JP6210414B2 - lighting equipment - Google Patents

Description

  The present invention relates to a lighting fixture, and more particularly, to an edge-lighting lighting fixture in which light from a light source is incident on a side surface of a light guide plate and is emitted from a main surface of the light guide plate.

  2. Description of the Related Art Conventionally, there is known an edge-light type lighting fixture in which light from a light source is incident on a side surface of a light guide plate and is emitted from a main surface (light emission surface) of the light guide plate (see, for example, Patent Documents 1 to 3) .

JP 2008-311091 A Japanese Patent No. 5022118 JP 2013-127854 A

  Such an edge light type lighting fixture has an advantage that it is easy to reduce the thickness because the light source is disposed on the side of the light guide plate. On the other hand, normally, no light is emitted from the side of the light guide plate (behind the light source).

  Therefore, the present invention provides an edge light type lighting apparatus that can emit light also from the side of a light guide plate.

  In order to solve the above-described problem, a lighting fixture according to one embodiment of the present invention includes a light source that emits light forward, a first main surface, and a part of the light emitted from the light source. A light guide plate that guides light to the main surface side, a main body portion that opposes the first main surface, a peripheral portion that surrounds at least a part of a side surface of the light guide plate, and a cover having translucency, A reflection portion provided as a part of the light guide plate or provided between a side surface of the light guide plate and the peripheral portion of the cover, and the light source emits light toward the side surface of the light guide plate. It is arrange | positioned between the said peripheral part of the said cover, and the side surface of the said light-guide plate so that it may radiate | emit, and the said reflection part reflects the other part of the light which the said light source emits toward the back of the said light source.

  Further, for example, there may be a plurality of light sources, and the plurality of light sources may be arranged at positions that do not face each other with the light guide plate interposed therebetween.

  In addition, for example, a concave portion that is recessed toward the inside of the light guide plate is provided on a side surface of the light guide plate, the light source emits light toward a bottom surface of the concave portion, and the reflection portion includes an inner portion of the recess. It may be a side surface.

  Further, for example, the reflection portion may be provided at an end portion in the thickness direction of the side surface of the light guide plate.

  Further, for example, a convex portion protruding toward the outside of the light guide plate may be provided on a side surface of the light guide plate, and the reflective portion may be a side surface of the convex portion.

  For example, the reflective surface of the reflective portion may be stepped.

  For example, the reflective surface which the said reflection part has does not need to be orthogonal to the straight line parallel to the optical axis of the said light source.

  In addition, for example, a first plate-like portion that is directly overlapped with a second main surface that is a main surface opposite to the first main surface of the light guide plate, or that is overlapped via another member; A substrate having a second plate-like portion positioned between a side surface of the light guide plate and the peripheral portion of the cover, and the reflecting portion is a surface of the second plate-like portion facing the light source. It may be.

  In addition, for example, the substrate further includes a third plate-like portion positioned between a side surface of the light guide plate and the peripheral edge portion of the cover, and the light source includes the light guide among the third plate-like portions. You may provide in the surface facing the side surface of an optical plate.

  Further, for example, a part of the light emitted from the light source is incident on a light incident part of the side surface of the light guide plate, and the light incident part mainly includes a part of the light emitted from the light source inside the light guide plate. The reflection unit may reflect the other part of the light emitted from the light source mainly toward the rear of the light source.

  For example, the reflection unit may reflect another part of the light emitted from the light source toward the peripheral portion of the cover located behind the light source.

  ADVANTAGE OF THE INVENTION According to this invention, the lighting fixture of the edge light system which can be made to radiate | emit light also from the side of a light-guide plate is implement | achieved.

