Irradiation device, light-emitting device and irradiation method for ultraviolet light

Abstract

To reduce curing variance of an object.SOLUTION: An irradiation device has: an irradiation device which irradiates an object with lights, wherein the irradiation device comprises a first light source and a second light source emitting ultraviolet light having mutually different light distributions; a mounting table which has an arrangement region where the object is arranged so as to irradiate the object with the ultraviolet light; and irradiation means which irradiates the object with the ultraviolet light from the first light source before the ultraviolet light from the second light source.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an irradiation device, a light-emitting device, and an ultraviolet light irradiation method. [Background technology]

[0002] Conventionally, in order to reduce variations in curing of an object, a light irradiation module has been disclosed that includes multiple light irradiation devices, each including a first light-emitting element and a second light-emitting element, and the wavelength of the light from the second light-emitting element is shorter than the wavelength of the light from the first light-emitting element (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-090055 Summary of the Invention [Problem to be solved by the invention]

[0004] Embodiments of the present disclosure aim to reduce hardening variability in an object. [Means for solving the problem]

[0005] An irradiation device according to an embodiment of the present disclosure is an irradiation device that irradiates light onto an object, and includes a light-emitting device having a first light source and a second light source that irradiate ultraviolet light having different light distributions from each other, a mounting table having a placement area where the object is placed to be irradiated with the ultraviolet light, and irradiation means that irradiates the object with the ultraviolet light from the first light source before the ultraviolet light from the second light source.

[0006] A light emitting device according to an embodiment of the present disclosure is a light emitting device mounted on an irradiation device that irradiates light onto an object, and includes a first light source and a second light source that irradiate ultraviolet light with different light distributions, and there is at least a non-overlapping area between the area irradiated by light from the first light source and the area irradiated by light from the second light source.

[0007] An ultraviolet light irradiation method according to an embodiment of the present disclosure is a method of irradiating ultraviolet light using an irradiation device, in which the irradiation device irradiates ultraviolet light of a first emission peak wavelength having a different light distribution from each other using a first light source and a second light source, each including at least one first light-emitting element that emits ultraviolet light of the first emission peak wavelength, irradiates ultraviolet light of the first emission peak wavelength having a different light distribution from each other using a third light source and a fourth light source, each including at least one second light-emitting element that emits ultraviolet light of a second emission peak wavelength that is shorter than the first emission peak wavelength, and irradiates an object with the ultraviolet light of the first emission peak wavelength before the ultraviolet light of the second emission peak wavelength. [Effects of the Invention]

[0008] According to the embodiments of the present disclosure, it is possible to reduce variations in hardening of an object. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic side view showing the configuration of an irradiation device according to a first embodiment. [Figure 2] 1 is a schematic cross-sectional view showing a state in which a first region of an object is irradiated with both first ultraviolet light at a first light distribution angle from a first light source and second ultraviolet light at a second light distribution angle from a second light source. FIG. [Figure 3] 10 is a schematic cross-sectional view showing a state in which only second ultraviolet light from a second light source at a second luminous intensity distribution angle is irradiated onto a second region of the object. FIG. [Figure 4] 4 is a schematic cross-sectional view showing a state in which light of peak light intensity among first ultraviolet light emitted from a first light source is irradiated onto a first surface of an object. FIG. [Figure 5]10 is a schematic cross-sectional view showing how light of peak light intensity among second ultraviolet light emitted from a second light source is irradiated onto a second surface of the object. FIG. [Figure 6] FIG. 2 is a schematic cross-sectional view showing an example of an object. [Figure 7] FIG. 10 is a schematic side view showing the configuration of an irradiation device according to a second embodiment. [Figure 8] 10 is a schematic cross-sectional view showing a state in which a first region of an object is irradiated with both third ultraviolet light at a third luminous intensity distribution angle from a third light source and fourth ultraviolet light at a fourth luminous intensity distribution angle from a fourth light source. FIG. [Figure 9] 10 is a schematic cross-sectional view showing a state in which only fourth ultraviolet light from a fourth light source at a fourth luminous intensity distribution angle is irradiated onto a second region of the object. FIG. [Figure 10] 10 is a schematic cross-sectional view showing how light of peak light intensity among third ultraviolet light emitted by a third light source is irradiated onto a first surface of an object. FIG. [Figure 11] 10 is a schematic cross-sectional view showing a state in which light of peak light intensity among fourth ultraviolet light emitted by a fourth light source is irradiated onto a second surface of the object. FIG. [Figure 12] FIG. 10 is a schematic side view showing the configuration of an irradiation device according to a third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] An irradiation device and an ultraviolet light irradiation method according to an embodiment of the present disclosure will be described in detail with reference to the drawings. However, the embodiments shown below are illustrative of an irradiation device and an ultraviolet light irradiation method for embodying the technical concept of the present embodiment, and are not limited thereto. Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative positions, etc. of components described in the embodiments are not intended to limit the scope of the present disclosure to those specific embodiments, and are merely illustrative examples. Note that the size, positional relationship, etc. of components shown in each drawing may be exaggerated for clarity. Furthermore, in the following description, the same names and symbols indicate the same or similar components, and detailed description will be omitted as appropriate.

[0011] In the following description, terms indicating specific directions or positions (for example, "up," "down," and other terms including these terms) may be used. These terms are used merely to facilitate understanding of the relationships of relative positions, orientations, directions, etc. in the referenced drawings, and may not necessarily coincide with the relationships when the light-emitting device according to the embodiment is in use. Furthermore, these directions are unrelated to the direction of gravity. Furthermore, in the terminology of this specification, the depth direction may also be referred to as the thickness direction of an object.

[0012] [First embodiment] <Configuration of the ultraviolet light irradiation device according to the first embodiment> The configuration of an ultraviolet light irradiation device according to the first embodiment will be described with reference to FIGS. 1 to 6. FIG. 1 is a schematic side view showing an example of an irradiation device 100 according to the first embodiment. FIG. 2 is a schematic cross-sectional view showing an example of how a first region Ar1 of an object S is irradiated with both first ultraviolet light U1 from a first light source 11 at a first light distribution angle φ1 and second ultraviolet light U2 from a second light source 12 at a second light distribution angle φ2. FIG. 3 is a schematic cross-sectional view showing an example of how a second region Ar2 of the object S is irradiated with only second ultraviolet light U2 from the second light source 12 at a second light distribution angle φ2. FIG. 4 is a schematic cross-sectional view showing an example of how a first surface S1 of the object S is irradiated with light of peak light intensity of the first ultraviolet light U1 from the first light source 11. FIG. 5 is a schematic cross-sectional view showing an example of how a second surface S2 of the object S is irradiated with light of peak light intensity of the second ultraviolet light U2 from the second light source 12. FIG. 6 is a schematic cross-sectional view showing an example of the target object S.

[0013] 1 to 5, arrows indicate portions of the first ultraviolet light U1 and the second ultraviolet light U2 emitted from the irradiation device 100. However, the arrows indicating the first ultraviolet light U1 and the second ultraviolet light U2 mean that the irradiation device 100 is capable of emitting each of the first ultraviolet light U1 and the second ultraviolet light U2. Therefore, the arrows indicating the first ultraviolet light U1 and the second ultraviolet light U2 do not mean that the irradiation device 100 is limited to emitting the first ultraviolet light U1 and the second ultraviolet light U2 simultaneously.

