JP6241599B2 - Lighting device - Google Patents

Description

  The present invention relates to an illumination device that performs light distribution control using an optical member.

  Lighting devices with various light distribution variations such as LED spotlights and LED universal downlights have been proposed. When these lighting devices are used, for example, in a store, a food supermarket, a living space, etc., it is possible to produce a light effect (space effect) suited to the application.

  In LED spotlights, LED universal downlights, and the like, an optical lens is often installed and used on the irradiation direction side of a light source in order to control light distribution variations. There are various types of optical lenses, and by installing an optical lens selected according to a desired application, it is possible to control light distribution from a wide range of diffusion and narrow angle to wide angle. Thereby, for example, it is possible to produce various light effects according to the usage such as irradiating the irradiated object in a spot manner. Moreover, in the illumination device as described above, a high-power, multi-grain type LED is often employed as a light source, and an optical lens is generally employed in accordance with the multi-grain cup-shaped lens. .

  However, in recent years, the use of integrated LED modules as a light source has been increasing. Since the integrated LED module has a large light emitting unit size, when a conventional cup-shaped lens is adopted as the optical lens, the size of the optical lens becomes large.

  Therefore, in order to make the optical lens thin and small, it has been proposed to employ a Fresnel lens as the optical lens (for example, Patent Document 1).

JP 2007-148017 A

  However, when a Fresnel lens is used as the optical lens, there is a certain distance between the light source and the Fresnel lens. For this reason, depending on the angle of light incident on the Fresnel lens from the light source, the Fresnel lens does not totally reflect and passes through the Fresnel lens as it is. That is, when a Fresnel lens is employed as the optical lens, there is a problem that light (light loss) that cannot be distributed is generated and the central luminous intensity and light flux are reduced.

  Then, this invention is made | formed in view of the above-mentioned situation, and it aims at providing an illuminating device provided with the optical member which can reduce the light (light loss) which cannot perform light distribution control.

  In order to solve the above-described problem, one embodiment of a lighting device according to the present invention includes a light source and an optical member that emits light incident from the light source, and the optical member directly receives light from the light source. And a reflecting portion that emits the light by reflecting the light incident on the incident surface, and the reflecting surface forms a top portion of the protruding portion. And an angle formed between the first reflecting surface and the incident surface is greater than an angle formed between the second reflecting surface and the incident surface. large.

  Further, in one aspect of the lighting device according to the present invention, the light is reflected at an inflection point that is a position where the first reflection surface and the second reflection surface are connected to each other and an angle formed by the incident surface is changed. The angle formed between the light beam and the optical axis of the optical member may be smaller than the angle formed between the second reflecting surface and the optical axis.

  Further, in one aspect of the lighting device according to the present invention, an angle formed between the second reflecting surface and a planar portion of the optical member connected to the second reflecting surface, which is an outer angle of the protruding portion is , Greater than 90 degrees.

  The lighting device according to the aspect of the invention may further include a third reflecting surface connected to the second reflecting surface, and an angle formed between the third reflecting surface and the incident surface may be the first reflecting surface. It is good also as being smaller than the angle which a surface and the said incident surface make, and smaller than the angle which the said 2nd reflective surface and the said incident surface make.

  Further, in one aspect of the lighting device according to the present invention, there are a plurality of the protrusions, and the position where the first reflecting surface and the second reflecting surface are connected to each other and the angle formed by the incident surface is changed. The inflection point may be provided at a position farther from the top of the projection as it gets farther from the center of the optical member in the arrangement direction of the plurality of projections.

  In the aspect of the lighting device according to the present invention, the first reflecting surface may be a substantially flat surface in a cross section including the optical axis of the optical member.

  Moreover, the one aspect | mode of the illuminating device which concerns on this invention WHEREIN: The said optical member is good also as a Fresnel lens.

  ADVANTAGE OF THE INVENTION According to this invention, an illuminating device provided with the optical member which can reduce the light (light loss) which cannot perform light distribution control is realizable.

It is a disassembled perspective view of the illuminating device which concerns on embodiment of this invention. It is sectional drawing of the illuminating device which concerns on embodiment of this invention. It is sectional drawing of an example of the optical member which concerns on embodiment of this invention. It is a partial sectional view of an optical member concerning an embodiment of the invention. It is principal part sectional drawing of the projection part which concerns on embodiment of this invention. It is principal part sectional drawing of the projection part which concerns on embodiment of this invention. It is a partial cross section figure of the optical member which concerns on a comparative example. It is sectional drawing of the optical member of embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each of the embodiments described below shows a preferred specific example of the present invention. Accordingly, the numerical values, shapes, materials, components, arrangement positions and connection forms of components, processes (steps), process orders, and the like shown in the following embodiments are merely examples, and are not intended to limit the present invention. Absent. Therefore, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims showing the highest concept of the present invention are described as optional constituent elements.

