JP7653602B2 - Lighting equipment - Google Patents

Description

This disclosure relates to a lighting device.

Patent document 1 discloses a spotlight that includes a plurality of LED modules, each of which includes at least two LEDs having different emission spectra (R, G, R, B), and a plurality of light mixing sections, each of which is arranged to cooperate with an LED module on one side thereof and has a rectangular exit surface from which a light beam is emitted.

Special table 2012-516011 publication

In the lighting device used as a spotlight in the above-mentioned conventional technology, the light emission position of each LED differs with respect to the entrance surface of the light mixing section, so the light distribution of the light beam emitted from the exit surface of the light mixing section differs slightly for each emission spectrum (R, G, R, B). This causes the problem that color unevenness occurs when the light beam is irradiated onto the irradiation surface.

Therefore, the objective of this disclosure is to provide a lighting device that can suppress color unevenness in the light irradiated onto the illumination surface.

In order to achieve the above object, an illumination device according to one aspect of the present disclosure includes a light guide having a plurality of light-emitting units each emitting light of a plurality of colors, and a plurality of light-guiding rods corresponding to the plurality of light-emitting units, the light guide being constituted by the plurality of light-guiding rods each having an incident surface into which light emitted by a corresponding light-emitting unit is incident and an exit surface from which the light incident from the incident surface is exited, a projection optical unit that collects and irradiates the light emitted from the exit surface, and a projection optical unit that is shaped like a bottomed cylinder having light-blocking properties and supports the plurality of light-emitting units and the light guide such that the incident surface of the light guide faces the projection optical unit, and a housing that accommodates the multiple light-emitting units, the light guide, and the projection optical unit in this order by supporting the light guide and the projection optical unit so that the optical body faces the optical body, the housing has a large diameter portion that accommodates the projection optical unit, and a small diameter portion that is smaller in diameter than the large diameter portion and accommodates the light guide and the multiple light-emitting units, the multiple light-emitting units each having one or more light-emitting units with a different sequence of colors of light emitted , the light guide is directly supported by the small diameter portion, and the multiple light-guiding rods are arranged in one-to-one correspondence with the multiple light-emitting units and have a frustum shape that becomes thicker from the small diameter portion toward the large diameter portion .

The lighting device disclosed herein can reduce color unevenness in the light irradiated onto the illumination surface.

FIG. 1 is a diagram illustrating an illumination device according to an embodiment. FIG. 2 is a perspective view illustrating a light guide and a light emitting module of the lighting device according to the embodiment. FIG. 3 is a diagram illustrating an example of an arrangement of light emitting modules with respect to a light guide according to the embodiment, and a diagram illustrating a side surface of the light guide and the light emitting modules. FIG. 4 is a diagram illustrating another arrangement of light emitting modules with respect to a light guide of an illumination device according to an embodiment, and a diagram illustrating a side surface of the light guide and the light emitting modules. FIG. 5A is a diagram illustrating an illumination device according to an embodiment. FIG. 5B is a perspective view illustrating another light guide and a light emitting module of the lighting device according to the first modification of the embodiment. FIG. 6 is a diagram illustrating still another arrangement of light emitting modules with respect to a light guide according to the first modification of the embodiment, and a diagram illustrating a side surface of the light guide and the light emitting modules. Figure 7 is a diagram illustrating yet another arrangement of a light-emitting module relative to a light guide in accordance with variant example 2 of the embodiment, a diagram illustrating the attitude of the light-emitting module relative to the first light-guiding rod and the second light-guiding rod, and a diagram illustrating the side of the light guide and the light-emitting module. Figure 8 is a diagram illustrating yet another arrangement of a light-emitting module relative to a light guide in accordance with the third embodiment, a diagram illustrating the attitude of the light-emitting module relative to the first light-guiding rod and the second light-guiding rod, and a diagram illustrating the side of the light guide and the light-emitting module. FIG. 9 is a perspective view illustrating a light guide of an illumination device according to an embodiment. Figure 10 is a diagram illustrating yet another arrangement of a light-emitting module relative to a light guide in an embodiment, a diagram illustrating the attitude of the light-emitting module relative to the first light-guiding rod and the second light-guiding rod, and a diagram illustrating the side of the light guide and the light-emitting module. FIG. 11 is a diagram illustrating a first emission surface of a light guide according to the embodiment. FIG. 12 is a diagram illustrating an exit surface and an enlarged exit surface of a light guide, and a diagram illustrating a cross section of the light guide taken along line XIIb-XIIb. FIG. 13 is a diagram illustrating the light distribution on the exit surface of the light guide.

Below, the embodiments of the present disclosure will be described with reference to the drawings. Each of the embodiments described below shows a specific example of the present disclosure. Therefore, the numerical values, shapes, materials, components, arrangement positions and connection forms of the components shown in the following embodiments are merely examples and are not intended to limit the present disclosure. Therefore, among the components in the following embodiments, components that are not described in the independent claims will be described as optional components.

Note that each figure is a schematic diagram and is not necessarily a precise illustration. In addition, in each figure, the same reference numerals are used for substantially the same configurations, and duplicate explanations are omitted or simplified.

In the following embodiments, expressions such as "approximately parallel" are used. For example, "approximately parallel" does not only mean "parallel," but also means "substantially parallel," that is, including an error of, for example, about a few percent. Furthermore, "approximately parallel" means "parallel" within the range in which the effects of the present disclosure can be achieved. The same applies to other expressions using "approximately."

In the following description, in FIG. 1, the direction in which the light guide is disposed relative to the light source is referred to as the positive Z-axis direction, and the opposite direction is referred to as the negative Z-axis direction. The same applies to FIG. 2 and subsequent figures.

The following describes the lighting device according to the embodiment of the present disclosure.

(Embodiment)
<Configuration: Illumination device 1>
FIG. 1 is a diagram illustrating an illumination device 1 according to an embodiment.

As shown in FIG. 1, the lighting device 1 is a lighting fixture that uses a cylindrical light guide 30, and is, for example, a spotlight that is placed on a building material such as a ceiling or a wall. The cylindrical shape mentioned here includes not only a cylinder but also a polygonal prism. The lighting device 1 of this embodiment may be placed on a table such as a desk. The lighting device 1 can illuminate a space by irradiating light to the surroundings. The lighting device 1 of this embodiment illuminates the surroundings mainly by emitting light in the positive direction of the Z axis of the long light guide 30.

The lighting device 1 comprises a housing 10, a light-emitting module 20, and a light guide 30.

[Housing 10]
The housing 10 is a bottomed cylinder, and houses the light emitting module 20 and the light guide 30 in the internal space 11. The edge of one end of the housing 10 on the positive Z-axis direction side is open, and the edge of the other end on the negative Z-axis direction side is closed. In the present embodiment, the housing 10 is cylindrical, but may be a polygonal tube or the like. The shape of the housing 10 may be appropriately set according to the cross-sectional shape of the light guide 30 cut on a plane perpendicular to the length direction (Z-axis direction) of the light guide 30. The length direction of the light guide 30 is parallel to the Z-axis direction.