[0014] The irradiation device 100 is an irradiation device that irradiates light onto an object S, and includes a light-emitting device 1 equipped with a first light source 11 and a second light source 12 that irradiate ultraviolet light having different light distributions from each other, a mounting table 2 having a placement area 20 in which the object S is placed so that the ultraviolet light can be irradiated onto the object S, and an irradiation means 3 that irradiates the object S with the ultraviolet light from the first light source 11 before the ultraviolet light from the second light source 12.

[0015] 1, the first light source 11 and the second light source 12 are arranged inside the housing 10A. However, the first light source 11 and the second light source 12 may be arranged on the surface of the housing 10A. The first light source 11 irradiates the object S located below the housing 10A with first ultraviolet light U1. The second light source 12 irradiates the object S located below the housing 10A with second ultraviolet light U2.

[0016] Here, in an irradiation device that irradiates light onto the object S, depending on the shape of the object S, ultraviolet light from the irradiation device may not be properly irradiated onto a portion of the object S, resulting in uneven curing across the entire object S. For example, in FIG. 1, consider a case in which the first ultraviolet light U1 is irradiated onto the object S, which includes a first surface S1 that intersects with the first optical axis C1 of the first ultraviolet light U1 irradiated from the first light source 11, and a second surface S2 that is substantially parallel to the first optical axis C1, from an irradiation device having only the first light source 11. Because the first surface S1 intersects with the first optical axis C1, the first ultraviolet light U1 is properly irradiated onto the first surface S1, resulting in proper curing. On the other hand, because the second surface S2 is substantially parallel to the first optical axis C1, the first ultraviolet light from the first light source 11 is less likely to be irradiated onto the second surface S2, resulting in insufficient curing. As a result, the first surface S1 that is properly cured and the second surface S2 that is insufficiently cured are mixed in the object S, causing variations in curing of the object S.

[0017] The first optical axis C1 of the first ultraviolet light U1 emitted from the first light source 11 refers to an axis that is perpendicular to the light-emitting surface of the first light source 11 and passes through a point that indicates a peak in the light intensity distribution of the first light source 11. In the rest of this specification, the term "optical axis" will be used in the same sense.

[0018] The irradiation device 100 includes a first light source 11 and a second light source 12 that emit ultraviolet light having different light distributions, and the irradiation means 3 causes the ultraviolet light from the first light source 11 to irradiate the object S before the ultraviolet light from the second light source 12. This allows the ultraviolet light from at least one of the first light source 11 and the second light source 12 to be appropriately irradiated onto the second surface S2, even in cases where the object S includes a second surface S2 that is approximately parallel to the first optical axis C1. As a result, in this embodiment, it is possible to reduce areas that are insufficiently cured and reduce variations in curing of the object S.

[0019] The first light source 11 emits the first ultraviolet light U1 at a first light distribution angle φ1. The second light source 12 emits the second ultraviolet light at a second light distribution angle φ2 that is wider than the first light distribution angle φ1. The target object S includes a first region Ar1 that is irradiated with both the first ultraviolet light U1 from the first light source 11 and the second ultraviolet light U2 from the second light source 12, and a second region Ar2 that is irradiated with only the second ultraviolet light U2 from the second light source 12.

[0020] 2 and 3, the first region Ar1 faces the first light source 11 and the second light source 12 and includes a first surface S1 that intersects with the first optical axis C1 of the first ultraviolet light U1 and the second optical axis C2 of the second ultraviolet light U2. In FIG. 2, the first region Ar1 and the first surface S1 are indicated by the same reference numerals to indicate that the first region Ar1 includes the first surface S1. Hereinafter, the same reference numerals may be indicated by the same reference numerals for the same purpose. In FIG. 3, the second region Ar2 is an area that includes a second surface S2 that is substantially parallel to the first optical axis C1 of the first ultraviolet light U1 and the second optical axis C2 of the second ultraviolet light U2.

[0021] As shown in FIG. 2, both the first ultraviolet light U1 and the second ultraviolet light U2 are irradiated onto the first region Ar1. On the other hand, as shown in FIG. 3, the first ultraviolet light U1, which has a narrow light distribution angle, is only irradiated onto the second region Ar2 at a large incident angle. Therefore, the first ultraviolet light U1 is irradiated onto the second region Ar2 for a shorter period of time than the second ultraviolet light U2. That is, as shown in FIG. 3, the second region Ar2 is mainly irradiated with the second ultraviolet light U2. By irradiating the second region Ar2 with the second ultraviolet light U2, even when the target object S includes the second region Ar2, sufficient ultraviolet light can be irradiated onto the second region Ar2 to cure the target object S. This reduces variations in the curing of the target object S. Furthermore, by irradiating the first region Ar1 with both the first ultraviolet light U1 and the second ultraviolet light U2, the target object S can be cured in a shorter time than when only the second ultraviolet light U2 is irradiated.

[0022] The first light source 11 includes a first light-emitting element 111 and a first lens 112 disposed between the first light-emitting element 111 and the object S. The first lens 112 changes the light distribution angle of the ultraviolet light emitted from the first light-emitting element 111. The first lens 112 can make the first light distribution angle φ1 of the first ultraviolet light U1 emitted from the first light source 11 and the second light distribution angle φ2 of the second ultraviolet light U2 emitted from the second light source 12 different from each other. This makes it possible to irradiate the object S with ultraviolet light having different light distributions. Furthermore, for example, the first lens 112 narrows the light distribution angle of the ultraviolet light emitted from the first light-emitting element 111. This makes it possible to increase the irradiation intensity of the ultraviolet light on the object S.

[0023] The irradiation device 100 is not limited to a configuration in which the light distribution angle is different between the first light source 11 and the second light source 12. For example, the light distribution of the first light source 11 and the second light source 12 may be different by differentiating the directions of the optical axes of the ultraviolet light emitted by the first light source 11 and the second light source 12. A specific description will be given with reference to FIGS. 4 and 5. In FIGS. 4 and 5, the first light source 11 emits first ultraviolet light U1 having a first optical axis C1 in a first direction D1. The second light source 12 emits second ultraviolet light U2 having a second optical axis C2 in a second direction D2 different from the first direction D1. The object S has a first surface S1 and a second surface S2 that is continuous with the first surface S1 and is not parallel to the first surface S1. The light having the peak light intensity of the first ultraviolet light U1 emitted by the first light source 11 is irradiated onto the first surface S1, and the light having the peak light intensity of the second ultraviolet light U2 emitted by the second light source 12 is irradiated onto the second surface S2.

[0024] As shown in FIG. 4, the first surface S1 is irradiated with both the first ultraviolet light U1 and the second ultraviolet light U2. On the other hand, the second surface S2 is hardly irradiated with the first ultraviolet light U1, but is irradiated with the second ultraviolet light U2, which has a second optical axis C2 tilted relative to the first optical axis C1 of the first ultraviolet light U1. In other words, as shown in FIG. 5, the second surface S2 is mainly irradiated with the second ultraviolet light U2. By irradiating the second surface S2 with the second ultraviolet light U2, it is possible to irradiate the second surface S2 with ultraviolet light even when the target object S includes the second surface S2. This reduces variations in curing of the target object S.

