment, and uses the first detection element 17. The detection element 17 can be disposed away from the surface of the ultraviolet lamp 10 and the illuminance of the first light, which is 200 nm or less, emitted from the ultraviolet lamp 10 is changed to the glass plate 15 and the first phosphor layer. 25 and the second phosphor layer 26 can be detected. For this reason, it is suppressed that the 1st detection element 17 deteriorates by ozone, and the reliability which detects the light whose wavelength is 200 nm or less can be improved.

  In addition, according to the second embodiment, the wavelength of light detected by the first detection element 17 is converted to 550 nm as compared with the first embodiment. Since light having a wavelength of 550 nm has a high relative visibility to human eyes and a high ability to recognize light, a so-called optical sensor generally has an increased light receiving sensitivity of 550 nm. Therefore, the general first detection element 17 can be used, and the degree of freedom of selection of the first detection element 17 is increased, so that the manufacturing cost is increased particularly when a large number of ultraviolet lamps 10 are used. Can be suppressed.

(Third embodiment)
FIG. 4 is a cross-sectional view schematically showing an illuminance detection unit included in the ultraviolet irradiation apparatus according to the third embodiment. The third embodiment is different from the first embodiment in that the glass plate 15 and the phosphor layer 16 of the illuminance detection unit 12 described above are provided in the ultraviolet lamp 10.

(Configuration of illuminance detector)
As illustrated in FIG. 4, the ultraviolet irradiation device 3 according to the third embodiment includes an illuminance detection unit 32 that detects the illuminance of the first light emitted from the ultraviolet lamp 10. The illuminance detection unit 32 includes a glass plate 15 provided in the ultraviolet lamp 10, a phosphor layer 16 provided on the glass plate 15, and a first detection element 17 that detects the illuminance of light emitted from the phosphor layer 16. Have.

  In FIG. 4, a part of the glass discharge vessel constituting the ultraviolet lamp 10 also serves as the glass plate 15 and the phosphor layer 16 is provided on a part of the discharge vessel. 15 may be incorporated.

  For example, the first detection element 17 is fixed to the reflection surface 11a of the reflection plate 11 shown in FIG. Further, the first detection element 17 is preferably arranged in the mounting portion 18 hermetically sealed by another light transmission member (not shown) from the viewpoint of suppressing deterioration due to ozone.

(Detection of ultraviolet rays by illuminance detector)
Similarly to the illuminance detection unit 12 shown in FIG. 2, the illuminance detection unit 32 uses the first light (185 nm) among the first light (185 nm) and the second light (254 nm) emitted from the ultraviolet lamp 10. The phosphor layer 16 is excited, and the phosphor layer 16 emits light of 452 nm. The 452 nm light emitted from the phosphor layer 16 passes through the glass plate 15 and the illuminance is detected by the first detection element 17. As described above, the first detection element 17 of the illuminance detection unit 32 detects the illuminance of the light in which the first light (185 nm) emitted from the ultraviolet lamp 10 is converted to a wavelength exceeding 200 nm by the phosphor layer 16. To do. That is, the first detection element 17 indirectly detects the illuminance of the first light (185 nm) of the ultraviolet lamp 10 by the illuminance of the light (452 nm) emitted from the phosphor layer 16.

  As described above, the ultraviolet irradiation device 3 according to the third embodiment uses the first detection element 17 that detects light having a wavelength exceeding 200 nm, as in the first embodiment, and uses the first detection element 17. The detection element 17 can be arranged away from the surface of the ultraviolet lamp 10 and the illuminance of the first light emitted by the ultraviolet lamp 10 that is 200 nm or less can be detected via the glass plate 15. It becomes possible. For this reason, it is suppressed that the 1st detection element 17 deteriorates by ozone, and the reliability which detects the light whose wavelength is 200 nm or less can be improved.

  In addition, according to the third embodiment, only the first detection element 17 may be disposed outside the ultraviolet lamp 10, and the entire ultraviolet irradiation device 3 can be reduced in size.

  In the third embodiment, the glass plate 15 and the phosphor layer 16 of the illuminance detection unit 12 in the first embodiment are incorporated in the ultraviolet lamp 10, but the illuminance in the second embodiment described above. The glass plate 15, the first phosphor layer 25, and the second phosphor layer 26 of the detection unit 22 may be incorporated in the ultraviolet lamp 10. Also in this configuration, the same effect as that of the second embodiment can be obtained.

(Fourth embodiment)
FIG. 5 is a cross-sectional view schematically showing an illuminance detection unit included in the ultraviolet irradiation device according to the fourth embodiment. The fourth embodiment is different from the first embodiment in that the illuminance detection unit includes first and second detection elements.