The housing 10 has light-blocking properties. In other words, the housing 10 is configured so that light does not leak to the outside from any location other than the desired location. The housing 10 may have a reflective surface formed on the inner surface thereof that can guide the light emitted by the light-emitting module 20 to the first incident surface 31 of the light guide 30. The inner surface of the housing 10 may be mirror-finished in order to guide the light emitted by the light-emitting module 20 to the light guide 30. The housing 10 may be made of, for example, a metal such as aluminum, a white resin, or the like.

The housing 10 supports the light emitting module 20, which is disposed at the bottom, which is the edge on the negative side of the Z axis, so as to face the light guide 30. Specifically, the housing 10 supports the light emitting module 20 and the light guide 30 so that the first incident surface 31 of the light guide 30 and the light emitting module 20 face each other. The light emitting module 20 and the light guide 30 are arranged in the internal space 11 of the housing 10, housed in that order.

[Light-emitting module 20]
FIG. 2 is a perspective view illustrating the light guide 30 of the lighting device 1 according to the embodiment.

As shown in Figs. 1 and 2, the light-emitting module 20 is housed in the housing 10 and is disposed at the bottom of the housing 10. The light-emitting module 20 is held at the bottom of the housing 10 in a position in which it emits light toward the light guide 30. The light-emitting module 20 is an example of a light-emitting unit.

The light-emitting module 20 has a substrate 21 and one or more light sources 22.

The substrate 21 is a mounting substrate having a mounting surface for mounting one or more light sources 22. In this embodiment, the substrate 21 is formed in a substantially circular plate shape. The substrate 21 is fixed to the mounting surface at the bottom of the housing 10 by a fixing member such as a screw. As the substrate 21, for example, a metal-based substrate obtained by applying an insulating coating to a base material made of a metal material such as aluminum or copper, a ceramic substrate which is a sintered body of a ceramic material such as alumina, or a resin substrate based on a resin material is used. The substrate 21 may be a printed wiring board, a rigid board, or a flexible board.

Each of the one or more light sources 22 is arranged such that the light emitting surface of the light source 22 faces the first incident surface 31 of the light guide 30 and the optical axis of the light source 22 intersects with the first incident surface 31 of the light guide 30. In this embodiment, each of the one or more light sources 22 is arranged inside the housing 10 such that the optical axis is approximately parallel to the central axis of the lighting device 1. Here, the optical axis is a straight line that is approximately coincident with the main emission direction of the light emitted by the light source 22 and is approximately parallel to the Z-axis direction.

Each of the one or more light sources 22 has a light-emitting element that is an LED chip, and a phosphor that emits fluorescent light by wavelength conversion of the light emitted by the light-emitting element. For example, each of the one or more light sources 22 is configured to emit white light. Specifically, each of the one or more light sources 22 is composed of a COB (Chip On Board) type LED (Light Emitting Diode) element, and has LEDs that are bare chips (LED chips) mounted on the substrate 21, and a sealing member that seals the LEDs and contains a phosphor. Note that each of the one or more light sources 22 may be an SMD (Surface Mount Device) type LED.

In this embodiment, multiple light sources 22 are arranged for one light guiding rod 40. The configuration of multiple light sources 22 is shown in Figures 3 and 4.

Fig. 3a is a diagram illustrating the arrangement of the light emitting module 20 relative to the light guide 30 according to the embodiment, and Fig. 3b is a diagram illustrating the side of the light guide 30 and the light emitting module 20. Fig. 4a is a diagram illustrating another arrangement of the light emitting module 20 relative to the light guide 30 of the lighting device 1 according to the embodiment, and Fig. 4b is a diagram illustrating the side of the light guide 30 and the light emitting module 20.

In this embodiment, as shown in FIG. 3A and FIG. 3B, one light emitting module 20 capable of emitting light of different colors is provided so as to face the first main surface 41 of one light guiding rod 40. The light emitting module 20 has a plurality of light sources 22 that emit light of at least a plurality of colors. In the example of FIG. 3A, the light emitting module 20 has four light sources 22 for one light guiding rod 40. In other words, in the light emitting module 20, a plurality of light sources 22 that emit light of different colors are packaged together. One light emitting module 20 can emit four monochromatic lights of red light R, green light G, blue light B, and white light W. The light emitting module 20 emits light of different colors, which are mixed in one light guiding rod 40 to emit white light.

3A, the light emitting modules 20 are arranged in one-to-one correspondence with the light guiding rods 40 constituting the light guide 30. Specifically, the light emitting surface of each of the light emitting modules 20 faces the first main surface 41 of each of the light guiding rods 40 in a one-to-one correspondence. Each of the light emitting modules 20 is arranged to overlap with the first main surface 41 when viewed along the length of the light guiding rod 40 so that the light emitted by the light emitting module 20 is incident on the corresponding first main surface 41. Note that only one light emitting module 20 may be provided for each of the light guiding rods 40. In this case, the light emitted by the light emitting module 20 may be incident on the first main surface 41 of each of the light guiding rods 40.

In addition, in this embodiment, as shown in Fig. 4a and Fig. 4b, a plurality of light emitting modules 20a capable of emitting light of different colors may be provided so as to face the first main surface 41 of one light guiding rod 40. In the example of Fig. 4a, four light emitting modules 20a may be provided for one light guiding rod 40. The four light emitting modules 20a are four-color LED modules of RGBW, and emit four monochromatic lights of red light R, green light G, blue light B, and white light W. The four light emitting modules 20a each emit light of a different color, which is mixed in one light guiding rod 40 to emit white light.

In the example of FIG. 4a, when four light-emitting modules 20a are one module group 20a1, the multiple module groups 20a1 are arranged to correspond one-to-one with the multiple light-guiding rods 40 that constitute the light guide 30. Specifically, the light-emitting surface of each of the multiple module groups 20a1 is arranged to face the first main surface 41 of the multiple light-guiding rods 40 in a one-to-one manner for each module group 20a1. In this case, the module group 20a1 also has multiple light-emitting modules 20a that emit light of at least multiple colors, that is, multiple light sources 22. Note that only one module group 20a1 may be provided for the multiple light-guiding rods 40. In this case, the light emitted by the module group 20a1 may be incident on the first main surface 41 of each of the multiple light-guiding rods 40. The module group 20a1 is a light-emitting unit.

Note that each of the multiple light-emitting modules 20 and each of the multiple module groups 20a1 may be three colors, RGB, or two colors, BW. In other words, the light incident on the first main surface 41 of the light-guiding rod 40 only needs to be of two or more types, and is not limited to four colors. Therefore, as long as each of the multiple light-emitting modules 20 and each of the multiple module groups 20a1 emits light of two or more different colors, there are no limitations on the colors.

The light-emitting module 20 is electrically connected to a power supply circuit and is supplied with power from the power supply circuit. The lighting device 1 may also include a power supply circuit. The light-emitting module 20 may be turned on and off by being controlled by a control unit (not shown) provided in the power supply circuit. The light-emitting module 20 may be dimmed and toned by being controlled by a control unit provided in the power supply circuit.