FIG. 1 is a schematic cross-sectional view showing a configuration of an edge light type downlight. FIG. 2 is a schematic diagram showing a configuration of a downlight intended for general household use. FIG. 3 is a diagram illustrating an appearance of the lighting apparatus according to Embodiment 1. FIG. 4 is a schematic cross-sectional view of the lighting apparatus according to Embodiment 1. FIG. 5 is a diagram for explaining the positional relationship between the light source and the light guide plate. FIG. 6 is a diagram illustrating another aspect of the reflecting section according to the first embodiment. FIG. 7 is a diagram illustrating a reflection portion provided as a separate body from the light guide plate. FIG. 8 is a view for explaining a reflection portion formed by bending a plate-like member. FIG. 9 is a schematic cross-sectional view of a lighting fixture according to Embodiment 2. FIG. 10 is an enlarged view of the reflecting section according to the second embodiment. FIG. 11 is a diagram illustrating another aspect of the reflecting section according to the second embodiment. FIG. 12 is a diagram illustrating an example in which a reflection portion is provided on a light guide plate having a polygonal shape in plan view. FIG. 13 is a diagram illustrating a reflection portion provided as a separate body from the light guide plate having a polygonal shape in plan view. FIG. 14 is a diagram for explaining the positional relationship between a light guide plate having a polygonal shape in plan view and a light source.

(Knowledge that became the basis of the present invention)
Conventionally, an edge-light type lighting fixture is known. FIG. 1 is a schematic cross-sectional view showing a configuration of an edge light type downlight.

  As shown in FIG. 1, the luminaire 50 a is an edge light type downlight and is embedded in the ceiling material 60. The light source 10 a is disposed on the side of the light guide plate 25 in the housing 55 and emits light toward the side surface of the light guide plate 25.

  A large number of grooves and dot patterns are formed on the surface (second main surface 25 b) opposite to the light exit surface (first main surface 25 a) of the light guide plate 25. Further, the reflection sheet 40 is superimposed on the second main surface 25 b of the light guide plate 25.

  Therefore, the light incident on the light guide plate 25 is mainly reflected by the second main surface 25b and emitted from the first main surface 25a. The light emitted from the light guide plate 25 is emitted indoors through the cover 35.

  By the way, there is an increasing number of cases where lighting fixtures embedded in the ceiling, such as downlights, are used as indoor lighting in ordinary households. In such a case, in order to brighten the room as uniformly as possible, it is desirable to have a lighting fixture configured to distribute light also to the ceiling surface and wall surface. FIG. 2 is a schematic diagram showing a configuration of a downlight intended for general household use.

  Assuming general household use, as shown in FIG. 2, it is conceivable that the light emitting portion of the luminaire 50 b protrudes from the ceiling material 60 to the indoor side. Thereby, the light of the lighting fixture 50b is distributed also to a ceiling surface or a wall surface.

  When the light emitting portion of the lighting fixture 50b is projected to the indoor side, it is assumed that the cover 30 is provided with a peripheral edge portion 30b that faces the side surface of the light guide plate 25. Here, light is emitted from the main body 30a of the cover 30 facing the first main surface 25a, but no light is normally emitted from the peripheral edge 30b of the cover 30.

  Therefore, in the configuration such as the lighting fixture 50b, it is a problem that light is emitted also from the peripheral portion 30b (side of the light guide plate 25) of the cover 30 and the entire light emitting portion protruding from the ceiling surface emits light uniformly. It becomes. However, it is not easy to emit light from the peripheral portion 30b (the rear side of the light source 10) of the cover 30 because the light source 10 itself becomes an obstacle and blocks light.

  The present invention has been made by the inventors in view of such a situation.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  Note that each of the embodiments described below shows a specific example of the present invention. The numerical values, shapes, materials, constituent elements, arrangement positions and connection forms of the constituent elements, steps, order of steps, 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 exactly. Therefore, there is a portion that does not exactly match in each figure.

(Embodiment 1)
First, the whole structure of the lighting fixture which concerns on Embodiment 1 is demonstrated. FIG. 3 is a diagram illustrating an appearance of the lighting apparatus according to Embodiment 1. FIG. 4 is a schematic cross-sectional view of the lighting apparatus according to Embodiment 1. 4 shows only one light source (only the light source 10), the luminaire 100 includes a plurality of light sources including the light source 10. The content described as the light source 10 in the following description is the same for each light source included in the lighting fixture 100.

  As shown in FIGS. 3 and 4, the luminaire 100 includes a light source 10, a light guide plate 20, a cover 30 (a main body 30 a and a peripheral edge 30 b), a reflection sheet 40, a substrate 70, and a mounting spring. A spring 75, a power supply unit 80, and a heat sink 90 are provided.