(Configuration of illuminance detector)
As illustrated in FIG. 5, the ultraviolet irradiation device 4 of the fourth embodiment includes an illuminance detection unit 42 that detects the illuminance of the first light emitted from the ultraviolet lamp 10. The illuminance detection unit 42 is disposed on the reflection surface 11a of the reflection plate 11 in the same manner as the illuminance detection units 12 and 22 described above. The illuminance detection unit 42 includes a glass plate 15, a phosphor layer 33 provided on the glass plate 15, and a wavelength cut filter 34 as an optical filter that transmits only the second light emitted from the ultraviolet lamp 10. Have. The illuminance detection unit 42 includes a first detection element 35 as a first detection element that detects light emitted from the phosphor layer 33 by the first light and the second light emitted from the ultraviolet lamp 10, and The second detection element 36 that detects the light emitted from the phosphor layer 33 by the second light transmitted through the wavelength cut filter 34, the detection value E 1 detected by the first detection element 35, and the second detection element 36 And an arithmetic circuit 37 as an arithmetic element for calculating a difference ΔE from the detected value E2.

  The wavelength cut filter 34 is disposed between the ultraviolet lamp 10 and the glass plate 15. As the wavelength cut filter 34, for example, a flat plate made of ozoneless quartz is used. The wavelength cut filter 34 is disposed away from the glass plate 15, but may be provided in a partial region on the glass plate 15.

  The first detection element 35 is disposed to face a region of the glass plate 15 other than the region facing the wavelength cut filter 34. The second detection element 36 is disposed to face the wavelength cut filter 34 with the glass plate 15 interposed therebetween. As the first detection element 35 and the second detection element 36, a general sensor that detects light having a wavelength of 200 nm or more is used. In the fourth embodiment, as the first detection element 35 and the second detection element 36, it is preferable to use a sensor whose peak sensitivity wavelength of light for detecting illuminance is about 525 nm.

  Since the vacuum ultraviolet rays radiated from the ultraviolet lamp 10 are attenuated in the air, also in this embodiment, from the viewpoint of improving the detection accuracy of the first light, as shown in FIG. It is preferable to set each distance d between the detection element 35 and the second detection element 36 as small as possible. Further, the first detection element 35 and the second detection element 36 are respectively arranged at positions where the distances d between the surface of the ultraviolet lamp 10 and the first detection element 35 and the second detection element 36 are equal. Thus, the detection accuracy of the first light is enhanced.

The phosphor layer 33 is excited by the first light (185 nm) and the second light (254 nm), respectively, and emits light having a wavelength longer than that of the second light. For example, Zn ₂ SiO ₄ : Mn, which is used as a green phosphor, is applied to the phosphor layer 33 on the first detection element 35 and the second detection element 36 side of the glass plate 15. It is formed by. The phosphor layer 33 is excited by light having a wavelength of about 150 nm to about 280 nm, and emits light having a peak wavelength of 525 nm. The phosphor layer 33 may be provided on the surface of the glass plate 15 on the ultraviolet lamp 10 side.

  As the arithmetic circuit 37, for example, a control circuit included in a lighting circuit unit (not shown) that controls lighting of the ultraviolet lamp 10 may be used. The illuminance of the light emitted from the phosphor layer 33 by the first light and the second light is larger than the illuminance of the light emitted from the phosphor layer 33 only by the second light. Therefore, the illuminance detection value E1 detected by the first detection element 35 and the illuminance detection value E2 detected by the second detection element 36 satisfy E1> E2. Therefore, the arithmetic circuit 37 detects the illuminance of the first light by calculating E1−E2 = ΔE.

(Detection of ultraviolet rays by illuminance detector)
As shown in FIG. 5, in the illuminance detection unit 42, the phosphor layer 33 is excited by both the first light (185 nm) and the second light (254 nm) emitted from the ultraviolet lamp 10, and the phosphor layer 33. Emits 525 nm light. The first detection element 35 detects a detection value E1 that is illuminance of 525 nm light that is transmitted through the glass plate 15 and emitted from the phosphor layer 33 by the first light and the second light.

  On the other hand, in the illuminance detection unit 42, at the place where the wavelength cut filter 34 is disposed, the first light of the first light (185 nm) and the second light (254 nm) emitted from the ultraviolet lamp 10 has a wavelength. It is blocked by the cut filter 34 and only the second light (254 nm) passes through the wavelength cut filter 34. The second light (254 nm) transmitted through the wavelength cut filter 34 excites the phosphor layer 33, and the phosphor layer 33 emits light of 525 nm. The light having a wavelength of 525 nm transmitted through the glass plate 15 and emitted from the phosphor layer 33 only by the second light (254 nm) is detected by the second detection element 36 as a detection value E2 as illuminance.

  The arithmetic circuit 37 calculates a difference ΔE between the detection values E1 and E2 of the first detection element 35 and the second detection element 36. As a result, the illuminance detection unit 42 indirectly detects the illuminance of the first light (185 nm) of the ultraviolet lamp 10 by the difference ΔE.