[Light guide 30]
As shown in FIG. 1 and FIG. 2, the light guide 30 is a light guide that guides the light emitted from the light emitting module 20 and forms a light guide path for emitting the light to the outside of the housing 10. The light guide 30 is a columnar light-transmitting member that is elongated in the Z-axis direction. The light guide 30 does not need to be elongated, and may be a cylindrical columnar light guide 30. In this embodiment, the light guide 30 is a light guide 30 that has a circular or polygonal shape when cut on a plane perpendicular to the length direction. When the cross section of the light guide 30 is polygonal when cut on a plane perpendicular to the length direction, the cross section may be, for example, a polygon with four or six or more sides. When the cross section of the light guide 30 is polygonal, the cross section of the light guide 30 when cut on a plane perpendicular to the length direction may be, for example, a polygon with four or more sides and a multiple of two, three, five, or the like.

The light guide 30 is housed in the housing 10 and is arranged opposite the light emitting module 20, and is supported by the housing 10 at a predetermined distance from the light emitting surfaces of the multiple light sources 22. The light guide 30 is also supported by the housing 10 so that movement in a direction perpendicular to the Z-axis direction is suppressed. The light guide 30 is arranged between the opening of the housing 10 and each of the multiple light sources 22.

The light guide 30 is made of a translucent resin such as silicone resin, acrylic resin, polycarbonate, etc., or a translucent material such as glass.

The light guide 30 has a first entrance surface 31 onto which the light emitted by the light source 22 enters, and a first exit surface 32 from which the light incident from the first entrance surface 31 exits.

The first incident surface 31 is a surface into which light emitted from each of the multiple light sources 22 enters, and is a surface facing the light-emitting surfaces of each of the multiple light sources 22. In other words, the first incident surface 31 is an end surface on the negative Z-axis side of the light guide 30. The first incident surface 31 is approximately perpendicular to the length direction of the light guide 30. The normal to the first incident surface 31 approximately coincides with the optical axis of each of the multiple light sources 22. The first incident surface 31 is an example of an incident surface.

The first exit surface 32 faces the first entrance surface 31 (it is the surface opposite to the first entrance surface 31) and emits light that is incident from the first entrance surface 31 and transmitted through the interior. The first exit surface 32 is the surface from which light that has been guided through the light guide 30 exits. In other words, the first exit surface 32 is the end surface of the light guide 30 on the positive side of the Z axis. The first exit surface 32 is approximately perpendicular to the length direction of the light guide 30. The normal to the first exit surface 32 approximately coincides with the optical axis of each of the multiple light sources 22. The first exit surface 32 is an example of an exit surface.

The shape of the first entrance surface 31 of the light guide 30 is circular or a polygon with four or more sides, and the shape of the first exit surface 32 of the light guide 30 is also circular or a polygon with four or more sides.

The light guide 30 has a plurality of light guide rods 40. In this embodiment, the light guide 30 is configured by bundling a plurality of light guide rods 40 that correspond to the plurality of light emitting modules 20, respectively.

Each of the light guide rods 40 is a columnar member having a first main surface 41 that constitutes a part of the first entrance surface 31 of the light guide 30 and a second main surface 42 that constitutes a part of the first exit surface 32 of the light guide 30. Each of the light guide rods 40 is arranged at a predetermined distance from each of the light sources 22. Specifically, the light guide rods 40 are supported by the housing 10 in a bundled state, and are arranged at a predetermined distance from each of the light emitting surfaces of the light sources 22 so as to face the light emitting surfaces of each of the light sources 22. The first main surface 41 is an example of an entrance surface. The second main surface 42 is an example of an exit surface.

The cross-sectional area of each of the light guiding rods 40, when cut in a plane perpendicular to the length of the light guiding body 30, gradually increases from the first entrance surface 31 to the first exit surface 32 of the light guiding body 30. That is, each of the light guiding rods 40 has a frustum shape that becomes thicker toward the positive Z-axis direction. In other words, each of the light guiding rods 40 has a light guiding joint 35 for joining each of the light guiding rods 40 on the first exit surface 32 side, and a frustum-shaped frustum portion 36 extending in the Z-axis direction from the light guiding joint 35. The light guiding rods 140 of this embodiment all have the same shape.

In addition, on the first entrance surface 31 side of the light guide 30, the multiple light guide rods 40 are spaced apart so that a portion of each is in a non-contact state. In other words, on the first entrance surface 31 side of the light guide 30, the multiple light guide rods 40 are arranged with a gap between them. In this embodiment, such a light guide 30 has multiple light guide rods 40 joined on the first exit surface 32 side of the light guide 30. Note that each of the multiple light guide rods 40 may be supported by simply wrapping a band around the periphery of the side of the light guide 30 on the first exit surface 32 side.

In addition, in the multiple light guiding rods 40, the difference between the maximum area of the multiple first main surfaces 41 and the minimum area of the multiple first main surfaces 41 may be 10% or less of the maximum area. The area of the first main surface 41 of each of the multiple light guiding rods 40 is smaller than the area of the second main surface 42. In this case, the average brightness of the light emitted from each of the second main surfaces 42 of the multiple light guiding rods 40 can be matched, so that the brightness distribution of the irradiation pattern V2 on the irradiation surface V1 can be made approximately uniform.

Multiple light-guiding rods 40 may be joined by being molded integrally, or may be joined by simply bundling each of the individual rods together.

The first main surface 41 of each of the multiple light guiding rods 40 is a surface into which light emitted from each of the multiple light emitting modules 20 enters, and is a surface that faces each of the light emitting surfaces of the multiple light emitting modules 20 in a one-to-one relationship. In other words, the first main surface 41 of each of the multiple light guiding rods 40 constitutes the end surface (first entrance surface 31) of the light guide 30 on the negative Z-axis direction side. The first main surface 41 of each of the multiple light guiding rods 40 is approximately perpendicular to the length direction of the light guide 30. The normal to the center of the first main surface 41 approximately coincides with the central axis of the multiple light emitting modules 20.

When viewed along the length direction of each of the multiple light guiding rods 40, the first main surface 41 of each of the multiple light guiding rods 40 covers the entirety of each of the multiple light guiding modules 20. In other words, when viewed along the length direction, the first main surface 41 of each of the multiple light guiding rods 40 overlaps with the light emitting surface of each of the multiple light guiding modules 20 and covers the entirety of the light emitting surface of each of the multiple light guiding modules 20. For this reason, the width (length in the direction perpendicular to the Z-axis direction) of the first main surface 41 of each of the multiple light guiding rods 40 is greater than the width of the light emitting surface of each of the multiple light guiding modules 20.

The second main surface 42 of each of the light guiding rods 40 faces the first main surface 41 of each of the light guiding rods 40 (the surface opposite to the first main surface 41 of each of the light guiding rods 40), and emits light incident from the first main surface 41. The second main surface 42 of each of the light guiding rods 40 is a surface from which light guided through each of the light guiding rods 40 exits. In other words, the second main surface 42 of each of the light guiding rods 40 constitutes the end surface (first exit surface 32) on the Z-axis positive side of the light guiding body 30. The second main surface 42 of each of the light guiding rods 40 is approximately perpendicular to the length direction of the light guiding body 30. The normal to the center of each of the second main surfaces 42 of the light guiding rods 40 approximately coincides with the central axis of each of the light emitting modules 20.

As a result, the center of gravity of the contours on the first main surface 41 of each of the multiple light-guiding rods 40 is included in the central axis of each of the multiple light-emitting modules 20. In other words, the center of gravity of the contours on each of the first main surfaces 41 corresponds one-to-one with the central axis of each of the multiple light-emitting modules 20.