  The luminaire 100 is an edge light type downlight that is fixed to the ceiling member 60 by a mounting spring 75. As shown in FIG. 4, the luminaire 100 is partially embedded in the ceiling, and in a state of being fixed to the ceiling member 60, only the cover 30 is visible from the room.

  The luminaire 100 is characterized in that the entire cover 30 emits light substantially uniformly. That is, the luminaire 100 is characterized in that the peripheral portion 30 b of the cover 30 emits light in the same manner as the main body portion 30 a of the cover 30. Hereinafter, each structure of the lighting fixture 100 is demonstrated.

  The heat sink 90 is a heat sink made of aluminum die casting, and is a member for radiating heat generated by light emission of the light source 10. The heat sink 90 also functions as a housing that houses the power supply unit 80. The heat sink 90 may be formed of a material other than aluminum die casting.

  The power supply unit 80 is a power supply circuit that supplies power for the light source 10 to emit light. Although not shown in FIGS. 3 and 4, the downlight may be separately provided with a housing for storing the power supply circuit.

  The substrate 70 is an aluminum substrate, and is mounted between the substrate body 70a (first plate-shaped portion) and the peripheral portion 30b of the cover 30 and the side surface of the light guide plate 20 that extends from the substrate body 70a. 70b (third plate-like portion). The light source 10 is mounted on the surface of the mounting portion 70b that faces the side surface of the light guide plate 20. The substrate 70 may be formed of a material other than aluminum.

  Note that the mounting portion 70 b does not cover the entire circumference of the side surface of the light guide plate 20, and a plurality of mounting portions 70 b are provided corresponding to the position of the light source 10. Here, it is desirable that the mounting portion 70b be formed as small as possible within a range in which the light source 10 can be mounted so as not to block light traveling toward the peripheral portion 30b. That is, the size of the mounting portion 70b when viewed from the side is preferably as small as possible.

  The cover 30 includes a main body portion 30a facing the first main surface 20c of the light guide plate 20, and a translucent portion 30b extending from the main body portion 30a and surrounding at least a part of the side surface of the light guide plate 20. Is an optical member. The cover 30 is made of a milky white resin material (for example, acrylic) containing a light diffusion material (fine particles) such as silica or calcium carbonate, and has a light diffusion function. Note that the cover 30 may be formed of other materials. The cover 30 is attached to the heat sink 90 at the upper end (end on the ceiling side) of the peripheral edge 30b. In the first embodiment, the peripheral edge portion 30 b covers the entire side surface of the light guide plate 20.

  The light source 10 is a so-called SMD (Surface Mount Device) type LED element. Specifically, the SMD type LED element is a package type LED element in which an LED chip (light emitting element) is mounted in a resin-molded cavity, and a phosphor-containing resin is sealed in the cavity. .

  The light source 10 is not limited to such a configuration, and a COB (Chip On Board) type light emitting module in which an LED chip is directly mounted on the substrate 70 may be used as the light source 10. In addition, the light emitting element included in the light source 10 is not limited to the LED. For example, a semiconductor light emitting element such as a semiconductor laser, or another solid light emitting element such as an organic EL (Electro Luminescence) or an EL element such as an inorganic EL. It may be.

  The light source 10 is mounted on the mounting portion 70 b of the substrate 70 so that the light emission side faces the side surface of the light guide plate 20, and emits light toward the side surface of the light guide plate 20. That is, the light source 10 is disposed between the side surface of the light guide plate 20 and the peripheral portion 30 b of the cover 30. The light source 10 is not in contact with the light guide plate 20, and a gap is provided between the light source 10 and the light guide plate 20.

  The light guide plate 20 has a first main surface 20c facing the main body 30a of the cover 30, and is a substantially circular plate-like optical member that guides light from the light source 10 to the first main surface 20c side. . On the second main surface 20d, which is the main surface opposite to the first main surface 20c of the light guide plate 20, a large number of grooves, dot patterns, prism shapes, and the like are formed. Further, the reflection sheet 40 is superimposed on the second main surface 20d. The reflection sheet 40 is a sheet that reflects light made of, for example, polyethylene terephthalate (PET). In the first embodiment, the light guide plate 20 is a light-transmitting resin such as polycarbonate (PC) or acrylic, but may be formed of any other material.