  As described above, the ultraviolet irradiation device 4 according to the fourth embodiment is similar to the first to third embodiments in that the first detection element 35 and the second detection element 35 detect the light having a wavelength exceeding 200 nm. Using the detection element 36, the first detection element 35 and the second detection element 36 can be arranged apart from the surface of the ultraviolet lamp 10, and 200 nm or less emitted from the ultraviolet lamp 10. It becomes possible to detect the illuminance of one light. For this reason, it is suppressed that the 1st detection element 35 and the 2nd detection element 36 deteriorate by ozone, and the reliability which detects the light whose wavelength is 200 nm or less can be improved.

  In addition, according to the fourth embodiment, the wavelength of light detected by the first detection element 35 and the second detection element 36 is converted to a longer wavelength (525 nm) compared to the first embodiment. The Although light at 525 nm is not as light as light at 550 nm, it has a high specific vision sensitivity for human eyes and a high ability to recognize light. Therefore, a so-called photosensor with an increased light receiving sensitivity at 525 nm is also common. . Therefore, the general first detection element 35 and the second detection element 36 can be used, and the degree of freedom of selection of the first detection element 35 and the second detection element 36 is increased. In the case where a large number of ultraviolet lamps 10 are used, an increase in manufacturing cost can be suppressed.

  Although the phosphor layer 33 is formed as a single layer, the phosphor layer 33 is excited by the first light and the second light and emits light having a longer wavelength than the second light. Plural kinds of phosphor layers may be laminated.

  In the fourth embodiment, the configuration of the third embodiment may be applied. That is, as shown in FIG. 6, the illuminance detection unit 52 causes the phosphor layer 33 to be excited by both the first light (185 nm) and the second light (254 nm) emitted from the ultraviolet lamp 10. The 525 nm light emitted from the layer 33 is detected by the first detection element 35, passes through the wavelength cut filter 34, and the 525 nm light emitted from the phosphor layer 33 only by the second light (254 nm) is the second light. It may be configured to be detected by the detection element 36.

  In the first to fourth embodiments described above, the illuminance detectors 12, 22, 32, 42, and 52 that detect the illuminance of vacuum ultraviolet rays are provided. However, a light amount sensor is used instead of the illuminance sensor. The same effect as that of the present embodiment can be obtained.

  Although the embodiments of the present invention have been described, the embodiments are presented as examples and are not intended to limit the scope of the present invention. The embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. The embodiments and modifications thereof are included in the scope of the present invention and the gist thereof, and are also included in the invention described in the claims and the equivalents thereof.

1, 2, 3, 4, 5 Ultraviolet irradiation device 10 Ultraviolet lamp 11 Reflector 12, 22, 32, 42, 52 Illuminance detection unit 15 Glass plate (light transmission member)
16, 33 Phosphor layer (first phosphor)
17 1st detection element 25 1st fluorescent substance layer (1st fluorescent substance)
26 Second phosphor layer (second phosphor)
34 Wavelength cut filter (optical filter)
35 first detection element 36 second detection element 37 arithmetic circuit (arithmetic element)
W Subject to be irradiated

Claims (4)

An ultraviolet lamp that emits first light having a first peak wavelength of 200 nm or less;
A light transmissive member irradiated with the first light from the ultraviolet lamp;
A first phosphor provided on the light transmitting member and excited by the first light to emit light having a wavelength exceeding 200 nm;
A first detection element for detecting light emitted from the first phosphor;
An ultraviolet irradiation device comprising: The ultraviolet lamp emits a second light having a second peak wavelength exceeding 200 nm and not more than 380 nm,
The first phosphor is excited by the second light, emits light having a longer wavelength than the second light,
The first detection element detects light emitted from the first phosphor by the first light and the second light emitted from the ultraviolet lamp,
The ultraviolet irradiation device is
An optical filter disposed between the ultraviolet lamp and the light transmitting member and transmitting only the second light emitted from the ultraviolet lamp;
A second detection element that detects light emitted from the first phosphor by the second light transmitted through the optical filter;
An arithmetic element for calculating a difference between detection values detected by the first detection element and the second detection element;
The ultraviolet irradiation device according to claim 1, further comprising: A second phosphor that is provided on the light transmitting member and is excited by light emitted from the first phosphor and emits light having a longer wavelength than the light emitted from the first phosphor;
The first detection element detects light emitted by the second phosphor;
The ultraviolet irradiation device according to claim 1.   An ultraviolet detection method for detecting light emitted from the phosphor and having a wavelength exceeding 200 nm by exciting a phosphor provided on the light-transmitting member with light having a peak wavelength of 200 nm or less emitted from an ultraviolet lamp.

Images