As shown in Figures 1 and 2, the outer shape of the first exit surface 32 of the light guide 30 is circular or polygonal. In addition, the outer shapes of the first main surfaces 41 and second main surfaces 42 of the multiple light guide rods 40 that constitute the first entrance surface 31 and first exit surface 32 of the light guide 30 are circular or polygonal.

[Arrangement of the light emitting module 20 relative to the light guide 30]
In the present embodiment, there are a plurality of arrangements of the colors of light emitted by each of the plurality of light-emitting modules 20 for each of the plurality of light-guiding rods 40. In other words, the plurality of light-emitting modules 20 includes one or more light-emitting modules 20 each having a different arrangement of the colors of light emitted by each of the plurality of light-emitting modules 20. In the present embodiment, one or more of the plurality of light-emitting modules 20 are rotated and arranged so as to be different from the arrangement of the colors of light emitted by each of the other light-emitting modules 20 among the plurality of light-emitting modules 20.

For example, in an example in which one light-emitting module 20 has multiple light sources 22, as in FIG. 3A, at least one of the multiple light-emitting modules 20 has a different arrangement (disposition) of the colors of the light emitted. In other words, at least one of the multiple light-emitting modules 20 has a different arrangement of the colors of the light emitted by each of the multiple light sources 22 of the light-emitting module 20 from the other light-emitting modules 20.

In this embodiment, the multiple light-emitting modules 20 are arranged so that the sequence of the colors of light they emit is all different. Figures 2 and 3a show an example in which each of the multiple light sources 22 in one light-emitting module 20 emits light of a different color, and therefore the differences in the colors are indicated by hatching. The same applies to Figures 4 and onwards.

The arrangement of the light colors will be specifically described with reference to FIG. 3a. In the light-emitting module 20 at the top left of the drawing, the central axis O of the light-guiding rod 40, the X direction including the central axis O, and the Y direction perpendicular to the X direction and including the central axis O are defined. In the X direction, the right side of the drawing relative to the central axis O is the positive side, and the left side is the negative side, and in the Y direction, the upper side of the drawing relative to the central axis O is the positive side, and the lower side is the negative side. In this case, in the light-emitting module 20 at the top left of the drawing, the light source 22 that emits red light is arranged on the positive side in the X direction and the negative side in the Y direction, the light source 22 that emits green light is arranged on the positive side in the X direction and the positive side in the Y direction, the light source 22 that emits blue light is arranged on the negative side in the X direction and the negative side in the Y direction, and the light source 22 that emits white light is arranged on the negative side in the X direction and the positive side in the Y direction. The other light-emitting modules 20 are arranged so that the arrangement of the colors of the light they emit is different from that of the light-emitting module 20 at the top left of the drawing.

In this embodiment, the light-emitting module 20 is rotated in position, but a light-emitting module 20 in which the arrangement of the multiple light sources 22 is different may be used as a method for varying the arrangement of the colors of light emitted.

In addition, for example, in an example in which four light-emitting modules 20a are grouped into one module group 20a1 as in FIG. 4a, at least one of the multiple module groups 20a1 has a different sequence of colors of light emitted toward the multiple light-guiding rods 40. In other words, the sequence of colors of light emitted by the light sources 22 of at least one of the multiple module groups 20a1 is different from that of the other module groups 20a1.

In FIG. 4a, two of the four module groups 20a1 have a different arrangement of the colors of light emitted by the light source 22 than the other two module groups 20a1.

In this case, a method for varying the arrangement of the emitted light colors may be used in which the light-emitting modules 20a have different arrangements of the multiple light sources 22.

<Operation>
In such lighting device 1, the light emitted from light source 22 is incident on each of first main surfaces 41 of the plurality of light guiding rods 40 constituting first entrance surface 31 of light guide 30, and is guided through each of the plurality of light guiding rods 40. The light emitted from light source 22 is reflected by the side surface of light guiding rod 40, and mixed when being guided through light guiding rod 40.

Light incident on the first main surface 41 of each of the multiple light guiding rods 40 constituting the light guide 30 is guided through each of the multiple light guiding rods 40 to reach the second main surface 42, and is emitted from each second main surface 42, i.e., the first emission surface 32 of the light guide 30. At least one of the multiple light guiding rods 40 emits light with a different color sequence, so that when light is emitted from the light guide 30, color unevenness in the light irradiated to the irradiation surface V1 can be suppressed. In this lighting device 1, the surroundings can be illuminated by emitting light from the light guide 30, which has the function of emitting light.

<Action and effect>
Next, the effects of the lighting device 1 according to the present embodiment will be described.

As described above, the lighting device 1 of this embodiment includes a plurality of light-emitting units (light-emitting modules 20, module group 20a1) each emitting light of a plurality of colors, and a light guide 30 having a plurality of light-guiding rods 40 corresponding to each of the plurality of light-emitting units, the light guide 30 being composed of light-guiding rods 40 having an incident surface (first main surface 41) into which light emitted by the corresponding light-emitting unit is incident, and an exit surface (second main surface 42) from which the light incident from the incident surface exits. The plurality of light-emitting units each include one or more light-emitting units that emit light with a different sequence of colors.

For example, the arrangement of the light sources emitting red light, green light, and blue light in the light-emitting unit will be slightly different with respect to the incident surface of the light guide. Therefore, if the sequence of colors of light emitted by each of the multiple light-emitting units is the same, as in conventional lighting devices, the light incident on the light guide will also be the same for each light-emitting unit, which can result in color unevenness in the light emitted from the light guide.

However, according to this embodiment, multiple light emitting elements can cause light with different color sequences to be incident on the entrance surfaces of multiple light guiding rods 40. When light is guided through each of the multiple light guiding rods 40, the light with different color sequences is mixed and emitted from the exit surfaces of the multiple light guiding rods 40, so the light guide 30 can emit averaged light, that is, light with reduced color unevenness.

Therefore, this lighting device 1 can suppress color unevenness in the light irradiated onto the irradiation surface V1.

In addition, in the lighting device 1 of this embodiment, one or more of the multiple light-emitting units are rotated and arranged so that the sequence of the colors of light emitted by each of the other light-emitting units of the multiple light-emitting units is different.

With this, even if the same light emitting unit is used, multiple light emitting units can easily make light with different color arrangements enter the entrance surfaces of multiple light guiding rods 40. Therefore, when light is guided through each of the multiple light guiding rods 40, light of different colors is mixed, so that light with reduced color unevenness can be emitted from the exit surfaces of the multiple light guiding rods 40.

Furthermore, by simply rotating the light-emitting unit, i.e., by changing the position of the light-emitting unit, it is possible to easily suppress uneven coloring of the light irradiated onto the irradiation surface V1. Therefore, compared to the case where different light-emitting units are used, it is possible to suppress an increase in the manufacturing costs of the lighting device 1.

In addition, for example, if each of the multiple light-emitting units has multiple light sources 22, it is possible to prevent the light-emitting unit from becoming too large.

In addition, in the lighting device 1 of this embodiment, the multiple light-emitting elements are rotated and arranged at equal intervals relative to the light guide 30 so that the sequence of the colors of light emitted by each of the multiple light-emitting elements is different.