  Here, the light guide plate 20 is characterized in that a reflective portion is provided on the side surface. Hereinafter, the positional relationship between the light source 10, the light guide plate 20, and the reflecting portion will be described with reference to FIG. FIG. 5 is a diagram for explaining the positional relationship between the light source and the light guide plate 20. FIG. 5 is a perspective view of the light source 10 and the light guide plate 20 (reflecting portion) as viewed from the first main surface 20c side, and illustration of other members is omitted.

  As illustrated in FIG. 5, the lighting fixture 100 includes a plurality of light sources (light source 10 and light sources 10 a to 10 f) so as to surround the side surface of the light guide plate 20. Each light source emits light toward the side surface of the light guide plate 20. The light from the light source incident from the side is mainly reflected by the grooves provided on the second main surface 20d, the reflection sheet 40, and the like, and guided to the first main surface 20c.

  Here, the side surface of the light guide plate 20 has a tapered shape that is recessed toward the inside (center side) of the light guide plate 20 when viewed from a direction perpendicular to the first main surface 20c (when viewed in plan). A recess 21 is provided. Here, of the side surfaces of the light guide plate 20, the two inner side surfaces (tapered surfaces) of the recesses 21 are the reflective portion 21 a and the reflective portion 21 b, respectively. Of the side surfaces of the light guide plate 20, the bottom surface of the recess is the light incident portion 21 c.

  The reflection part 21 a and the reflection part 21 b are part of the side surface of the light guide plate 20 and mainly reflect light from the light source 10. That is, the reflecting portions 21a and 21b reflect most of the light incident on the reflecting portions 21a and 21b toward the rear of the light source 10 (the direction opposite to the light guide plate 20). More specifically, part of the light emitted from the light source 10 that has entered the reflecting portions 21 a and 21 b is reflected toward the peripheral portion 30 b of the cover 30 located behind the light source 10.

  The reflecting portion 21 a and the reflecting portion 21 b are provided so as to sandwich the light incident portion 21 c in the circumferential direction of the light guide plate 20. The angles of the reflecting portion 21a and the reflecting portion 21b with respect to the light incident portion 21c are appropriately set in consideration of the position of the light source 10 so that the light from the light source 10 can be efficiently reflected. That is, the angle (taper angle) of the reflecting portion 21a and the reflecting portion 21b with respect to the light incident portion 21c is such that the amount of light reflected from the light source 10 incident on the reflecting portion 21a and the reflecting portion 21b is sufficiently larger than the amount of transmission. Is set.

  The reflective portion 21a and the reflective portion 21b may be subjected to a surface treatment that increases the light reflectance, such as highly reflective coating or aluminum vapor deposition. Thereby, the reflectance of the light of the reflection part 21a and the reflection part 21b becomes larger than the reflectance of the light of the light-guide plate 20, and can reflect the light from the light source 10 efficiently.

  On the other hand, the light incident part 21c mainly transmits the light from the light source 10 and guides it to the first main surface 20c side. Specifically, as described above, the light source 10 emits light toward the light incident portion 21c, and the light from the light source 10 incident on the light incident portion 21c is mainly reflected by the second main surface 20d. And emitted from the first main surface 20c.

  In the first embodiment, the light incident portion 21c is orthogonal to the optical axis of the light source 10, but the reflection portion 21a and the reflection portion 21b (respective reflection surfaces of the reflection portion 22a and the reflection portion 22b) It is not orthogonal to the straight line parallel to the optical axis of (there is no orthogonal portion). That is, the incident surface of the light incident portion 21c and the reflective surfaces of the reflective portion 22a and the reflective portion 22b are not parallel.

  By the way, in the lighting fixture 100, it is the characteristics that the light source 10 and the light sources 10a-10f are arrange | positioned in the position which does not mutually oppose through the light-guide plate 20. FIG. Specifically, the light source is not provided at the position 15 facing the light source 10 via the light guide plate 20.

  As shown in FIG. 5, part of the light from the light source 10 that has entered the light incident portion 21 c passes through the light guide plate 20 and is emitted to the position 15. The light emitted to the position 15 is emitted to the outside from the peripheral portion 30 b of the cover 30 located around the position 15.

