JP6598000B2 - Lighting device - Google Patents

Description

  The present invention relates to an illuminating device including an optical member containing a pigment.

  In recent years, the importance of design in industrial products has been increasing, and various designs have been devised in lighting devices. For example, Patent Literature 1 discloses a footlight in which the light source inside the lighting device is not conspicuous when turned off, and the appearance is improved.

JP 2010-277708 A

  By the way, an optical member containing a pigment such as a pigment filter may be used for the purpose of enhancing the color rendering of light emitted from the lighting device. In an illuminating device provided with such an optical member, it is better that the color of the optical member is less visible from the outside in terms of appearance.

  Therefore, the present invention provides an illumination device in which the color of an optical member containing a pigment is difficult to see.

  An illumination device according to one embodiment of the present invention includes a light source and a cover that has a light-transmitting base material and diffuses light from the light source, and the base material absorbs light having a specific wavelength. Dyes to be included.

  ADVANTAGE OF THE INVENTION According to this invention, the illuminating device with which the color of the optical member containing a pigment | dye is hard to see is implement | achieved.

FIG. 1 is an external perspective view of the lighting apparatus according to Embodiment 1. FIG. FIG. 2 is a schematic cross-sectional view of the lighting apparatus according to Embodiment 1. FIG. 3 is an external perspective view of the light emitting module. FIG. 4 is a diagram showing the light transmittance of the cover. FIG. 5 is a schematic diagram illustrating an example of an optical path when the illumination device according to Comparative Example 1 emits light. FIG. 6 is a schematic diagram illustrating an example of an optical path when the lighting apparatus according to Embodiment 1 emits light. FIG. 7 is a diagram illustrating the light emission characteristics of the lighting apparatus according to Embodiment 1 and the pigment content. FIG. 8 is a schematic cross-sectional view of the illumination device according to the second embodiment.

  Hereinafter, embodiments will be specifically described with reference to the drawings. It should be noted that each of the embodiments described below shows a comprehensive or specific example. Numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of the constituent elements, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. In addition, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims indicating the highest concept are described as optional constituent elements.

  Each figure is a schematic diagram and is not necessarily illustrated strictly. Moreover, in each figure, the same code | symbol is attached | subjected to the substantially same structure, and the overlapping description may be abbreviate | omitted or simplified.

(Embodiment 1)
[overall structure]
Hereinafter, the configuration of the lighting apparatus according to Embodiment 1 will be described. FIG. 1 is an external perspective view of the lighting apparatus according to Embodiment 1. FIG. FIG. 2 is a schematic cross-sectional view of the lighting apparatus according to Embodiment 1. 2 is a schematic cross-sectional view when the lighting device according to Embodiment 1 is cut in a plane (ZX plane) perpendicular to the longitudinal direction (Y-axis direction). Note that the sizes of the light diffusing material 61 and the pigment 62 in FIG. 2 are not exactly shown.

  In the following description, the Z axis + side in the figure is expressed as “upper side”, and the Z axis − side in the figure is expressed as “lower side”.

  A lighting device 10 shown in FIG. 1 is a long lighting device attached to a structure such as a wall or a ceiling, and is used for architectural lighting. The illumination device 10 is used for, for example, cove illumination or cornice illumination. The lighting device 10 includes a light emitting module 20, a cover 30, a base 40, and a power supply unit 70. The cover 30 and the base 40 also function as an outer casing that houses the light emitting module 20. Hereinafter, each component will be described in detail.

[Light emitting module]
First, the light emitting module 20 will be described with reference to FIG. 3 in addition to FIGS. FIG. 3 is an external perspective view of the light emitting module 20.

  The light emitting module 20 is an example of a light source, and a plurality of the light emitting modules 20 are arranged along the longitudinal direction. That is, the lighting device 10 includes a plurality of light emitting modules 20.

  As illustrated in FIG. 3, the light emitting module 20 is a surface mount device (SMD) type light emitting module. The light emitting module 20 includes a substrate 21, a plurality of LED elements 22 mounted on the substrate 21 in a line, a wiring 23, a connector 24, and a connector 25.