[0025] 4 and 5, the second light source 12 includes a second light-emitting element 121 and a second lens 122 disposed between the second light-emitting element 121 and the object S. The second lens 122 changes the direction of the optical axis of the ultraviolet light emitted from the second light-emitting element 121. By changing the direction of the optical axis of the ultraviolet light emitted from the second light-emitting element 121, the second lens 122 causes the optical axis of the second ultraviolet light U2 emitted from the second light source 12 to become a second optical axis C2 tilted with respect to the first optical axis C1. The second lens 122 makes it possible to make the second direction D2 in which the second ultraviolet light U2 is emitted from the second light source 12 different from the first direction D1 in which the first ultraviolet light U1 is emitted from the first light source 11, and thus it is possible to irradiate the object S with ultraviolet light having different light directions of peak light intensities. In addition, by not providing the second lens 122 and mounting the second light-emitting element 121 at an angle relative to the first light-emitting element, the optical axis of the second ultraviolet light U2 emitted from the second light source 12 may be set to a second optical axis C2 that is inclined relative to the first optical axis C1.

[0026] On the other hand, from another perspective, the light emitting device 1 included in the irradiation device 100 is a light emitting device mounted on the irradiation device 100 that irradiates light onto the object S. The light emitting device 1 includes a first light source 11 and a second light source 12 that irradiate ultraviolet light having different light distributions. There is at least a non-overlapping area between the area irradiated with light from the first light source 11 and the area irradiated with light from the second light source 12. For example, the second area Ar2 and the second surface S2 in FIGS. 1 to 3 are areas that are not irradiated with light from the first light source 11 but are irradiated with light from the second light source 12, and therefore correspond to the "at least non-overlapping area."

[0027] In the light emitting device 1, the area irradiated with light from the first light source 11 and the area irradiated with light from the second light source 12 are different, resulting in the "at least non-overlapping area." As a result, the first surface S1 and the second surface S2 can be appropriately irradiated with ultraviolet light from at least one of the first light source 11 and the second light source 12. As a result, in this embodiment, it is possible to reduce areas where curing is insufficient, and reduce variations in curing of the target object S.

[0028] The first light source 11 in the light emitting device 1 emits ultraviolet light at a first light distribution angle φ1, and the second light source 12 emits ultraviolet light at a second light distribution angle φ2 that is different from the first light distribution angle φ1. This allows the light emitting device 1 to irradiate the object S with ultraviolet light having mutually different light distributions.

[0029] As shown in FIG. 6, the object S includes a substrate T and a coating material P applied to the surface of the substrate T. The substrate T shown in FIG. 6 is a bowl-shaped object including a recess T0. However, there are no particular limitations on the shape and material of the substrate T. The thickness of the coating material P is, for example, 5 μm or more and 300 μm or less. The coating material P on the object S is cured by being irradiated with ultraviolet light from the irradiation device 100. From another perspective, the curing of the object S is the curing of the coating material P. However, the object applied to the object S is not limited to the coating material P, and may be an object other than the coating material P, such as ink, adhesive, or coating agent, as long as it is cured by being irradiated with ultraviolet light U.

[0030] In the example shown in FIG. 1 , the object S is transported in a moving direction A indicated by an arrow by a transport mechanism such as a conveyor. The irradiation device 100 can irradiate the object S transported in the moving direction A from above with a first ultraviolet light U1 and a second ultraviolet light U2. However, the irradiation device 100 is not limited to irradiating the object S being transported with the first ultraviolet light U1 and the second ultraviolet light U2, and may irradiate a stationary object S with the first ultraviolet light U1 and the second ultraviolet light U2. The irradiation device 100 may irradiate the object S with the first ultraviolet light U1 and the second ultraviolet light U2 after irradiating the object S with the first ultraviolet light U1. Alternatively, the irradiation device 100 may move the light-emitting device 1 to irradiate a stationary or transported object S with the first ultraviolet light U1 and the second ultraviolet light U2. Furthermore, the irradiation of the first ultraviolet light U1 and the second ultraviolet light U2 by the irradiation device 100 is not limited to irradiation onto the upper surface of the object S from above, but may also be irradiation onto the lower surface of the object S from below, or irradiation onto the side surface of the object S from the side.

[0031] The first light source 11 and the second light source 12 each include a light-emitting element, which may be, for example, a light-emitting diode (LED). Each of the light-emitting elements may include one or more light-emitting diodes. When the light-emitting element includes multiple light-emitting diodes, it is preferable that the multiple light-emitting diodes are made of the same material. When the first light source 11 and the second light source 12 each include a light-emitting diode, heat generation by the irradiation device 100 can be reduced.

[0032] Any type of mounting table 2 may be used as long as it has a placement area 20 where the object S is placed so that the object S can be irradiated with ultraviolet light.

[0033] The irradiation means 3 has a physical mechanism that causes the ultraviolet light from the first light source 11 to be irradiated onto the object S before the ultraviolet light from the second light source 12. As the irradiation means 3, for example, any of the following (1) to (4) can be adopted. (1) This is achieved by moving the object S using a conveyor or other transport mechanism. (2) This is realized by moving the light emitting device 1 using a moving device or the like. (3) This is achieved by placing the object S in one place and having the CPU (Central Processing Unit) execute the processing specified in the program stored in non-volatile memory such as ROM (Read Only Memory), or by controlling the order of irradiation using electrical or electronic circuits, etc. (4) This is realized by providing switches that can individually turn on or off the first light source 11 and the second light source 12. In the case of (4), an operator such as a user of the irradiation device 100 may switch the switches.

[0034] 1 controls the irradiance of each of the first light source 11 and the second light source 12 by controlling the current value of the drive current supplied to each of the light-emitting elements included in each of the first light source 11 and the second light source 12. In addition, the illumination means 3 controls the illumination time of each of the first light source 11 and the second light source 12 by controlling the timing of supplying or stopping the supply of the drive current to each of the first light source 11 and the second light source 12. Furthermore, the illumination means 3 controls the illumination time and illumination timing of each of the first light source 11 and the second light source 12 to the object S by moving the object S relative to the light-emitting device 1.

[0035] [Second embodiment] Next, an irradiation device according to a second embodiment will be described. Note that the same names and symbols as those in the previously described embodiments indicate the same or similar components or configurations, and detailed descriptions will be omitted as appropriate. This also applies to the following embodiments.