  As described above, the plurality of light sources are arranged at positions that do not face each other via the light guide plate 20, so that the peripheral portion 30 b of the cover 30 can be efficiently illuminated by the light that has passed through the light guide plate 20.

  As described above, the luminaire 100 can emit light to the back of the light source 10 that emits light forward, that is, to the side of the light guide plate, by being provided with the reflection portion, by being provided with the reflection portion. it can. That is, the luminaire 100 can emit light from the peripheral edge portion 30 b of the cover 30 to the outside. That is, the luminaire 100 is useful as an edge light type luminaire having a configuration in which light is also distributed to a ceiling surface and a wall surface.

  In addition, the aspect of a reflection part is not limited to such an aspect. FIG. 6 is a diagram illustrating another aspect of the reflecting portion.

  The reflecting portions 21a and 21b described above are planes as shown in FIG. 6A, but, like the light guide plate 20a shown in FIG. 6B, a staircase is formed on the side surface of the light guide plate 20a. A reflection part 22a and a reflection part 22b may be provided. That is, the reflecting part 22a and the reflecting part 22b (respective reflecting surfaces of the reflecting part 22a and the reflecting part 22b) may be stepped.

  Although not shown, a convex portion may be provided on the side surface of the light guide plate instead of the concave portion. Specifically, a convex portion protruding toward the outside of the light guide plate 20 is provided on the side surface of the light guide plate 20, and the reflection portion is a surface corresponding to the side surface of the convex portion among the side surfaces of the light guide plate 20b. Also good.

  Moreover, the reflection part does not need to be integral with the light guide plate. FIG. 7 is a diagram illustrating a reflection portion provided as a separate body from the light guide plate.

  The light guide plate 20b shown in FIG. 7 has a circular plate shape, and a reflection member 23a and a reflection member 23b, which are members different from the light guide plate 20b, are attached to the side surface of the light guide plate 20b. The reflecting members 23a and 23b are substantially triangular prism-shaped members, and one side surface of each of the reflecting member 23a and the reflecting member 23b is attached to the light guide plate 20b. The reflecting member 23a and the reflecting member 23b are attached by, for example, an adhesive, but may be attached by any method such as being fixed by a fixing member such as a screw.

  The side surface of the reflecting member 23a facing the light source 10 is the reflecting portion 24a, and the surface of the reflecting member 23b facing the light source 10 is the reflecting portion 24b. The reflection unit 24 a and the reflection unit 24 b reflect part of the light emitted from the light source 10 toward the rear of the light source 10. In other words, the reflecting member 23a and the reflecting member 23b are convex portions protruding toward the outside of the light guide plate 20b, and the reflecting portion 24a and the reflecting portion 24b are side surfaces of the protruding portion.

  In addition, the reflection member 23a and the reflection member 23b may be made of acrylic like the light guide plate 20b, or may be formed of a material different from the light guide plate 20b such as metal.

  Moreover, the reflection part may be formed by bending a plate-like member that is superimposed on the light guide plate 20b. FIG. 8 is a view for explaining a reflection portion formed by bending a plate-like member.

  As shown in FIG. 8A, the reflecting portion 45a and the reflecting portion 45b are formed as a part of the plate-like member 45 by the plate-like member 45 being stretched and bent. When the portion of the plate-like member 45 that is overlapped with the light guide plate 20b is a plate-like member main body (first plate-like portion), the reflecting portion 45a and the reflecting portion 45b are extended from the plate-like member main body and the peripheral portion of the cover 30 It is located between 30b and the side surface of the light guide plate 20b, and becomes a portion (second plate-like portion) facing the side surface of the light guide plate 20b.

  As shown in FIG. 8C, the plate-like member 45 (FIG. 8A) is attached to the circular plate-shaped light guide plate 20b (FIG. 8B). The reflection part 45 a and the reflection part 45 b are located between the side surface of the light guide plate 20 b and the peripheral edge part 30 b of the cover 30, and reflect a part of the light emitted by the light source 10 to the rear of the light source 10.