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

(Embodiment)
First, lighting device 1 according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an exploded perspective view of a lighting device according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the illumination device of FIG. FIG. 3 is a cross-sectional view of an example of the optical member according to the embodiment of the present invention.

  The illuminating device 1 shown in FIG. 1 and FIG. 2 is used for lighting fixtures, such as a spotlight and a downlight which illuminates light below.

  The lighting device 1 includes an optical member 10, a light source 20, a reflecting plate 30, an instrument main body 40, and a frame body 50. As illustrated in FIG. 1, the lighting device 1 is configured by stacking an instrument body 40, a light source 20, a reflector 30, an optical member 10, and a frame body 50 in this order.

  Hereinafter, each component in the illuminating device 1 is demonstrated in detail.

[Light source 20]
First, the light source 20 will be described.

  The light source 20 is a light emitting module having a light emitting element, for example, and is an LED light source that emits predetermined light radially. The light source 20 is configured to emit white light, for example. The light source 20 includes a base 20b, a plurality of LEDs 20a that are bare chips mounted on the base 20b, and a sealing member that seals the LEDs 20a. 2, the optical axis of the light source 20 is in the vertical direction (downward in the figure).

  The base 20b is a mounting substrate for mounting the plurality of LEDs 20a, and is, for example, a resin substrate, a ceramic substrate, an insulating-coated metal base substrate, or the like. In addition, the base 20b is, for example, a plate having a plane that is rectangular in plan view, and the bottom surface (the upper side in FIG. 2) of the base 20b is attached to the instrument body 40 and fixed. Although not shown, the base 20b is formed with a pair of electrode terminals (a positive electrode terminal and a negative electrode terminal) for receiving DC power from outside for causing the LED 20a (light source 20) to emit light.

[Reflector 30]
Next, the reflector 30 will be described. The reflecting plate 30 has a reflecting function and has an incident port that is an opening through which light from the light source 20 enters and an emitting port that is an opening through which light incident from the incident port exits from the reflecting plate 30. The reflecting plate 30 has an annular frame shape (funnel shape) configured such that the inner diameter gradually increases from the entrance to the exit, and is made of a hard white resin material such as polybutylene terephthalate (PBT). Can be formed.

  The inner peripheral surface of the reflecting plate 30 is a reflecting surface that reflects light from the light source 20, and is configured to reflect the light incident from the incident port and emit the light from the output port.

  The reflector 30 may be formed of a metal material such as aluminum. The reflection plate 30 may be made of resin, and a metal vapor deposition film (metal reflection film) made of a metal material such as silver or aluminum may be formed on the inner surface of the reflection plate 30 as a reflection surface.

[Equipment body 40]
Next, the instrument body 40 will be described. The instrument body 40 supports the light source 20 inside.

  In the present embodiment, the instrument body 40 is a mounting base to which the light source 20 is attached and a heat sink that dissipates heat generated by the light source 20. The instrument main body 40 is formed in a substantially cylindrical shape using a metal material, and is formed, for example, through an aluminum die casting process.

  Specifically, the instrument main body 40 has an attachment portion for attaching the light source 20. That is, the instrument main body 40 fixes the light source 20 by attaching the light source 20 to an attachment part. In addition, the instrument main body 40 is not limited to the case where the light source 20 is directly fixed, but may be fixed to the attachment portion of the instrument main body 40 via a heat dissipation member (heat sink).

  As shown in FIG. 1, a plurality of radiating fins projecting downward are provided in the lower part (lower part in FIG. 1) of the instrument body 40. Thereby, the heat generated by the light source 20 can be efficiently radiated.

[Frame 50]
Next, the frame 50 will be described. The frame 50 is, for example, a lamp, and is fixed to the optical member 10 and the reflection plate 30 by the instrument main body 40 and the frame 50 by being attached to the instrument main body 40.

  A flange projecting outward in the radial direction is integrally formed on the upper end portion (upper end portion in FIG. 2) of the frame body 50 in the circumferential direction. In addition, an entrance for receiving light from the light source 20 that has passed through the optical member 10 is provided on the upper portion of the frame 50. In addition, at the lower part of the frame body 50, there is provided an emission port for emitting light incident on the frame body 50 to the outside. These entrance and exit are opened in a circular shape.