[0036] <Configuration of the irradiation device according to the second embodiment> The configuration of the irradiation device according to the second embodiment will be described with reference to FIGS. 7 to 11. FIG. 7 is a schematic side view showing an example of the configuration of the irradiation device 100a according to the second embodiment. FIG. 8 is a schematic cross-sectional view showing an example of how both the third ultraviolet light U3 emitted by the third light source 13 with the third luminous intensity distribution angle φ3 and the fourth ultraviolet light U4 emitted by the fourth light source 14 with the fourth luminous intensity distribution angle φ4 are irradiated onto a first region Ar1 of the object S. FIG. 9 is a schematic cross-sectional view showing an example of how only the fourth ultraviolet light U4 emitted by the fourth light source 14 with the fourth luminous intensity distribution angle φ4 is irradiated onto a second region Ar2 of the object S. FIG. 10 is a schematic cross-sectional view showing an example of how the third ultraviolet light U3 emitted by the third light source 13 with the peak light intensity is irradiated onto a first surface S1 of the object S. FIG. 11 is a schematic cross-sectional view showing an example of how the fourth ultraviolet light U4 emitted by the fourth light source 14 with the peak light intensity is irradiated onto a second surface S2 of the object S.

[0037] 7 to 11, arrows indicate portions of the first ultraviolet light U1, second ultraviolet light U2, third ultraviolet light U3, and fourth ultraviolet light U4 emitted from the irradiation device 100a. However, the arrows indicating the first ultraviolet light U1, second ultraviolet light U2, third ultraviolet light U3, and fourth ultraviolet light U4 mean that the irradiation device 100a can emit each of the first ultraviolet light U1, second ultraviolet light U2, third ultraviolet light U3, and fourth ultraviolet light U4. Therefore, the arrows indicating the first ultraviolet light U1, second ultraviolet light U2, third ultraviolet light U3, and fourth ultraviolet light U4 do not mean that the irradiation device 100a is limited to simultaneously emitting the first ultraviolet light U1, second ultraviolet light U2, third ultraviolet light U3, and fourth ultraviolet light U4.

[0038] In the irradiation device 100a, the first light source 11 and the second light source 12 emit ultraviolet light having a first emission peak wavelength. The irradiation device 100a further includes a third light source 13 and a fourth light source 14 that emit ultraviolet light having a second emission peak wavelength different from the first emission peak wavelength. The difference between the first emission peak wavelength and the second emission peak wavelength is, for example, 70 nm or more and 150 nm or less. The third light source 13 emits the ultraviolet light at a third luminous intensity distribution angle φ3. The fourth light source 14 emits the ultraviolet light at a fourth luminous intensity distribution angle φ4 that is wider than the third luminous intensity distribution angle φ3. The object S includes a first region Ar1 irradiated with both the light from the third light source 13 and the light from the fourth light source, and a second region Ar2 irradiated with only the light from the fourth light source 14. The irradiation means 3 irradiates the object S with the ultraviolet light having the first emission peak wavelength before the ultraviolet light having the second emission peak wavelength.

[0039] 7, the third light source 13 and the fourth light source 14 are disposed inside the housing 10B. However, the third light source 13 and the fourth light source 14 may be disposed on the surface of the housing 10B. The third light source 13 irradiates the object S located below the housing 10B with third ultraviolet light U3. The fourth light source 14 irradiates the object S located below the housing 10B with fourth ultraviolet light U4.

[0040] For example, when the target object S is irradiated with multiple ultraviolet light beams having different peak emission wavelengths for curing, the absorbency of the ultraviolet light varies depending on the depth inside the target object S from the surface on the side where the light-emitting device 1 is located, depending on the peak emission wavelength, which may result in curing variations. Specifically, if ultraviolet light with a peak emission wavelength that is absorbed within the target object S and therefore does not reach deep positions is irradiated first, only shallow positions inside the target object S will be cured. After the shallow positions inside the target object S are cured, even if ultraviolet light with a peak emission wavelength that can reach deep positions inside the target object S is subsequently irradiated, the progress of the ultraviolet light will be hindered by the cured region at the shallow positions inside the target object S, preventing it from reaching deep positions. This makes it impossible to cure deep positions inside the target object S. As a result, the target object S will cure at shallow positions, but will not cure sufficiently at deeper positions. On the other hand, if only ultraviolet light with a peak emission wavelength that can reach deep positions inside the object S is irradiated, curing will proceed in deep positions in the object S, but curing will be insufficient in shallow positions. Therefore, unless multiple ultraviolet light beams with different peak emission wavelengths are irradiated, there is a risk that curing variations will occur in the object S.

[0041] In the irradiation device 100a, the first ultraviolet light U1 and the second ultraviolet light U2, which have a first emission peak wavelength and can reach deep positions in the object S without being absorbed, are irradiated onto the object S before the third ultraviolet light U3 and the fourth ultraviolet light U4, which have a second emission peak wavelength. This allows the deep positions of the object S to be cured before the shallow positions of the object S. After the deep positions are cured, the shallow positions of the object S can be cured by irradiating the object S with the third ultraviolet light U3 and the fourth ultraviolet light U4, which have the second emission peak wavelength. Here, if the object S consists of a substrate T and a coating material P applied to the surface of the substrate T, a shallow position refers to, for example, a region up to a predetermined distance from the surface of the coating material P, and a deep position refers to a region of the coating material P that is further away than the predetermined distance. The predetermined distance is, for example, 45 μm or more and 75 μm or less. If the thickness of the coating material P is shorter than the predetermined distance, the entire region of the coating material P can be considered to be a shallow position. In this way, by appropriately combining and using the first ultraviolet light U1 and second ultraviolet light U2 having the first emission peak wavelength and the third ultraviolet light U3 and fourth ultraviolet light U4 having the second emission peak wavelength, the object S can be cured appropriately from deep positions to the surface, and variation in curing of the object S can be reduced.

[0042] In the example shown in FIG. 7, the first emission peak wavelength is 360 nm or more and 410 nm or less. The second emission peak wavelength is 260 nm or more and 290 nm or less. By setting the first emission peak wavelength to 360 nm or more and 410 nm or less, light of the first emission peak wavelength can reach deep positions inside the object S without being absorbed, and can cure the object S. By setting the second emission peak wavelength to 260 nm or more and 290 nm or less, it is possible to cure shallow positions inside the object S. As a result, the object S can be cured appropriately from deep positions to the surface, and variation in curing of the object S can be reduced.

[0043] The object S moves relative to the irradiation device in the movement direction A. The first light source 11 and the second light source 12 are disposed upstream of the third light source 13 and the fourth light source 14 in the movement direction A. By moving the object S relative to the irradiation device, the ultraviolet light having the first emission peak wavelength from the first light source 11 and the second light source 12 and the ultraviolet light having the second emission peak wavelength from the third light source 13 and the fourth light source 14 can be irradiated onto the same position on the object S. By irradiating the object S with the ultraviolet light having the first emission peak wavelength before the ultraviolet light having the second emission peak wavelength, the object S can be suitably cured from deep positions to the surface, and variation in curing of the object S can be reduced.

[0044] In the illumination device 100a, the distance d2 between the second light source 12 and the third light source 13 in the movement direction A is longer than the distance d1 between the first light source 11 and the second light source 12. This makes it possible to avoid interference between the second light source 12 and the third light source 13. In other words, it is possible to reduce the possibility that the light from the third light source 13 will be irradiated onto the object S before the light from the second light source 12.