  The substrate 21 is a long rectangular substrate. The substrate 21 is a resin-based CEM-3 (Composite Epoxy Material-3) substrate, but may be another resin substrate, a metal base substrate, or a ceramic substrate. Examples of other resin substrates include FR-4 (Frame Regentant-4) substrates. Examples of the ceramic substrate include an alumina substrate made of aluminum oxide (alumina) and an aluminum nitride substrate made of aluminum nitride. Examples of the metal base substrate include an aluminum alloy substrate, an iron alloy substrate, and a copper alloy substrate.

  The substrate 21 is screwed to the base 40 so that the longitudinal direction is parallel to the longitudinal direction of the base 40 and the short direction perpendicular to the longitudinal direction is parallel to the short direction of the base 40. In FIG. 3, the screw insertion holes provided in the substrate 21 through which the screws are inserted are not shown.

  The first main surface of the substrate 21 is a main surface (main surface on the Z-axis side) facing the cover 30, and a plurality of LED elements 22 are mounted in a row along the longitudinal direction on the first main surface. Is done. A white resist is provided on the first main surface of the substrate 21. More specifically, the surface of the base material of the substrate 21 is partially covered with a white resist that is a light reflecting member having higher light reflectivity than the surface. In a region where the white resist is not provided on the surface of the substrate 21, the wiring 23 is exposed to mount the LED element 22, the connector 24, and the connector 25.

  A second main surface (a main surface on the Z axis + side) that is the main surface opposite to the first main surface of the substrate 21 is in surface contact with the base 40. Note that a heat radiating member such as heat radiating silicone may be provided between the second main surface of the substrate 21 and the base 40.

  The LED element 22 is a so-called SMD type element and emits white light. The LED element 22 includes a package 22a, an LED chip 22b mounted on the bottom surface of the recess of the package 22a, and a sealing member 22c that fills the recess of the package 22a and seals the LED chip 22b. The LED element 22 includes a metal terminal (not shown) for mounting the LED element 22 on the substrate 21.

  The package 22a is a container molded with a non-translucent resin (white resin or the like), and includes an inverted frustoconical recess (cavity). The inner side surface of the recess is an inclined surface and is configured to reflect light from the LED chip 22b downward (Z-axis direction).

  The LED chip 22b is an example of a light emitting element, and is a bare chip that emits monochromatic visible light. The LED chip 22b is die-bonded to the bottom surface of the recess of the package 22a with a die attach material (die bond material). The LED chip 22b is, for example, a blue LED chip that emits blue light. More specifically, the blue LED chip is a gallium nitride-based semiconductor light-emitting element having a center wavelength of 430 nm or more and 480 nm or less, which is made of an InGaN-based material.

  The sealing member 22c is a translucent resin material including phosphor particles that are wavelength conversion materials, and converts the wavelength of the light from the LED chip 22b and protects the LED chip 22b by sealing the LED chip 22b. To do. The sealing member 22c is filled in the recess of the package 22a, and is sealed up to the opening surface of the recess.

  For example, a silicone resin is used as the translucent resin material, but an epoxy resin or a urea resin may be used. The phosphor particles are, for example, yttrium, aluminum, garnet (YAG) yellow phosphor particles.

  The phosphor particles are excited by the blue light emitted from the LED chip 22b to emit yellow light. For this reason, white light is emitted from the sealing member 22c by mixing the excited yellow light and the blue light emitted from the LED chip 22b. The sealing member 22c may contain a light diffusing material such as silica. Further, the sealing member 22c may include red phosphor particles, green phosphor particles, and the like for the purpose of improving color rendering.

  The wiring 23 is a metal wiring made of tungsten (W) or copper (Cu). The wiring 23 is patterned in a predetermined shape so as to electrically connect the LED elements 22 to each other and to electrically connect the LED elements 22 to the connector 24 and the connector 25. The wiring 23 is patterned so that when the plurality of light emitting modules 20 are physically connected using the connector 24 and the connector 25, the plurality of light emitting modules 20 are electrically connected in parallel.

  The connector 24 and the connector 25 are connectors for electrically connecting one light emitting module 20 to another light emitting module 20. The connector 24 of one light emitting module 20 is electrically connected to the connector 25 of the light emitting module 20 arranged next to the Y-axis direction by a connecting lead wire or the like. Further, the connector 25 of one light emitting module 20 is electrically connected to the connector 24 of the light emitting module 20 disposed adjacent to the Y axis + direction by a connecting lead wire or the like. For example, DC power is supplied from the power supply unit 70 to the connector (connector 24 or connector 25) of the light emitting module 20 located at the end in the Y-axis direction among the plurality of light emitting modules 20. Thereby, the plurality of light emitting modules 20 emit light.