By using the same light emitting section, light with different color arrangements from the multiple light emitting sections can be made to enter the entrance surfaces of the multiple light guiding rods 40. Therefore, when light is guided through each of the multiple light guiding rods 40, light of more different colors is mixed, so that light with less color unevenness can be emitted from the exit surfaces of the multiple light guiding rods 40.

In addition, in the lighting device 1 of this embodiment, the multiple light-emitting sections are provided in one-to-one correspondence with the multiple light-guiding rods 40. When viewed along the longitudinal direction of each of the multiple light-guiding rods 40, the incident surface of each of the multiple light-guiding rods 40 covers the entirety of each of the multiple light-emitting sections.

This allows the light emitted by the light-emitting unit to be incident on the light-guiding rod 40, thereby preventing a decrease in optical performance.

(First Modification of the Embodiment)
A lighting device 1a according to this modified example will be described with reference to FIGS. 5A, 5B, and 6. FIG.

Figure 5A is a diagram illustrating a lighting device 1a according to an embodiment. Figure 5B is a perspective view illustrating another light guide 130 and light emitting module 20 of lighting device 1a according to modified example 1 of the embodiment. Figure 6a is a diagram illustrating yet another arrangement of light emitting module 20 relative to light guide 130 according to modified example 1 of the embodiment, and Figure 6b is a diagram illustrating a side view of light guide 130 and light emitting module 20.

As shown in Figures 5A, 5B, and 6, this modified example differs from the embodiment in that the light guide 130 has a polygonal shape when cut along a plane perpendicular to the length of the light guide 130. The configuration of the lighting device 1a of this modified example is similar to that of the lighting device of the embodiment, and the same components are denoted by the same reference numerals and detailed description of the configuration is omitted.

In this modified example, as shown in Figures 5A and 5B, the lighting device 1a is a lighting fixture that uses a cylindrical light guide 130 and a projection optical body 50.

The lighting device 1a includes a housing 10, a light-emitting module 20, a light guide 130, and a projection optical body 50.

The housing 10 is a cylindrical body with a bottom, and houses the light emitting module 20, the light guide 130, and the projection optical body 50 in the internal space 11. The light emitting module 20, the light guide 130, and the projection optical body 50 are arranged in this order in the internal space 11 of the housing 10.

The housing 10 supports the light guide 130 and the projection optical body 50 so that the first exit surface 32 of the light guide 130 and the second entrance surface 51 of the projection optical body 50 face each other, and the focal point of the projection optical body 50 is located on the first exit surface 32 of the light guide 130. The housing 10 holds the projection optical body 50 against the light guide 130 in order to emit narrow-angle light from the lighting device 1.

As shown in Figures 5A and 5B, the projection optical body 50 collects and irradiates the light emitted from the second emission surface 52. Specifically, the projection optical body 50 is a light distribution control member for emitting light at a predetermined light distribution angle after the light emitted by the light emitting module 20 and guided through the light guide 130 is guided inside the projection optical body 50. The projection optical body 50 is a lens that is flat in the Z-axis direction. In this embodiment, the projection optical body 50 is a one-sided convex lens, but it may also be a two-sided convex lens, one-sided concave lens, or two-sided concave lens.

The first incident surface 31 of the light guide 130 is disposed at a position that substantially coincides with the focal point of the projection optical body 50. Specifically, the second main surface 42 of the light guide rod 40 that is disposed at the center of the light guide 130 among the multiple light guide rods 40 is disposed at a position that substantially coincides with the focal point of the projection optical body 50, and more preferably, the center point of the second main surface 42 is disposed.

The projection optical body 50 is housed in the housing 10. The projection optical body 50 is arranged on the optical path of the light emitted from the light guide 130, and can control the distribution of the light emitted by the light guide 130 to irradiate the light of the circular irradiation pattern V2 on the irradiation surface V1. The projection optical body 50 is supported by the housing 10 so that movement in a direction perpendicular to the Z-axis direction is suppressed. The projection optical body 50 may be appropriately replaced depending on the size, shape, etc. of the light guide 130. When the projection optical body 50 is supported by the housing 10, the central axis of the projection optical body 50 is approximately aligned with the central axis of the light guide 130.

The projection optical body 50 is made of a translucent resin such as silicone resin or acrylic resin, or a translucent material such as glass. In this embodiment, acrylic resin is used for the projection optical body 50.

The projection optical body 50 has a second entrance surface 51 and a second exit surface 52.

The second entrance surface 51 is the surface on which the light emitted from the first exit surface 32 of the light guide 130 enters. The second entrance surface 51 is the surface on which the light emitted from each of the multiple light emitting modules 20 and guided through the light guide 130 enters, and is the surface opposite the first exit surface 32 of the light guide 130. In other words, the second entrance surface 51 is the surface on the negative Z-axis direction side of the projection optical body 50.

When viewed along the alignment direction of the light guide 130 and the projection optical body 50, the second entrance surface 51 covers the entire first exit surface 32 of the light guide 130. In other words, when viewed along the alignment direction, the second entrance surface 51 overlaps with the first exit surface 32 of the light guide 130 and covers the entire first exit surface 32.

The second exit surface 52 is a surface facing the second entrance surface 51 (a surface on the opposite side of the second entrance surface 51) and emits light incident from the second entrance surface 51. The light emitted from the second exit surface 52 illuminates the irradiation surface V1.

In the projection optical body 50, the light emitted from the first exit surface 32 of the light guide 30 is incident on the second entrance surface 51 of the projection optical body 50. The light incident on the second entrance surface 51 is subjected to light distribution control as it passes through the projection optical body 50, and is emitted from the second exit surface 52 of the projection optical body 50.

In this modification, the light guide 130 has a rectangular shape, which is an example of a polygonal shape, when cut in a plane perpendicular to the length direction. Note that the cross section of the light guide 130 when cut in a plane perpendicular to the length direction may be a polygon with four or six or more sides, for example. In this modification, the shape of the first entrance surface 31 of the light guide 130 is a polygon with four sides, and the shape of the first exit surface 32 of the light guide 130 is also a polygon with four sides.

In addition, the multiple light guide rods 140 are joined together without gaps on the first emission surface 32 side of the light guide 130. Therefore, the first emission surface 32 of the light guide 130 is a flat surface that does not have gaps or recesses.

The first main surface 41 of each of the multiple light guiding rods 140 may be a flat surface that does not have gaps or recesses on the first incident surface 31 by bundling the multiple light guiding rods 140 together. In this case, on the first incident surface 31 side of the light guide 130, each of the multiple light guiding rods 140 is joined without gaps.

In addition, on the first incident surface 31 side of the light guide 130, the multiple light guide rods 140 are spaced apart so that they are not in contact with each other. This allows the weight of the light guide 130 to be reduced compared to a light guide 130 with narrow gaps. This prevents the material cost of the light guide 130 from rising, thereby preventing the cost of the lighting device 1a from rising.

In addition, the second main surface 42 of each of the multiple light guiding rods 140 forms a plane that does not form gaps or recesses in the first emission surface 32 by bundling the multiple light guiding rods 140 together. In other words, the first emission surface 32 of the light guide 130 is such that each of the multiple light guiding rods 140 is joined without gaps or recesses.

The multiple light emitting modules 20 are rotated and arranged at equal intervals relative to the multiple light guides 130 so that the color of light emitted by each of the multiple light emitting modules 20 is arranged in a different order.