[0045] The third light source 13 emits the third ultraviolet light U3 at a third light distribution angle φ3. The fourth light source 14 emits the fourth ultraviolet light at a fourth light distribution angle φ4 that is wider than the third light distribution angle φ3. The target object S includes a first region Ar1 that is irradiated with both the third ultraviolet light U3 from the third light source 13 and the fourth ultraviolet light U4 from the fourth light source 14, and a second region Ar2 that is irradiated with only the fourth ultraviolet light U4 from the fourth light source 14.

[0046] 8 and 9, the first region Ar1 is a region facing the third light source 13 and the fourth light source 14 and including a first surface S1 that intersects with each of the third optical axis C3 of the third ultraviolet light U3 and the fourth optical axis C4 of the fourth ultraviolet light U4. In Fig. 9, the second region Ar2 is a region that includes a second surface S2 that is approximately parallel to each of the third optical axis C3 of the third ultraviolet light U3 and the fourth optical axis C4 of the fourth ultraviolet light U4.

[0047] As shown in Fig. 8, the first region Ar1 is irradiated with both the third ultraviolet light U3 and the fourth ultraviolet light U4. On the other hand, the second region Ar2 is hardly irradiated with the third ultraviolet light U3, which has a narrow light distribution angle, and is irradiated with the fourth ultraviolet light U4, which has a wider light distribution angle than the third ultraviolet light U3. In other words, as shown in Fig. 9, the second region Ar2 is mainly irradiated with the fourth ultraviolet light U4. By irradiating the second region Ar2 with the fourth ultraviolet light U4, it becomes possible to irradiate the second region Ar2 with ultraviolet light even when the target object S includes the second region Ar2, thereby reducing variations in curing of the target object S.

[0048] The third light source 13 includes a third light-emitting element 131 and a third lens 132 disposed between the third light-emitting element 131 and the object S. The third lens 132 changes the light distribution angle of the ultraviolet light emitted from the third light-emitting element 131. The third lens 132 makes it possible to make the third light distribution angle φ3 of the third ultraviolet light U3 emitted from the third light source 13 different from the fourth light distribution angle φ4 of the fourth ultraviolet light U4 emitted from the fourth light source 14. This makes it possible to irradiate the object S with ultraviolet light having different light distributions.

[0049] In the irradiation device 100a shown in Fig. 7, the first light distribution angle φ1 and the third light distribution angle φ3 are each 30 degrees or more and 70 degrees or less. The second light distribution angle φ2 and the fourth light distribution angle φ4 are each 110 degrees or more and 130 degrees or less. By satisfying these conditions, the irradiation device 100a can irradiate the second area Ar2 with ultraviolet light even when the object S includes the second area Ar2. This reduces variations in curing of the object S.

[0050] The illumination device 100a is not limited to a configuration in which the light distribution angle is different between the third light source 13 and the fourth light source 14. For example, the directions of the optical axes of the ultraviolet light emitted by the third light source 13 and the fourth light source 14 may be different. A specific description will be given with reference to FIGS. 10 and 11. In FIGS. 10 and 11, in the illumination device 100a, the third light source 13 emits ultraviolet light whose optical axis is in a third direction. The fourth light source 14 emits ultraviolet light whose optical axis is in a fourth direction D4 different from the third direction D3. The target object S includes a first region Ar1 that is irradiated with both the light from the third light source 13 and the light from the fourth light source 14, and a second region Ar2 that is irradiated with only the light from the fourth light source 14.

[0051] As shown in FIG. 10, the first region Ar1 is irradiated with both the third ultraviolet light U3 and the fourth ultraviolet light U4. On the other hand, the second region Ar2 is hardly irradiated with the third ultraviolet light U3, but is irradiated with the fourth ultraviolet light U4, which has a fourth optical axis C4 tilted relative to the third optical axis C3 of the third ultraviolet light U3. In other words, as shown in FIG. 11, the second region Ar2 is mainly irradiated with the fourth ultraviolet light U4. By irradiating the second region Ar2 with the fourth ultraviolet light U4, it is possible to irradiate the second region Ar2 with ultraviolet light even when the target object S includes the second region Ar2. This reduces variations in curing of the target object S.

[0052] The fourth light source 14 includes a fourth light-emitting element 141 and a fourth lens 142 disposed between the fourth light-emitting element 141 and the object S. The fourth lens 142 changes the light distribution angle of the ultraviolet light emitted from the fourth light-emitting element 141. The fourth lens 142 changes the direction of the optical axis of the ultraviolet light emitted from the fourth light-emitting element 141, so that the optical axis of the fourth ultraviolet light U4 emitted from the fourth light source 14 becomes a fourth optical axis C4 that is tilted with respect to the third optical axis C3. The fourth lens 142 makes it possible to make the fourth light distribution angle φ4 of the fourth ultraviolet light U4 emitted from the fourth light source 14 different from the third light distribution angle φ3 of the third ultraviolet light U3 emitted from the third light source 13, and thus it is possible to irradiate the object S with ultraviolet light having different light distributions. In addition, by not providing the fourth lens 142 and mounting the fourth light-emitting element 141 at an angle, the optical axis of the fourth ultraviolet light U4 emitted from the fourth light source 14 may be a fourth optical axis C4 that is inclined relative to the third optical axis C3.

[0053] The third light source 13 and the fourth light source 14 each include a light-emitting element, which may be, for example, a light-emitting diode. Each of the light-emitting elements may include one or more light-emitting diodes. When the light-emitting element includes multiple light-emitting diodes, the multiple light-emitting diodes are preferably made of the same material. When the third light source 13 and the fourth light source 14 each include a light-emitting diode, the illumination device 100a can be made smaller.

[0054] On the other hand, from another perspective, light emitting device 1a further includes third light source 13 and fourth light source 14 that emit ultraviolet light having different light distributions from each other. First light source 11 and second light source 12 emit ultraviolet light having a first emission peak wavelength. Third light source 13 and fourth light source 14 emit ultraviolet light having a second emission peak wavelength different from the first emission peak wavelength. Third light source 13 emits ultraviolet light at a third luminous intensity distribution angle φ3. Fourth light source 14 emits ultraviolet light at a fourth luminous intensity distribution angle φ4 that is wider than the third luminous intensity distribution angle φ3. Target object S includes a first region Ar1 that is irradiated with both the light from third light source 13 and the light from fourth light source 14, and a second region Ar2 that is irradiated with only the light from fourth light source 14.

[0055] In the light emitting device 1a, even when the object S includes a second surface S2 that is approximately parallel to the first optical axis C1, the second surface S2 can be appropriately irradiated with ultraviolet light from at least one of the first light source 11 and the second light source 12. As a result, the light emitting device 1a can reduce areas that are insufficiently cured and reduce variations in curing of the object S.

[0056] <Ultraviolet Light Irradiation Method Using Irradiation Device 100a According to Second Embodiment> The irradiation device 100a irradiates ultraviolet light of a first emission peak wavelength having different light distributions from the first light source 11 and the second light source 12, and irradiates ultraviolet light of a second emission peak wavelength shorter than the first emission peak wavelength having different light distributions from the third light source 13 and the fourth light source 14. Furthermore, the irradiation device 100a irradiates the object S with the ultraviolet light of the first emission peak wavelength before the ultraviolet light of the second emission peak wavelength.