[cover]
The cover 30 is an example of an optical member, and includes a base material 60 having translucency, and diffuses light from the plurality of light emitting modules 20. The cover 30 has a shape in which a part of the long cylinder is cut out along the long length (in the tube axis direction), and is curved so that the apex is located on the lower side. Although not shown in detail, the cover 30 is attached to the base 40 by sliding and inserting an end portion in the short side direction (X-axis direction) into the base 40.

  The base material 60 of the cover 30 is a transparent resin material made of, for example, acrylic resin, and transmits light emitted from the light emitting module 20. That is, the cover 30 has translucency. The cover 30 may be formed of glass or polycarbonate resin.

  Further, the base material 60 of the cover 30 includes a plurality of light diffusing materials 61. The light diffusing material 61 is disposed in a substantially uniform manner in the substrate 60. The light emitted from the light emitting module 20 is diffused (reflected) by the light diffusing material 61 when passing through the cover 30. The light diffusing material 61 is, for example, a silicone resin having a white diameter of about 1 μm, but may be silica or the like. The concentration of the light diffusing material included in the cover 30 is, for example, 0.05 wt% or more and 2.0 wt% or less.

  Note that the cover 30 only needs to have a light diffusing function. For example, the cover 30 is formed with a lens-like structure or a concave or convex portion on at least one of the inner surface and the outer surface, thereby diffusing the light. It may have a function. The cover 30 may have a light diffusion function by printing a dot pattern on at least one of the inner surface and the outer surface of the cover 30, for example.

  The base material 60 of the cover 30 contains a plurality of pigments 62 that absorb light of a specific wavelength. The dye 62 is dispersed and arranged almost uniformly in the substrate 60. Specifically, the dye 62 is a tetraazaporphyrin-based dye containing a metal element such as copper (Cu), nickel (Ni), and cobalt (Co). The cover 30 appears light purple by containing the pigment 62. In Embodiment 1, the dye 62 is a tetraazaporphyrin-based dye containing nickel.

  The specific wavelength is, for example, a wavelength of 585 nm or more and 595 nm or less, and the dye 62 containing nickel mainly absorbs light having a wavelength of 585 nm or more and 595 nm or less. That is, the cover 30 mainly absorbs light having a wavelength of 585 nm or more and 595 nm or less. FIG. 4 is a diagram illustrating the intensity of light transmitted through the cover 30. Note that the vertical axis in FIG. 4 is transmitted through the cover 30 with respect to the intensity of light transmitted through the cover 30 (the cover of the lighting device according to Comparative Example 2 described later) when the pigment 62 is not included. The intensity ratio of the emitted light is shown. That is, the amount of light that is increased or decreased when the cover 30 contains the pigment 62 is shown. The horizontal axis indicates the wavelength of light.

  As shown in FIG. 4, at a wavelength of 585 nm or more and 595 nm or less, the light intensity ratio is 75% or less, and the bottom of the light intensity ratio is about 70%. That is, the cover 30 transmits light having a wavelength of 585 nm or more and 595 nm or less that is reduced by 25% or more (about 30% at the maximum) as compared with the case where the pigment 62 is not included in the cover 30. Due to the characteristics of the cover 30, the average color rendering index Ra of the light emitted from the lighting device 10, an index PS (Preference Index of Skin Color) indicating the preference of skin color, and an index FCI indicating the vividness of the color. (Feeling of Contrast Index) and the like can be improved.

  The cover 30 may include an ultraviolet absorber (UVA), a light stabilizer (HALS), and the like. Further, the cover 30 may include a quencher that suppresses deterioration of the acrylic resin.

[Base and power supply]
The base 40 is a rectangular tubular casing that is long in the Y-axis direction, and houses the power supply unit 70 therein. The base 40 is used for mounting the lighting device 10 to a structure, and also functions as a mounting base for the light emitting module 20 and a heat sink. Specifically, the base 40 is formed of aluminum, but may be formed of iron or aluminum die cast.

  The power supply unit 70 is a power supply circuit that converts AC power supplied to the lighting device 10 into DC power suitable for the light emitting module 20 to emit light and outputs the DC power. Specifically, the power supply unit 70 includes a substrate and circuit components mounted on the substrate. The circuit components include, for example, capacitive elements such as electrolytic capacitors or ceramic capacitors, resistance elements, coil elements, choke coils (choke transformers), noise filters, and semiconductor elements such as diodes or integrated circuit elements.