For example, as shown in FIG. 6A, the light-emitting modules 20 are rotated at equal intervals so that the arrangement of the colors of light emitted by each of the light-emitting modules 20 differs for each light-emitting module 20. In FIG. 6A, the light-emitting modules 20 are rotated every 90°.

The effects of this modified example are similar to those of the embodiment described above.

(Second Modification of the Embodiment)
A lighting device 1b according to this modified example will be described with reference to FIG.

Figure 7a illustrates another arrangement of the light emitting module 20 relative to the light guide 230 according to the second modified embodiment, Figure 7b illustrates the position of the light emitting module 20 relative to the first light guide rod 40a and the second light guide rod 40b, and Figure 7c illustrates the side of the light guide 230 and the light emitting module 20.

As shown in FIG. 7, this modified example differs from the embodiment in that the light guide 230 has a cylindrical shape. The configuration of the lighting device 1b of this modified example is similar to the configuration of the lighting device of the embodiment, and the same components are denoted by the same reference numerals and detailed description of the configuration is omitted.

In this modification, the light guide 230 has one or more first light guide rods 40a having a first shape and a plurality of second light guide rods 40b having a second shape that is different from the first shape. In this modification, the light guide 230 is composed of the first light guide rod 40a arranged in the center of the light guide 230 and a plurality of second light guide rods 40b arranged around the first light guide rod 40a, parallel to the length direction of the first light guide rod 40a. In other words, the plurality of second light guide rods 40b are arranged concentrically around the first light guide rod 40a, so as to surround the periphery of the first light guide rod 40a.

In this modified example, the first exit surface 32 and the first entrance surface 31 of the light guide 230 have a circular outer shape.

For example, if the cross section of the light guide 230 is circular when cut in a plane perpendicular to the length direction, the cross section of the first light guide rod 40a when cut in a plane perpendicular to the length direction is circular or polygonal, which are examples of the first shape, and the cross section of the second light guide rod 40b when cut in a plane perpendicular to the length direction is circular or polygonal, which are examples of the second shape.

In addition, when the cross section of the light guide 230 is polygonal when cut in a plane perpendicular to the length direction, the cross section of the first light guide rod 40a is circular or polygonal, and the cross section of the second light guide rod 40b is sector-shaped, i.e., polygonal, when cut in a plane perpendicular to the length direction. In FIG. 7A, the cross section of the first light guide rod 40a is circular, and the cross section of the second light guide rod 40b is sector-shaped. In addition, the outer shapes of the first main surface 41a and the second main surface 42a of the first light guide rod 40a are circular or polygonal, and the outer shapes of the first main surface 41b and the second main surface 42b of the second light guide rod 40b are circular or polygonal.

In this modified example, the polygonal shape is not limited to shapes with all straight sides, but also includes shapes with one or more arc-shaped sides.

The cross-sectional shape of the first light guiding rod 40a when cut along a plane perpendicular to the longitudinal direction and the cross-sectional shape of the second light guiding rod 40b when cut along a plane perpendicular to the longitudinal direction may be the same or different.

One or more first light guide rods 40a and multiple second light guide rods 40b are bundled together so that the outer shape of the first light exit surface 32 of the light guide 230 is a circle without a recess. A circle without a recess means a circle that is substantially free of recesses.

As shown in Fig. 7a and Fig. 7b, there are multiple arrangements of the colors of light emitted by each of the multiple light-emitting modules 20. One or more of the multiple light-emitting modules 20 are rotated and arranged so as to be different from the arrangement of the colors of light emitted by each of the other light-emitting modules 20 among the multiple light-emitting modules 20.

In this modification, the multiple light-emitting modules 20 are arranged so that the sequence of the colors of the light they emit is all different. This illustrates a case in which the multiple light sources 22 of one light-emitting module 20 emit light of different colors. Specifically, in all of the light-emitting modules 20 corresponding to the first light-guiding rod 40a and the multiple second light-guiding rods 40b, the multiple light-emitting modules 20 are arranged at equal intervals so that the sequence of the colors of the light emitted by the multiple light sources 22 is different for each light-emitting module 20. In this modification, the multiple light-emitting modules 20 are arranged at equal intervals by rotating an angle obtained by dividing 360° by the number of light-emitting modules 20. In this modification, the light-emitting modules 20 are rotated by 51.4° each.

In addition, in this modified example, the multiple light emitting modules 20 can be said to be arranged at equal intervals and rotated with respect to the multiple second light guiding rods 40b within one group formed of multiple second light guiding rods 40b of the same shape so that the sequence of the colors of light emitted by at least the multiple light emitting modules 20 is different. In other words, in the multiple second light guiding rods 40b arranged on the same circumference, each of the light emitting modules 20 facing the multiple second light guiding rods 40b is rotated with equal intervals and arranged in a one-to-one relationship with each of the multiple second light guiding rods 40b.

The multiple light emitting modules 20 are arranged concentrically to correspond to the first main surface 41a and the first main surface 41b of the first light guiding rod 40a and the multiple second light guiding rods 40b, respectively. In this modified example, the multiple light emitting modules 20 are arranged concentrically around the light emitting module 20 corresponding to the first light guiding rod 40a, surrounded by the remaining multiple light emitting modules 20 that correspond one-to-one to the multiple second light guiding rods 40b.

The same is true in an example in which four light-emitting modules 20 are grouped into one module group 20a1, as shown in FIG. 4a.

In this manner, in the lighting device 1c of this modified example, the light guide 230 has one or more first light guide rods 40a having a first shape and a plurality of second light guide rods 40b having a second shape that is different from the first shape. The plurality of light emitting units are rotated at equal intervals relative to the plurality of second light guiding rods 40b within one group formed of the plurality of second light guiding rods 40b of the same shape so that the sequence of the colors of light emitted by each of the plurality of light emitting units is different.

This allows the mixed light to be emitted from the light guiding rod 40 arranged in the light guiding body 230, and also from the second light guiding rod 40b arranged around the first light guiding rod 40a. Therefore, light with reduced color unevenness can be emitted from the respective emission surfaces (second main surface 42a, second main surface 42b) of the first light guiding rod 40a and the second light guiding rod 40b.

The effects of this modified example are similar to those of the embodiment described above.

(Third Modification of the Embodiment)
A lighting device 1c according to this modified example will be described with reference to FIG.

Figure 8a illustrates another arrangement of the light emitting module 20 relative to the light guide 330 according to the third modified embodiment, Figure 8b illustrates the position of the light emitting module 20 relative to the first light guide rod 40a and the second light guide rod 40b, and Figure 8c illustrates the side of the light guide 330 and the light emitting module 20.

As shown in FIG. 8, this modified example differs from the modified example 2 of the embodiment in that the light-emitting modules 20 are rotated and arranged at equal intervals for each group unit according to the shape of the light-guiding rod. The configuration of the lighting device 1c of this modified example is similar to the configuration of the lighting device of the modified example 2 of the embodiment, and the same components are denoted by the same reference numerals and detailed description of the configuration is omitted.

In this modified example, the light guide 330 has one or more first light guide rods 40a having a first shape and a plurality of second light guide rods 40b having a second shape.