[0057] Specifically, the irradiation device 100a irradiates the object S with first ultraviolet light U1 having a first emission peak wavelength at a first luminous intensity distribution angle φ1 using the first light source 11. The irradiation device 100a irradiates the object S with second ultraviolet light U2 having a first emission peak wavelength at a second luminous intensity distribution angle φ2, which is different from the first luminous intensity distribution angle φ1, using the second light source 12. The irradiation device 100a irradiates the object S with third ultraviolet light U3 having a second emission peak wavelength at a third luminous intensity distribution angle φ3 using the third light source 13. The irradiation device 100a irradiates the object S with fourth ultraviolet light U4 having a second emission peak wavelength at a fourth luminous intensity distribution angle φ4, which is different from the third luminous intensity distribution angle φ3, using the fourth light source 14. The irradiation device 100a irradiates the object S with the first ultraviolet light U1 and the second ultraviolet light U2 before the object S with the third ultraviolet light U3 and the fourth ultraviolet light U4. As described above, in the ultraviolet light irradiation method according to this embodiment, the object S can be suitably cured from deep positions to the surface, and variations in curing of the object S can be reduced.

[0058] Furthermore, the irradiation device 100a irradiates ultraviolet light onto the object S that moves relatively in the movement direction A, and the first light source 11 and the second light source 12 are disposed upstream in the movement direction A from the third light source 13 and the fourth light source 14. This allows the first ultraviolet light U1 and the second ultraviolet light U2 having a first emission peak wavelength from the first light source 11 and the second light source 12 to be irradiated onto the object S before the third ultraviolet light U3 and the fourth ultraviolet light U4 having a second emission peak wavelength from the third light source 13 and the fourth light source 14. As a result, the irradiation device 100a can suitably cure the object S from deep positions to the surface, thereby reducing variation in curing of the object S.

[0059] [Third embodiment] Next, an irradiation device according to a third embodiment will be described.

[0060] Fig. 12 is a schematic side view showing an example of the configuration of an irradiation device 100b according to the third embodiment. In Fig. 12, arrows indicate portions of the first ultraviolet light U1, second ultraviolet light U2, third ultraviolet light U3, fourth ultraviolet light U4, fifth ultraviolet light U5, and sixth ultraviolet light U6 emitted from the irradiation device 100b. The arrows indicating the first ultraviolet light U1, second ultraviolet light U2, third ultraviolet light U3, fourth ultraviolet light U4, fifth ultraviolet light U5, and sixth ultraviolet light U6 indicate that the irradiation device 100b can irradiate the first ultraviolet light U1, second ultraviolet light U2, third ultraviolet light U3, fourth ultraviolet light U4, fifth ultraviolet light U5, and sixth ultraviolet light U6, respectively. Therefore, the arrows indicating the first ultraviolet light U1, the second ultraviolet light U2, the third ultraviolet light U3, the fourth ultraviolet light U4, the fifth ultraviolet light U5, and the sixth ultraviolet light U6 do not mean that the irradiation device 100b is limited to simultaneously irradiating the first ultraviolet light U1, the second ultraviolet light U2, the third ultraviolet light U3, the fourth ultraviolet light U4, the fifth ultraviolet light U5, and the sixth ultraviolet light U6.

[0061] The irradiation device 100b has a fifth light source 15 and a sixth light source 16 that emit ultraviolet light having a third emission peak wavelength different from both the first emission peak wavelength and the second emission peak wavelength and that have different light distributions from each other. The fifth light source 15 and the sixth light source 16 are disposed between the first light source 11 and the second light source 12 and the third light source 13 and the fourth light source 14 in the movement direction A. The third emission peak wavelength is shorter than the first emission peak wavelength and longer than the second emission peak wavelength.

[0062] 12, the fifth light source 15 and the sixth light source 16 are disposed inside the housing 10C. The fifth light source 15 irradiates the object S located below the housing 10C with fifth ultraviolet light U5. The sixth light source 16 irradiates the object S located below the housing 10C with sixth ultraviolet light U6.

[0063] The irradiation device 100b first irradiates the target S with first ultraviolet light U1 and second ultraviolet light U2 having a first emission peak wavelength that can reach deep positions within the target S without being absorbed, then irradiates the target S with fifth ultraviolet light U5 and sixth ultraviolet light U6 having a third emission peak wavelength that can reach deeper positions within the target S than the second emission peak wavelength without being absorbed, and finally irradiates the target S with third ultraviolet light U3 and fourth ultraviolet light U4 having the second emission peak wavelength. Because the light with the third emission peak wavelength is shorter than the first emission peak wavelength but longer than the second emission peak wavelength, it can effectively cure a region in the depth direction within the target S between the region cured with the ultraviolet light with the first emission peak wavelength and the region cured with the ultraviolet light with the second emission peak wavelength. Furthermore, the target S can be considered to include a region cured with the ultraviolet light with the first emission peak wavelength, a region cured with the ultraviolet light with the third emission peak wavelength, and a region cured with the ultraviolet light with the second emission peak wavelength. Here, when the target object S consists of a substrate T and a coating material P applied to the surface of the substrate T, the region cured with ultraviolet light having a first emission peak wavelength is, for example, a region that is further away from the surface of the coating material P by a predetermined first distance, and the region cured with ultraviolet light having a second emission peak wavelength is, for example, a region that is further away from the surface of the coating material P by a predetermined second distance. Furthermore, the region between the region cured with ultraviolet light having a first emission peak wavelength and the region cured with ultraviolet light having a second emission peak wavelength is, for example, a region that is further away from the surface of the coating material P by the predetermined first distance and further away from the surface of the coating material P by a predetermined second distance. The predetermined first distance is, for example, 90 μm or more and 135 μm or less. The predetermined second distance is, for example, 45 μm or more and 75 μm or less. When the thickness of the coating material P is shorter than the predetermined second distance, the entire region of the coating material P can be considered to be cured with ultraviolet light having a second emission peak wavelength. When the thickness of the coating material P is shorter than the first predetermined distance and longer than the second predetermined distance, the coating material P can be considered to consist of a region cured with ultraviolet light having the second emission peak wavelength and a region cured with ultraviolet light having the third emission peak wavelength. In this way, the presence of the fifth ultraviolet light U5 and the sixth ultraviolet light U6 reduces the uncured region, allowing the target object S to be cured efficiently. As a result, variation in curing of the target object S in the depth direction can be reduced.

[0064] 12, the third emission peak wavelength is 300 nm or more and 350 nm or less, which allows the region in the depth direction inside the object S between the region cured with ultraviolet light of the first emission peak wavelength and the region cured with ultraviolet light of the second emission peak wavelength to be suitably cured.

[0065] The fifth light source 15 includes a fifth light-emitting element 151 and a fifth lens 152 disposed between the fifth light-emitting element 151 and the object S. The fifth lens 152 changes the light distribution angle of the ultraviolet light emitted from the fifth light-emitting element 151. The fifth lens 152 makes it possible to make the fifth light distribution angle φ5 of the fifth ultraviolet light U5 emitted from the fifth light source 15 different from the sixth light distribution angle φ6 of the sixth ultraviolet light U6 emitted from the sixth light source 16, and thus it is possible to irradiate the object S with ultraviolet light having different light distributions.