  The plate-like member 45 is formed of a metal steel plate such as aluminum or a resin plate such as PBT, for example. The plate member 45 and the above-described substrate 70 may be the same member. In this case, the substrate 70 further includes a portion (second plate-shaped portion) that extends from the substrate body 70a and is located between the side surface of the light guide plate and the peripheral portion 30b of the cover 30, and the reflective portion is provided in the portion. Provided. That is, the light source 10 is mounted on the substrate 70, and the reflection part 45a and the reflection part 45b are provided. When the plate-like member 45 and the substrate 70 are the same member, the number of parts constituting the lighting fixture can be reduced, and the number of assembling steps and the material cost can be reduced.

  The reflecting portion 45a and the reflecting portion 45b do not need to be formed by bending the plate-like member 45. The reflection part 45 a and the reflection part 45 b may be formed separately from the plate-like member 45 and then bonded or welded to the plate-like member 45. Further, as shown in FIG. 8A, the back surface 45c of the reflecting portion 45a (the surface not facing the light source 10) may also have reflectivity.

(Embodiment 2)
A reflection part may be provided in the edge part in the thickness direction of a light-guide plate, respectively. Embodiment 2 demonstrates a lighting fixture provided with the reflection part of such an aspect.

  FIG. 9 is a schematic cross-sectional view of a lighting fixture according to Embodiment 2. In FIG. 9, only the light source 10, the cover 30, and the light guide plate 120 are illustrated, and the other components are the same as those of the lighting fixture 100 and are not illustrated. In the following second embodiment, components that are substantially the same as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The light guide plate 120 provided in the lighting fixture 200 shown in FIG. 9 is provided with a recess on the side surface. Here, unlike the recess provided in the light guide plate 20 of the first embodiment, this recess is the inner side (center) of the light guide plate 120 on a cross-sectional view of the light guide plate 120 cut along a plane perpendicular to the main surface. It is dented towards.

  Of the side surfaces of the light guide plate 120, the curved surface on the ceiling side (hereinafter also referred to as “upper side”) corresponding to the side surface of the concave portion is the reflecting portion 121 a, and among the side surfaces of the light guide plate 120, the floor surface side ( The curved surface (hereinafter also referred to as “lower”) is the reflecting portion 121b. In addition, the reflection part 121a and the reflection part 121b may be provided continuously over the entire periphery of the light guide plate 120, or may be provided intermittently corresponding to the light source 10.

  As shown in FIG. 9B, the reflection part 121 a and the reflection part 121 b reflect part of the light emitted from the light source 10 toward the rear of the light source 10, that is, toward the peripheral part 30 b of the cover 30. .

  Here, in Embodiment 2, the reflecting part 121a and the reflecting part 121b are curved surfaces with different degrees of curvature. FIG. 10 is an enlarged view of the reflecting portion 121a and the reflecting portion 121b.

  As shown in FIG. 10, the side surface of the light guide plate 120 includes the above-described reflecting portion 121 a and the reflecting portion 121 b and a light incident portion 121 c that is a plane corresponding to the bottom surface of the recess. The reflection part 121a and the reflection part 121b are provided so as to sandwich the light incident part 121c in the thickness direction of the light guide plate 120. As in the first embodiment, the light from the light source 10 incident on the light incident part 121c is mainly reflected by the second main surface 120e of the light guide plate 120 and is reflected by the first main surface of the light guide plate 120. The light is emitted from 120d.

  As shown in FIG. 10, the reflecting portion 121a is steeper than the reflecting portion 121b. The reflection part 121a does not reflect much light upward (toward the ceiling). This is because the reflection part 121a is positioned relatively upward in the side surface of the light guide plate 120, and it is not necessary for the reflection part 121a to reflect light further upward than the reflection part 121a.

  On the other hand, the reflection part 121b is positioned relatively upward in the side surface of the light guide plate 120, and even if the reflection part 121b reflects light further upward than the reflection part 121b, the peripheral part of the cover 30 Since it goes to 30b, the reflected light is not wasted.

  As described above, the reflection portions 121a and 121b have different degrees of curvature so as to efficiently reflect light toward the rear of the light source 10.

  As described above, the lighting fixture 200 according to Embodiment 2 can emit light from the peripheral edge portion 30b of the cover 30 to the outside by the reflecting portion 121a and the reflecting portion 121b.