As shown in Fig. 8a and Fig. 8b, there are multiple arrangements of the colors of light emitted by each of the multiple light-emitting modules 20. One or more of the multiple light-emitting modules 20 are rotated and arranged so as to be different from the arrangement of the colors of light emitted by each of the other light-emitting modules 20 of the multiple light-emitting modules 20.

The light emitting modules 20 are arranged at equal intervals in rotation so that they correspond one-to-one with the second light guiding rods 40b arranged on the same circumference among the second light guiding rods 40b, so that the arrangement of the colors of light emitted by each of the light emitting modules 20 is different. The light emitting modules 20 are arranged concentrically so as to correspond to the first main surface 41a and the first main surface 41b of one or more first light guiding rods 40a and the second light guiding rods 40b. In this modified example, the light emitting modules 20 are arranged concentrically so that the light emitting module 20 corresponding to the first light guiding rod 40a is at the center and is surrounded by the remaining light emitting modules 20 corresponding one-to-one with the second light guiding rods 40b.

In this modified example, the posture of the first light-emitting module 20c1, which is the light-emitting module 20 corresponding to the first light-guiding rod 40a, is the same as the posture of one of the second light-emitting modules 20c2, which is the light-emitting module 20 corresponding to each of the second light-guiding rods 40b. The first light-emitting module 20c1 and the second light-emitting module 20c2 are examples of light-emitting units.

The second light-emitting modules 20c2 are arranged so that the color arrangement of the light emitted by each of them is different. Figures 8a and 8b show an example in which each of the light sources 22 in one second light-emitting module 20c2 emits light of a different color. Specifically, in all of the second light-emitting modules 20c2, each of the second light-emitting modules 20c2 is rotated at equal intervals so that the color arrangement of the light emitted by each of the light sources 22 in each second light-emitting module 20c2 is different. In this modification, each of the second light-emitting modules 20c2 is rotated at equal intervals by an angle obtained by dividing 360° by the number of second light-emitting modules 20c2. In this modification, the second light-emitting modules 20c2 are rotated by 60° each.

8a, the cross-sectional shape of the light guide 330 cut along a plane perpendicular to the length of the light guide 330 is circular, but as shown in Figs. 9 and 10, the cross-sectional shape of the light guide 330a may be polygonal. Fig. 9 is a perspective view illustrating the light guide 330a of the lighting device 1c according to the embodiment. Fig. 10a is a diagram illustrating yet another arrangement of the light emitting module 20 relative to the light guide 330a according to the embodiment, Fig. 10b is a diagram illustrating the posture of the light emitting module 20 relative to the first light guiding rod 40a and the second light guiding rod 40b, and Fig. 10c is a diagram illustrating the side of the light guide 330a and the light emitting module 20. In FIG. 10, the outer shape of the first emission surface 32 of the light guide 330a is polygonal (e.g., hexagonal to dodecagonal), and the outer shape of the second main surface 42a of the first light guide rod 40a is a polygon with six sides. The outer shape of the second main surface 42b of the second light guide rod 40b is sector-shaped, that is, polygonal (e.g., quadrangle or pentagon).

Although Fig. 8, Fig. 9, and Fig. 10 illustrate the case where there is one first light guide rod 40a, as shown in Fig. 11, multiple first light guide rods 40a may be provided. Fig. 11 illustrates the first emission surface 32 of the light guide body 330b according to the embodiment.

In the light guide 330b of this modification, as shown by the dashed line in FIG. 11, a plurality of first light guide rods 40a are provided at the center of the light guide 330b. As described above, the first main surface 41a and the second main surface 42a of the first light guide rod 40a have a polygonal or circular outer shape. The shape of the second main surface 42a of the first light guide rod 40a of this modification is hexagonal, but is not limited to a hexagon. In this modification, the shapes of the second main surfaces 42a are the same, but are not limited to this. For example, two types of first light guide rods 40a with different shapes of the second main surfaces 42a may be used.

The second light guide rods 40b are arranged parallel to the length direction of the first light guide rod 40a group, which is made up of the first light guide rods 40a bundled together, and surround the first light guide rods 40a group. As described above, the first main surface 41b and the second main surface 42b of the second light guide rod 40b are polygonal in shape.

In this modified example, the first light guide rods 40a are grouped into a first group indicated by a dashed line and arranged in the center of the light guide 330, and the second light guide rods 40b are grouped into a second pentagonal group indicated by a dashed line and a third hexagonal group indicated by a dashed line. In other words, the first light guide rods 40a and the second light guide rods 40b are grouped according to the cross-sectional shape of the same shape.

In all of the second light-emitting modules 20c2, which are the light-emitting modules 20 corresponding to the first light-guiding rod 40a of the first group, the second light-emitting modules 20c2 are rotated at equal intervals so that the arrangement of the colors of the light emitted by each of the light sources 22 differs for each second light-emitting module 20c2. In all of the third light-emitting modules 20c3, which are the light-emitting modules 20 corresponding to the second light-guiding rod 40b of the second group, the third light-emitting modules 20c3 are rotated at equal intervals so that the arrangement of the colors of the light emitted by each of the light sources 22 differs for each third light-emitting module 20c3. In all of the fourth light-emitting modules 20c4, which are the light-emitting modules 20 corresponding to the second light-guiding rod 40b of the third group, the fourth light-emitting modules 20c4 are rotated at equal intervals so that the arrangement of the colors of the light emitted by each of the light sources 22 differs for each fourth light-emitting module 20c4. The third light-emitting module 20c3 and the fourth light-emitting module 20c4 are examples of a light-emitting unit.

In this modified example, each of the second light-emitting modules 20c2 is rotated at equal intervals by an angle obtained by dividing 360° by the number of second light-emitting modules 20c2. In this modified example, the second light-emitting modules 20c2 are rotated by 51.4°. Each of the third light-emitting modules 20c3 is rotated at equal intervals by an angle obtained by dividing 360° by the number of third light-emitting modules 20c3. In this modified example, the third light-emitting modules 20c3 are rotated by 60°. Each of the fourth light-emitting modules 20c4 is rotated at equal intervals by an angle obtained by dividing 360° by the number of fourth light-emitting modules 20c4. In this modified example, the fourth light-emitting modules 20c4 are rotated by 60°.

In this modification, the cross-sectional shapes of the first light guiding rod 40a and the second light guiding rod 40b are exemplified as pentagonal and hexagonal, but are not limited to pentagonal and hexagonal. The cross-sectional shapes of the first light guiding rod 40a and the second light guiding rod 40b may be other polygonal shapes. In addition, in this modification, two or more types of second light guiding rods 40b whose second main surface 42a has a pentagonal and hexagonal shape are used, but this is not limited to this, and three or more different types of second light guiding rods 40b may be used.

The cross-sectional shape of the first light guiding rod 40a when cut along a plane perpendicular to the longitudinal direction of the first light guiding rod 40a may be a polygon with 10 or less sides. In particular, it is preferable that the cross-sectional shape of the first light guiding rod 40a when cut along a plane perpendicular to the longitudinal direction of the first light guiding rod 40a is a regular polygon with 3, 4, or 6 sides.

The same applies to an example in which four light-emitting modules 20 are grouped into one module group, as shown in FIG. 4A.