[Effects]
In the lighting device 10, both the light diffusing material 61 and the pigment 62 are added to the base material 60 of the cover 30. In other words, the cover 30 has both a function as an optical member that diffuses light and a function as a dye filter that absorbs light of a specific wavelength. Hereinafter, effects obtained by such a cover 30 will be described in comparison with Comparative Example 1. FIG. 5 is a schematic diagram illustrating an example of an optical path when the illumination device according to Comparative Example 1 emits light. FIG. 6 is a schematic diagram illustrating an example of an optical path when the illumination device 10 emits light.

  The illuminating device 10a according to Comparative Example 1 shown in FIG. 5 includes a light emitting module 20 held on a base 40a, a dye filter 90, and a diffusion cover 80 disposed between the light emitting module 20 and the dye filter 90. And have.

  The diffusion cover 80 is formed by adding a light diffusion material 61 to an acrylic resin that is a base material. The base material of the diffusion cover 80 does not include the dye 62. The dye filter 90 is formed by adding the dye 62 to an acrylic resin as a base material. The base material of the dye filter 90 does not include the light diffusing material 61. Thus, unlike the lighting device 10, the lighting device 10a includes the diffusion cover 80 and the dye filter 90 as separate components.

  In the illuminating device 10 a according to Comparative Example 1 shown in FIG. 5, the light emitted from the LED element 22 is diffused in the diffusion cover 80 and then passes through the dye filter 90.

  On the other hand, in the illuminating device 10, the light emitted from the LED element 22 is diffused in the cover 30 containing the pigment 62 as the light L <b> 1 illustrated in FIG. 6. For this reason, in the illuminating device 10 which concerns on Embodiment 1, the light emitted from the LED element 22 permeate | transmits the cover 30 and the exterior (space of illumination object) rather than the illuminating device 10a which concerns on the comparative example 1. The number (frequency) of hitting the dye 62 before being emitted increases. Therefore, the specific wavelength component is easily absorbed by the dye 62.

  Similarly, like the light L2 illustrated in FIG. 6, light once incident on the cover 30 and having a specific wavelength component absorbed by the pigment 62 is diffused to the light emitting module 20 side by the light diffusing material 61, and thereafter In some cases, the light is reflected by the light emitting module 20 (or the base 40) and is incident on the cover 30 again. By such multiple reflection, the number of times that the light emitted from the LED element 22 hits the dye 62 in the cover 30 before it passes through the cover 30 and is emitted to the outside increases. Easy to be absorbed.

  Here, as described above, the pigment 62 is used to increase an evaluation index such as the average color rendering index Ra of the light emitted from the lighting device 10. In the case where light having an evaluation index equivalent to that of the lighting device 10a according to the comparative example 1 is emitted from the lighting device 10, since the light hits the pigment 62 in the cover 30 before the light is emitted, the inclusion of the pigment 62 in the cover 30 is included. The rate (content) can be reduced as compared with the dye filter 90. That is, it is possible to make the color of the cover 30 light and make the color difficult to see.

  Hereinafter, such an effect will be described with reference to FIG. FIG. 7 is a diagram showing the light emission characteristics of the light emitted from the illumination device 10 and the pigment content. In FIG. 7, the row of “Comparative Example 2 (no pigment)” shows the illumination device (in which the cover 30 of the illumination device 10 does not contain the pigment 62 and is replaced with a cover containing the light diffusing material 61). Hereinafter, the characteristics of the illumination device according to Comparative Example 2 are also shown. In FIG. 7, Tc means correlated color temperature, and Duv means chromaticity deviation.

  As shown in FIG. 7, the lighting device 10 has Ra, PS, and FCI improved compared to the lighting device according to Comparative Example 2 because the base material 60 of the cover 30 contains the pigment 62. . For example, Ra is improved from 82.4 to 91.2, PS is improved from 89.6 to 93.3, and FCI is improved from 111.0 to 122.0. In addition, Tc of the illuminating device 10 is 2784K (Kelvin), and Tc of the illuminating device according to Comparative Example 2 is 2727K. Duv is from -0.41 to -2.80.