  Also in the second embodiment, the aspect of the reflecting portion is not limited to such an aspect. FIG. 11 is a diagram illustrating another aspect of the reflecting portion.

  Unlike the reflecting portion 121a and the reflecting portion 121b, the reflecting portion 122a and the reflecting portion 122b provided on the light guide plate 120a shown in FIG. 11A have the same degree of curvature. Even with such a reflection part 122a and reflection part 122b, it is possible to reflect the light from the light source 10 toward the rear of the light source 10. Further, like the reflecting portion 123a and the reflecting portion 123b provided on the light guide plate 120b shown in FIG. 11B, the reflecting portion may be a plane.

  As shown in FIG. 11C, a reflecting member 145a and a reflecting member 145b, which are members different from the light guide plate 120c, are provided, and the reflecting portion 124a and the reflecting portion 124b are respectively the reflecting member 145a and the reflecting member. 145b may be provided. In this case, the reflecting member 145a and the reflecting member 145b may be realized as part of a plate-like member (substrate) as in the first embodiment.

(Other embodiments)
As mentioned above, although the lighting fixture which concerns on Embodiment 1 and 2 was demonstrated, this invention is not limited to such an embodiment.

  In the above embodiment, the light guide plate has been described as having a circular plate shape or a substantially circular plate shape, but the shape of the light guide plate is not limited to such a shape. For example, the light guide plate may have a polygonal shape (substantially polygonal) in plan view. FIG. 12 is a diagram illustrating an example in which a reflection portion is provided on a light guide plate having a polygonal shape in plan view.

  Like the light guide plate 220a shown in FIG. 12 (a), the reflection portion 221a and the reflection portion 221b are formed on the side surfaces of the recesses that are recessed inward among the side surfaces of the light guide plate 220a having a polygonal shape in plan view. It may be a corresponding plane. Further, as in the light guide plate 220b shown in FIG. 12B, the recesses (the reflection part 222a and the reflection part 222b) are corners of the light guide plate 220b (locations where the recesses are not provided). May be provided.

  Moreover, like the light guide plate 220c shown in FIG. 12C, the reflection portion 223a and the reflection portion 223b may be provided at the end portions in the thickness direction of the side surfaces of the light guide plate 220c.

  Similarly to the above-described embodiment, the reflecting portion does not have to be a flat surface, and on the side surface of the light guide plate 220d having a polygonal shape in plan view, like the light guide plate 220d shown in FIG. The step-like reflecting portion 224a and the reflecting portion 224b may be provided.

  Even in a light guide plate having a polygonal shape in plan view, the reflecting portion does not need to be integral with the light guide plate. FIG. 13 is a diagram illustrating a reflection portion provided as a separate body from the light guide plate.

  A reflecting member 233a and a reflecting member 233b, which are members different from the light guide plate 220e, are attached to the side surfaces of the light guide plate 220e having a polygonal plan view shown in FIG. The reflecting members 233a and 233b are triangular prism shaped members, and one side of each of the reflecting member 233a and the reflecting member 233b is attached to the light guide plate 220e.

  The side surface of the reflecting member 233a facing the light source 10 is the reflecting portion 225a, and the surface of the reflecting member 233b facing the light source 10 is the reflecting portion 225b. The reflection unit 225 a and the reflection unit 225 b reflect a part of the light emitted forward from the light source 10 toward the rear of the light source 10.

  Further, as shown in FIG. 13B, the reflecting portion 226a and the reflecting portion 226b are formed as a part of the plate-like member 45 by extending the plate-like member 245 to the side surface of the light guide plate 220e. May be.

  As described in the above embodiment, the light sources 10 are arranged with respect to the light guide plate having a polygonal shape in plan view, as shown in FIG. It is better not to face each other. The light source 10 is not necessarily provided on each side. For example, as illustrated in FIG. 14B, the light source 10 is provided along only two sides of the four sides of the rectangular light guide plate 220f. May be.

  Further, in the above embodiment, two reflecting portions are provided for one light source 10, but one reflecting portion may be provided for one light source 10, or two reflecting portions may be provided for one reflecting portion. The light from the light source 10 may be reflected. That is, the position and the number of the reflection parts are not particularly limited.