[0066] Although the preferred embodiments have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0067] All ordinal numbers, quantitative numbers, and other figures used in the description of the embodiments are provided as examples to specifically explain the technology of the present disclosure, and the present disclosure is not limited to the illustrated figures. Furthermore, the connection relationships between components are provided as examples to specifically explain the technology of the present disclosure, and do not limit the connection relationships that realize the functions of the present disclosure.

[0068] The ultraviolet light irradiation method of the present disclosure can reduce variations in the curing of an object, and is therefore suitable for use in applications such as painting, coating, printing, and exposure, in which an object is irradiated with ultraviolet light to cure the object. From the viewpoint of efficiently curing objects with a thickness of 10 μm or more, the method is particularly suitable for painting vehicles such as automobiles. However, the ultraviolet light irradiation method of the present disclosure is not limited to these applications.

[0069] Aspects of the present disclosure are, for example, as follows. <Item 1> An irradiation device that irradiates an object with light, the irradiation device comprising: a light-emitting device having a first light source and a second light source that irradiate ultraviolet light having different light distributions from each other; a mounting table having a placement area where the object is placed to be irradiated with the ultraviolet light; and irradiation means that irradiates the object with the ultraviolet light from the first light source before the ultraviolet light from the second light source. <Item 2> The irradiation device according to <Item 1>, wherein the first light source emits ultraviolet light at a first light distribution angle, the second light source emits ultraviolet light at a second light distribution angle wider than the first light distribution angle, and the target object includes an area irradiated with both the light from the first light source and the light from the second light source, and an area irradiated with only the light from the second light source. <Item 3> The irradiation device according to <Item 2>, wherein the first light source includes a first light-emitting element and a first lens disposed between the first light-emitting element and the object, and the first lens changes a light distribution angle of the ultraviolet light emitted from the first light-emitting element. <Item 4> The irradiation device according to any one of <Item 1> to <Item 3>, wherein the first light source emits ultraviolet light having an optical axis in a first direction, the second light source emits ultraviolet light having an optical axis in a second direction different from the first direction, the object has a first surface and a second surface that is continuous with the first surface and is not parallel to the first surface, and light having a peak light intensity from the light emitted by the first light source is irradiated onto the first surface, and light having a peak light intensity from the light emitted by the second light source is irradiated onto the second surface. <Item 5> The irradiation device according to <Item 4>, wherein the second light source includes a second light-emitting element and a second lens disposed between the second light-emitting element and the object, and the second lens changes the direction of the optical axis of the ultraviolet light emitted from the second light-emitting element. <Item 6> The irradiation device according to <Item 2>, wherein the first light source and the second light source emit ultraviolet light of a first emission peak wavelength, and further include a third light source and a fourth light source that emit ultraviolet light of a second emission peak wavelength different from the first emission peak wavelength, the third light source emits the ultraviolet light at a third luminous intensity distribution angle, and the fourth light source emits the ultraviolet light at a fourth luminous intensity distribution angle that is wider than the third luminous intensity distribution angle, the object includes a region that is irradiated with both light from the third light source and light from the fourth light source, and a region that is irradiated with only light from the fourth light source, and the irradiation means irradiates the object with the ultraviolet light of the first emission peak wavelength before the ultraviolet light of the second emission peak wavelength. <Item 7> The illumination device according to <Item 6>, wherein the first light distribution angle and the third light distribution angle are each equal to or greater than 30 degrees and equal to or less than 70 degrees, and the second light distribution angle and the fourth light distribution angle are each equal to or greater than 110 degrees and equal to or less than 130 degrees. <Item 8> The irradiation device according to <Item 2>, wherein the first light source and the second light source emit ultraviolet light of a first emission peak wavelength, and further include a third light source and a fourth light source that emit ultraviolet light of a second emission peak wavelength different from the first emission peak wavelength, the third light source emits ultraviolet light having an optical axis in a third direction, and the fourth light source emits ultraviolet light having an optical axis in a fourth direction different from the third direction, and the object includes a region that is irradiated with both the light from the third light source and the light from the fourth light source, and a region that is irradiated with only the light from the fourth light source. <Item 9> The illumination device according to any one of <Item 1> to <Item 8>, wherein the first light source and the second light source each include a light emitting diode. <Item 10> The first emission peak wavelength is 360 nm or more and 410 nm or less, and the second emission peak wavelength is 260 nm or more and 290 nm or less, <7> The irradiation device is as described in the above. <Item 11> The illumination device according to <Item 8>, wherein the object moves relative to the illumination device in a movement direction, and the first light source and the second light source are disposed upstream of the third light source and the fourth light source in the movement direction. <Item 12> The illumination device according to <Item 11>, wherein the distance between the second light source and the third light source in the movement direction is longer than the distance between the first light source and the second light source. <Item 13> The irradiation device according to <Item 11> or <Item 12>, further comprising: a fifth light source and a sixth light source that irradiate ultraviolet light of a third emission peak wavelength that is different from both the first emission peak wavelength and the second emission peak wavelength and that have different light distributions from each other, and the fifth light source and the sixth light source are disposed between the first light source and the second light source and the third light source and the fourth light source in the movement direction. <Item 14> The irradiation device according to <Item 13>, wherein the third emission peak wavelength is 300 nm or more and 350 nm or less. <Item 15> A light emitting device mounted in an irradiation device that irradiates an object with light, the light emitting device comprising a first light source and a second light source that irradiate ultraviolet light with different light distributions, wherein there is at least a non-overlapping area between an area irradiated with light from the first light source and an area irradiated with light from the second light source. <Item 16> The light emitting device according to <Item 15>, wherein the first light source emits ultraviolet light at a first light distribution angle, and the second light source emits ultraviolet light at a second light distribution angle that is wider than the first light distribution angle. <Item 17> The light emitting device according to <Item 16>, further comprising a third light source and a fourth light source that emit ultraviolet light having different light distributions from each other, wherein the first light source and the second light source emit ultraviolet light of a first emission peak wavelength, the third light source and the fourth light source emit ultraviolet light of a second emission peak wavelength that is different from the first emission peak wavelength, the third light source emits the ultraviolet light at a third light distribution angle, and the fourth light source emits the ultraviolet light at a fourth light distribution angle that is wider than the third light distribution angle, and the target object includes a region that is irradiated with both the light from the third light source and the light from the fourth light source, and a region that is irradiated with only the light from the fourth light source. <Item 18> A method of irradiating ultraviolet light using an irradiation device, the irradiation device irradiating ultraviolet light of a first emission peak wavelength having different light distributions from a first light source and a second light source, irradiating ultraviolet light of a second emission peak wavelength shorter than the first emission peak wavelength and having different light distributions from a third light source and a fourth light source, and irradiating the ultraviolet light of the first emission peak wavelength onto an object before the ultraviolet light of the second emission peak wavelength. <Item 19> The ultraviolet light irradiation method according to <Item 18>, wherein the irradiation device irradiates the ultraviolet light onto an object that moves relatively in a movement direction, and the first light source and the second light source are arranged upstream of the third light source and the fourth light source in the movement direction. [Explanation of symbols]