  On the other hand, the illuminating device 10a according to Comparative Example 1 also has better characteristics than the illuminating device according to Comparative Example 2 by including the dye filter 90. For example, Ra is 89.4, PS is 93.0, and FCI is 119.8. The Tc of the lighting device according to Comparative Example 1 is 2780K. Duv is -2.07.

  Here, the illumination device 10 and the illumination device 10a according to Comparative Example 1 are greatly different in the content ratio of the pigment 62. Although the content rate of the pigment | dye 62 of the cover 30 (base material 60) is 2.3 ppm, the content rate of the pigment | dye 62 of the pigment | dye filter 90 is 15 ppm, and is 6 times or more of the illuminating device 10. FIG. That is, the color of the cover 30 is much lighter than the color of the dye filter 90.

  As described above, the lighting device 10 includes the light-emitting module 20 and the base material 60 having translucency, and includes the cover 30 that diffuses light from the light-emitting module 20. A dye that absorbs light of a wavelength is included.

  Thereby, the light emitted from the light emitting module 20 (LED element 22) is diffused in the cover 30, and the number of times the light hits the pigment 62 in the cover 30 before passing through the cover 30 and being emitted to the outside increases. . For this reason, the color of the cover 30 can be reduced by reducing the content of the pigment 62.

(Embodiment 2)
A high refractive index material having a higher light refractive index than the base material 60 may be further provided on the outer surface of the cover 30. Further, a low reflection material having a light reflectance lower than that of the base material 60 may be further provided on the inner surface of the cover 30. Hereinafter, the lighting apparatus according to the second embodiment will be described. FIG. 8 is a schematic cross-sectional view of the illumination device according to the second embodiment. Note that in the following second embodiment, components that are substantially the same as those of the lighting device 10 are denoted by the same reference numerals, and description thereof may be omitted.

  As illustrated in FIG. 8, the illumination device 110 according to Embodiment 2 includes a light emitting module 20, a cover 30, a base 40, and a power supply unit 70. Here, in the illumination device 110, the high refractive index material 31 is provided on almost the entire outer surface of the cover 30, and the low reflection material 32 is provided on almost the entire inner surface of the cover 30. The outer surface of the cover 30 is a surface opposite to the light emitting module 20 and is a surface not facing the light emitting module 20. The inner surface of the cover 30 is a surface facing the light emitting module 20.

  The high refractive index material 31 is formed of a material having a higher light refractive index than the base material 60. As described above, when the base material 60 is an acrylic resin, the high refractive index material 31 is formed of, for example, a polycarbonate resin. The refractive index of the acrylic resin is 1.49 to 1.53, and the refractive index of the polycarbonate resin is 1.58 to 1.60. In addition, the high refractive index material should just have a refractive index higher than the base material 60, and has translucency. When the base material 60 is a material other than the acrylic resin, the high refractive index material 31 may be, for example, a transparent silicone resin.

  Since the high refractive index material is provided on the outer surface of the cover 30 in this manner, external light is likely to be totally reflected at the interface between the cover 30 and the high refractive index material 31, and therefore enters the cover 30 when the lighting device 110 is turned off. The amount of external light to be reduced can be reduced. Therefore, it is difficult to see the color of the cover 30 (color of the pigment 62) when the light is turned off, and deterioration of the appearance when the light is turned off can be suppressed.

  The low reflective material 32 is formed of a material having a lower reflectance than the base material 60. Specifically, the low reflection material 32 is an AR (Anti Reflection) film or the like.

  By providing the low reflective material 32 in this way, the amount of light incident on the cover 30 when the lighting device 110 is turned on can be increased, and the light extraction efficiency can be increased.

(Summary)
As described above, the illuminating device 10 (or the illuminating device 110) includes the light emitting module 20 and the base member 60 having translucency, and includes the cover 30 that diffuses the light from the light emitting module 20. Includes a dye 62 that absorbs light of a specific wavelength.

  Thereby, the light emitted from the light emitting module 20 is diffused in the cover 30, and the number of times the light hits the pigment 62 in the cover 30 before passing through the cover 30 and being emitted to the outside increases. For this reason, the color of the cover 30 can be reduced by reducing the content of the pigment 62.

  Further, the cover 30 diffuses light from the light emitting module 20 by including the light diffusing material 61 in the base material 60, and the concentration of the light diffusing material 61 included in the base material 60 is 0.05 wt% or more. It may be 0 wt% or less.