In the lighting device 1c of this modified example, the light guide bodies 330, 330a, and 330b have one or more first light guide rods 40a having a first shape and a plurality of second light guide rods 40b having a second shape. The plurality of second light guide rods 40b are arranged concentrically around the one or more first light guide rods 40a as the center so as to surround the periphery of the one or more first light guide rods 40a. The plurality of light emitting units are arranged concentrically so as to correspond to the first main surfaces 41a and the first main surfaces 41b of the one or more first light guide rods 40a and the plurality of second light guide rods 40b. The plurality of light emitting units are arranged at equal intervals in a rotational relationship with each of the plurality of second light guiding rods 40b arranged on the same circumference among the plurality of second light guiding rods 40b so that the arrangement of the colors of light emitted by each of the plurality of light emitting units is different.

This allows mixed light to be emitted from the first light guiding rod 40a arranged in the light guiding bodies 330, 330a, 330b, and also allows mixed light to be emitted from the multiple second light guiding rods 40b arranged around the first light guiding rod 40a. Therefore, light with reduced color unevenness can be emitted from the second main surfaces 42a and 42b of the multiple first light guiding rods 40a and the multiple second light guiding rods 40b.

The effects of this modified example are similar to those of the embodiment described above.

(Other Modifications)
Although the lighting device according to the present disclosure has been described based on the embodiments, the present disclosure is not limited to the above-described embodiments.

For example, in the lighting device according to the above embodiment, as shown in FIG. 12, the first exit surface 332 of the light guide 330 may be a scattering surface that scatters the emitted light. In this way, the first exit surface 332 of the light guide 330 can emit light with reduced color and brightness unevenness. FIG. 12 is a diagram illustrating the first exit surface 332 of the light guide 330 and an enlarged view of the first exit surface 332, and a diagram illustrating a cross section of the light guide 330 taken along line XIIb-XIIb.

In addition, in the lighting device according to the above embodiment, the first exit surface 332 of the light guide 330 may have a plurality of dimple shapes or uneven shapes. According to this, the first exit surface 332 of the light guide 330 can emit light with suppressed color unevenness and brightness unevenness. In addition, the spread angle of the light distribution from the first exit surface 332 can be controlled by the dimple shape or uneven shape formed on the first exit surface 332. The spread angle of the light distribution from the first exit surface 332 is shown in FIG. 13. FIG. 13 is a diagram illustrating the light distribution distribution of the first exit surface 332 in the light guide 330. When the first exit surface 332 of the light guide 330 does not have a dimple shape or uneven shape, that is, when the first exit surface 332 of the light guide 330 is a flat surface, it can be seen that unevenness occurs in the light distribution distribution from the first exit surface 332 of the light guide 330, as shown in FIG. 13. However, when a dimple shape or unevenness is formed on the first exit surface 332 of the light guide 330, as shown in FIG. 13, it can be seen that unevenness in the light distribution from the first exit surface 332 of the light guide 330 is suppressed.

In addition, in the light guide of the lighting device according to the above embodiment, one light emitting section may correspond to two or more light guiding rods, in which case the light emitting section may cause light to enter two or more light guiding rods.

This disclosure also includes forms obtained by applying various modifications to the above-described embodiments that would come to mind by a person skilled in the art, and forms realized by arbitrarily combining the components and functions of each embodiment without departing from the spirit of this disclosure.

1, 1a, 1b, 1c Illumination device 20, 20a Light-emitting module (light-emitting unit)
20a1 Module group (light emitting section)
20c1 First light emitting module (light emitting unit)
20c2 Second light emitting module (light emitting unit)
20c3 Third light emitting module (light emitting unit)
20c4 Fourth light emitting module (light emitting unit)
30, 30a, 30b, 130, 230, 330, 330a, 330b Light guide body 40, 140 Light guide rod 40a First light guide rod 40b Second light guide rod 41, 41a, 41b First main surface (incident surface)
42, 42a, 42b Second main surface (emission surface)

Claims (7)

A plurality of light emitting units each emitting light of a plurality of colors;
a light guide having a plurality of light guide rods corresponding to the plurality of light emitting units, the light guide being configured with the plurality of light guiding rods each having an incident surface into which light emitted by the corresponding light emitting unit is incident and an exit surface from which the light incident from the incident surface is exited;
a projection optical body that collects and irradiates the light emitted from the exit surface;
a housing having a bottomed cylindrical shape having light-shielding properties, supporting the plurality of light-emitting units and the light guide so that the plurality of light-emitting units and the incident surface of the light guide face each other, and supporting the light guide and the projection optical body so that the exit surface of the light guide faces the projection optical body, thereby housing the plurality of light-emitting units, the light guide, and the projection optical body in this order;
the housing has a large diameter portion that houses the projection optical body, and a small diameter portion that is smaller in diameter than the large diameter portion and houses the light guide and the plurality of light emitting portions,
The plurality of light-emitting units each include one or more light-emitting units each having a different sequence of colors of light emitted therefrom ,
The light guide is directly supported by the small diameter portion,
The plurality of light guiding rods include
are arranged in one-to-one correspondence with the plurality of light-emitting units,
The cone-shaped member has a truncated cone shape that becomes thicker from the small diameter portion toward the large diameter portion.
Lighting equipment. The lighting device according to claim 1 , wherein one or more of the plurality of light-emitting sections are rotated and arranged so as to be different from an arrangement of colors of light emitted by each of the other light-emitting sections of the plurality of light-emitting sections. The lighting device according to claim 2 , wherein the plurality of light emitting sections are disposed at equal intervals and rotated with respect to the light guiding body such that an arrangement of colors of light emitted by each of the plurality of light emitting sections differs. the light guide body includes one or more first light guide rods having a first shape and a plurality of second light guide rods having a second shape different from the first shape,
4. The lighting device according to claim 2 or 3, wherein the plurality of light-emitting sections are arranged in a group formed by the plurality of second light-guiding rods of the same shape, rotated at equal intervals relative to the plurality of second light-guiding rods, so that the arrangement of the colors of light emitted by each of the plurality of light-emitting sections is different. the light guide body includes one or more first light guide rods having a first shape and a plurality of second light guide rods having a second shape;
the second light guiding rods are concentrically arranged around the one or more first light guiding rods so as to surround the one or more first light guiding rods;
the plurality of light emitting sections are concentrically arranged to correspond to the entrance surfaces of the one or more first light guiding rods and the plurality of second light guiding rods,
4. The lighting device according to claim 2 or 3, wherein each of the plurality of light-emitting sections is rotated at equal intervals among the plurality of second light-guiding rods arranged on the same circumference so that the sequence of colors of light emitted by each of the plurality of light-emitting sections is different, and each of the plurality of light-emitting sections is rotated at equal intervals among the plurality of second light-guiding rods arranged on the same circumference so that each of the plurality of light-emitting sections corresponds to a respective one of the plurality of second light-guiding rods. The lighting device according to claim 1 , wherein the exit surface of the light guide is a scattering surface that scatters the exiting light. The plurality of light emitting units are provided in one-to-one correspondence with the plurality of light guiding rods,
The lighting device according to any one of claims 1 to 6, wherein when viewed along the longitudinal direction of each of the light guiding rods, the incident surface of each of the light guiding rods covers the entirety of each of the light guiding sections.

Images