[0070] 1, 1a Light-emitting device 11 1st light source 111 first light-emitting element 112 First lens 12 Second light source 121 second light-emitting element 122 Second lens 13 Third light source 131 third light-emitting element 132 Third lens 14 4th light source 15 5th light source 151 5th light-emitting element 162 6th lens 16 6th light source 2 Mounting table 20 Placement area 3 Irradiation means 10A, 10B, 10C housing 100, 100a, 100b irradiation equipment A. Direction of movement Ar1 1st area Ar2 2nd area C1 1st optical axis C2 2nd optical axis C3 3rd optical axis C4 4th optical axis D1 1st direction D2 2nd direction d1 distance d2 distance S Object S1 1st page S2 side 2 U1 1st ultraviolet light U2 2nd ultraviolet light U3 Third ultraviolet light U4 4th ultraviolet light U5 5th ultraviolet light U6 6th ultraviolet light φ1 First light distribution angle φ2 Second light distribution angle φ3 3rd light distribution angle φ4 4th light distribution angle φ5 5th light distribution angle φ6 6th light distribution angle

Claims

1. An illumination device that illuminates an object with light, a light emitting device including a first light source and a second light source that emit ultraviolet light having different light distributions; a mounting table having a placement area where the object is placed so that the object can be irradiated with the ultraviolet light; an irradiation means for irradiating the object with the ultraviolet light from the first light source before the ultraviolet light from the second light source is irradiated onto the object.

2. the first light source emits ultraviolet light at a first luminous intensity distribution angle; the second light source emits ultraviolet light at a second light distribution angle that is wider than the first light distribution angle, 2. The illumination device according to claim 1, wherein the object includes an area illuminated by both the light from the first light source and the light from the second light source, and an area illuminated by only the light from the second light source.

3. the first light source includes a first light-emitting element and a first lens disposed between the first light-emitting element and the object; The irradiation device according to claim 2 , wherein the first lens changes a light distribution angle of the ultraviolet light emitted from the first light-emitting element.

4. the first light source emits ultraviolet light having an optical axis in a first direction; the second light source emits ultraviolet light having an optical axis in a second direction different from the first direction, the object has a first surface and a second surface that is continuous with the first surface and is not parallel to the first surface; light having a peak light intensity from the first light source is irradiated onto the first surface; The illumination device according to claim 1 , wherein light of a peak light intensity from the second light source is irradiated onto the second surface.

5. the second light source includes a second light-emitting element and a second lens disposed between the second light-emitting element and the object; The irradiation device according to claim 4 , wherein the second lens changes the direction of the optical axis of the ultraviolet light emitted from the second light-emitting element.

6. the first light source and the second light source emit ultraviolet light having a first emission peak wavelength, further comprising a third light source and a fourth light source that emit ultraviolet light having a second emission peak wavelength different from the first emission peak wavelength, the third light source emits ultraviolet light at a third luminous intensity distribution angle, the fourth light source emits ultraviolet light at a fourth light distribution angle that is wider than the third light distribution angle, the target object includes a region irradiated with both the light from the third light source and the light from the fourth light source, and a region irradiated with only the light from the fourth light source, The irradiation device according to claim 2 , wherein the irradiation means irradiates the object with the ultraviolet light having the first emission peak wavelength before irradiating the object with the ultraviolet light having the second emission peak wavelength.

7. the first light distribution angle and the third light distribution angle are each equal to or greater than 30 degrees and equal to or less than 70 degrees, The illumination device according to claim 6 , wherein the second light distribution angle and the fourth light distribution angle are each equal to or greater than 110 degrees and equal to or less than 130 degrees.

8. the first light source and the second light source emit ultraviolet light having a first emission peak wavelength, further comprising a third light source and a fourth light source that emit ultraviolet light having a second emission peak wavelength different from the first emission peak wavelength, the third light source emits ultraviolet light having an optical axis in a third direction; the fourth light source emits ultraviolet light having an optical axis in a fourth direction different from the third direction, 3. The illumination device according to claim 2, wherein the object includes an area illuminated with both the light from the third light source and the light from the fourth light source, and an area illuminated with only the light from the fourth light source.

9. The illumination device of claim 1 , wherein the first light source and the second light source each include a light emitting diode.

10. the first emission peak wavelength is 360 nm or more and 410 nm or less, The irradiation device according to claim 6 , wherein the second emission peak wavelength is not less than 260 nm and not more than 290 nm.

11. the object moves relative to the irradiation device in a movement direction; The irradiation device according to claim 8 , wherein the first light source and the second light source are disposed upstream of the third light source and the fourth light source in the movement direction.

12. The illumination device according to claim 11 , wherein a distance between the second light source and the third light source in the movement direction is longer than a distance between the first light source and the second light source.

13. a fifth light source and a sixth light source which emit ultraviolet light of a third emission peak wavelength different from both the first emission peak wavelength and the second emission peak wavelength and which have different light distributions from each other, The illumination device according to claim 11 , wherein the fifth light source and the sixth light source are disposed between the first light source and the second light source and the third light source and the fourth light source in the movement direction.

14. The irradiation device according to claim 13 , wherein the third emission peak wavelength is not less than 300 nm and not more than 350 nm.

15. A light emitting device mounted in an illumination device that illuminates an object with light, a first light source and a second light source that emit ultraviolet light having different light distributions from each other; A light emitting device, wherein an area irradiated with light from the first light source and an area irradiated with light from the second light source have at least a non-overlapping area.

16. the first light source emits ultraviolet light at a first luminous intensity distribution angle; The light emitting device according to claim 15 , wherein the second light source emits the ultraviolet light at a second light distribution angle that is wider than the first light distribution angle.

17. a third light source and a fourth light source that emit ultraviolet light having different light distributions from each other; the first light source and the second light source emit ultraviolet light having a first emission peak wavelength, the third light source and the fourth light source emit ultraviolet light having a second emission peak wavelength different from the first emission peak wavelength, the third light source emits ultraviolet light at a third luminous intensity distribution angle, the fourth light source emits ultraviolet light at a fourth light distribution angle that is wider than the third light distribution angle, The light emitting device according to claim 16 , wherein the object includes an area irradiated with both the light from the third light source and the light from the fourth light source, and an area irradiated with only the light from the fourth light source.

18. An ultraviolet light irradiation method using an irradiation device, the irradiation device comprising: The first light source and the second light source emit ultraviolet light having a first emission peak wavelength with different light distributions from each other; a third light source and a fourth light source irradiate ultraviolet light having a second emission peak wavelength shorter than the first emission peak wavelength, the second emission peak wavelength and having different light distributions from each other; an ultraviolet light irradiation method, in which the ultraviolet light having the first emission peak wavelength is irradiated onto the object before the ultraviolet light having the second emission peak wavelength is irradiated onto the object;

19. the irradiation device irradiates the ultraviolet light onto an object that moves relatively in a movement direction; The ultraviolet light irradiation method according to claim 18 , wherein the first light source and the second light source are disposed upstream of the third light source and the fourth light source in the movement direction.

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