  Thus, as the cover 30, for example, a cover whose concentration of the light diffusing material 61 included in the substrate 60 is 0.05 wt% or more and 2.0 wt% or less can be adopted.

  Further, like the lighting device 110, a high refractive index material 31 having a light refractive index higher than that of the base material 60 may be further provided on the outer surface of the cover 30 opposite to the light emitting module 20.

  Thereby, since the external light is easily totally reflected at the interface between the cover 30 and the high refractive index material 31, the amount of the external light incident on the cover 30 when the lighting device 110 is turned off can be reduced. Therefore, it is difficult to see the color of the cover 30 (color of the pigment 62) when the light is turned off, and deterioration of the appearance when the light is turned off can be suppressed.

  Further, like the lighting device 110, a low reflection material 32 having a light reflectance lower than that of the base material 60 may be further provided on the inner surface of the cover 30 facing the light emitting module 20.

  Thereby, the light quantity which injects into the cover 30 at the time of lighting of the illuminating device 110 can be increased, and the extraction efficiency of light can be improved.

  The dye 62 absorbs light having a wavelength of 585 nm or more and 595 nm or less, and the cover 30 reduces light having a wavelength of 585 nm or more and 595 nm or less by 25% or more than when the cover 30 does not include the dye 62. It may be permeated.

  Thereby, the average color rendering index Ra, the index PS indicating the preference of skin color, the index FCI indicating the vividness of the color, and the like of the light emitted from the lighting device 10 (or the lighting device 110) can be improved. .

  The dye 62 may be a tetraazaporphyrin-based dye containing nickel.

  Thus, as the dye 62, a tetraazaporphyrin-based dye containing nickel can be employed.

(Other embodiments)
Although the embodiment has been described above, the present invention is not limited to such an embodiment.

  For example, in the said embodiment, the illuminating device was demonstrated as architecture lighting. However, the present invention can be applied to other lighting devices as long as the lighting device includes a light source such as the light emitting module and a cover that diffuses and transmits light from the light source. Specifically, the present invention can also be applied to ceiling lights, straight tube lamps, base lights, and the like.

  The mode of the light source is not limited to the SMD type light emitting module as described above. For example, a light emitting module having a COB (Chip On Board) structure may be used as the light source. In a light emitting module having a COB structure, an LED chip is directly mounted on a substrate, and the LED chip is sealed with a translucent resin material containing phosphor particles. Further, a remote phosphor type light emitting module having an LED chip and a resin member including phosphor particles arranged at a position away from the LED chip may be used as a light source.

  Moreover, in the said embodiment, although the LED chip was used for the light emitting module as a light emitting element, solid state light emitting elements, such as semiconductor light emitting elements, such as a semiconductor laser, organic EL (Electro Luminescence), or inorganic EL, are used as a light emitting element. May be used.

  In addition, one or a plurality of modes may be used in the present embodiment in which various modifications conceived by those skilled in the art have been made in this embodiment, or in a configuration constructed by combining components in different embodiments, without departing from the spirit of the present invention. It may be included in the range.

10, 10a, 110 Lighting device 20 Light emitting module (light source)
30 Cover 31 High Refractive Index Material 32 Low Reflective Material 61 Light Diffusing Material 62 Dye

Claims (6)

A light source;
Comprising a base material having translucency, comprising a cover for diffusing light from the light source,
The substrate includes a dye that absorbs light of a specific wavelength,
Wherein the base material, wherein the outer surface of the light source and the opposite side, the lighting apparatus high refractive index material having a higher refractive index of light than the substrate is further provided. The cover diffuses light from the light source by including a light diffusing material in the base material,
The lighting device according to claim 1, wherein a concentration of the light diffusing material included in the base material is 0.05 wt% or more and 2.0 wt% or less. The lighting device according to claim 1, wherein a low-reflecting material having a light reflectance lower than that of the base material is further provided on an inner surface of the cover facing the light source. The dye absorbs light having a wavelength of 585 nm or more and 595 nm or less,
The illuminating device according to any one of claims 1 to 3, wherein the cover transmits light having a wavelength of 585 nm or more and 595 nm or less reduced by 25% or more than when the cover does not contain the pigment. The lighting device according to claim 4, wherein the pigment is a tetraazaporphyrin pigment containing nickel. The lighting device according to claim 1, wherein a thickness of the high refractive index material is thinner than a thickness of the cover.

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