  In the above embodiment, the lighting fixture is described as a downlight. However, the present invention is realized as another lighting fixture, a lighting device, a light source, or the like using the same idea as the above embodiment. May be.

  In addition, this invention is not limited to these embodiment or its modification. Unless it deviates from the gist of the present invention, various modifications conceived by those skilled in the art are applied to the present embodiment or the modification thereof, or a form constructed by combining different embodiments or components in the modification. It is included within the scope of the present invention.

10, 10a to 10f Light source 15 Position 20, 20a, 20b, 25, 120, 120a to 120c, 220a to 220f Light guide plate 21 Recess 21a, 21b, 22a, 22b, 24a, 24b, 45a, 45b, 121a, 121b, 122a 122b, 123a, 123b, 124a, 124b, 221a, 221b, 222a, 222b, 223a, 223b, 224a, 224b, 225a, 225b, 226a, 226b Reflector 21c, 121c Light incident part 23a, 23b, 145a, 145b, 233a, 233b Reflective member 20c, 25a, 120d First main surface 20d, 25b, 120e Second main surface 30, 35 Cover 30a Main body portion 30b Peripheral portion 40 Reflective sheet 45, 245 Plate member 45c Back surface 50a, 50b, 100 200 luminaire 55 housing 60 ceiling material 70a substrate body 70b mounted portion 75 for mounting the spring 80 power supply unit 90 heat sink

Claims (11)

A light source that emits light forward,
A light guide plate having a first main surface and guiding a part of light emitted from the light source to the first main surface side;
A cover having a light-transmitting property, comprising a main body portion facing the first main surface and a peripheral portion surrounding at least a part of a side surface of the light guide plate;
A reflection portion provided as a part of the light guide plate, or provided between a side surface of the light guide plate and the peripheral portion of the cover;
The light source is disposed between the peripheral portion of the cover and the side surface of the light guide plate so as to emit light toward the side surface of the light guide plate.
The said reflection part is a lighting fixture which reflects another part of the light which the said light source emits toward the back of the said light source. The light source is plural,
The lighting fixture according to claim 1, wherein the plurality of light sources are arranged at positions that do not face each other with the light guide plate interposed therebetween. The side surface of the light guide plate is provided with a recess recessed toward the inside of the light guide plate, and the light source emits light toward the bottom surface of the recess,
The lighting apparatus according to claim 1, wherein the reflecting portion is an inner surface of the recess. The lighting fixture according to claim 3, wherein the reflecting portion is provided at an end portion in a thickness direction of the side surface of the light guide plate. On the side surface of the light guide plate, a convex portion protruding toward the outside of the light guide plate is provided,
The lighting apparatus according to claim 1, wherein the reflecting portion is a side surface of the convex portion. The lighting fixture according to claim 1, wherein the reflecting surface of the reflecting portion has a step shape. The lighting fixture according to any one of claims 1 to 5, wherein the reflecting surface of the reflecting section is not orthogonal to a straight line parallel to the optical axis of the light source. Furthermore, a first plate-like portion that is directly overlaid on a second main surface that is the main surface opposite to the first main surface of the light guide plate, or that is overlapped via another member, and the light guide plate A substrate having a second plate-like portion located between the side surface of the cover and the peripheral edge portion of the cover,
The lighting fixture according to claim 1, wherein the reflecting portion is a surface of the second plate-like portion that faces the light source. The substrate further includes a third plate-like portion positioned between a side surface of the light guide plate and the peripheral portion of the cover,
The lighting apparatus according to claim 8, wherein the light source is provided on a surface of the third plate-shaped portion that faces the side surface of the light guide plate. A part of the light emitted from the light source is incident on a light incident portion of the side surface of the light guide plate,
The light incident part transmits a part of light emitted from the light source mainly inside the light guide plate,
The lighting apparatus according to any one of claims 1 to 9, wherein the reflection unit reflects another part of the light emitted from the light source mainly toward the rear of the light source. The lighting device according to claim 1, wherein the reflecting portion reflects another part of the light emitted from the light source toward the peripheral edge portion of the cover located behind the light source. .

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