  The frame 50 is formed in a substantially cylindrical shape using a metal material, like the instrument body 40, and is formed, for example, through an aluminum die casting process.

[Optical member 10]
Next, the optical member 10 will be described. The optical member 10 is disposed at a position facing the light source 20 of the instrument body 40 and emits light incident from the light source 20.

  The optical member 10 in the present embodiment is fixed to the inner bottom surface of the frame 50, and the light of the light source 20 incident from one surface (upper surface in FIG. 2) in the thickness direction of the optical member 10 is the one surface. The light is emitted from the other surface (the lower surface in FIG. 2) facing the surface.

  The optical member 10 is formed using a translucent material. For example, the optical member 10 can be formed using a transparent resin material such as PMMA (acrylic) or polycarbonate, or a transparent material having insulation properties such as a glass material. .

  Here, the optical member 10 will be described in detail with reference to FIGS. 3 to 6 with reference to FIG. FIG. 3 is a sectional view of an example of the optical member according to the embodiment, and FIG. 4 is a partial sectional view of an example of the optical member according to the embodiment. 5 and 6 are cross-sectional views of the main part of the protrusion according to the embodiment, and are cross-sectional views of the protrusion in the region X of FIG.

  As shown in FIG. 3, the optical member 10 includes a protrusion 11 that is a polygonal lens formed on one surface in the thickness direction, and a flat surface 12. In the optical member 10, light is incident on the protruding portion 11 side, and the light is emitted in a substantially vertical direction from the flat portion 12 side (the emission surface 101).

  Further, as shown in FIG. 4, the optical member 10 includes an incident surface 111 on which light from the light source 20 is directly incident and a reflecting surface 112 that emits light by reflecting the light incident on the incident surface 111. A protrusion having the same.

  In the present embodiment, as an example of the optical member 10, the protrusion 11 is described using a lens having a Fresnel shape (Fresnel lens), but is not limited to this example. A lens that refracts or transmits is formed at the center of one surface in the thickness direction, and a projection 11 that is a polygonal lens that totally reflects in a region other than the center is formed, and is incident from one side in the thickness direction. What is necessary is just to emit the emitted light from the other in the thickness direction.

  As shown in FIGS. 4 and 5, the reflection surface 112 includes a first reflection surface 112 a that forms the top of the protrusion 11, and a second reflection surface 112 b that is connected to the first reflection surface 112 a. An angle θ1 formed by the first reflecting surface 112a and the incident surface 111 is larger than an angle θ2 formed by the second reflecting surface 112b and the incident surface 111. That is, the relationship θ1> θ2 is satisfied.

  Thus, the 2nd reflective surface 112b is formed inside (incident surface 111 side) rather than the surface (L1 in FIG. 5) of the 1st reflective surface 112a. Here, for example, when the reflecting surface 112 is formed only by the first reflecting surface 112a, light passing through the vicinity of the horizontal surface 113 cannot be reflected. On the other hand, by forming the reflecting surface 112 with the first reflecting surface 112a and the second reflecting surface 112b, the light passing near the horizontal surface 113 can be reflected by the second reflecting surface 112b. In other words, when the reflecting surface 112 is formed only by the first reflecting surface 112a, the light that has passed through without hitting the reflecting surface 112 can be reflected (light control) by providing the second reflecting surface 112b. it can. Thereby, it is possible to reduce light (light loss) that is incident on the optical member 10 but is not emitted in the substantially vertical direction from the plane portion 12 side, and more light is approximately vertical from the plane portion 12 side of the optical member 10. The light can be emitted in the direction.

  Further, light and an optical member that are reflected at an inflection point (position A in the figure), which is a position where the first reflecting surface 112a and the second reflecting surface 112b are connected to each other and an angle formed with the incident surface 111 is changed. The angle θ3 formed by the ten optical axes b1 is preferably smaller than the angle θ4 formed by the second reflecting surface 112b and the optical axes b1 (satisfying θ3 <θ4).

  As a result, the light (P1) incident on the incident surface 111 is refracted and proceeds to the inflection point (position A in the figure) (P2), and is reflected at the inflection point (position A in the figure) of the second reflecting surface 112b. The light (P3) can travel on the second reflecting surface 112b side from the optical axis b1. That is, by forming the second reflecting surface 112b so as to satisfy θ3 <θ4, it is possible to prevent the light reflected by the first reflecting surface 112a from hitting the second reflecting surface 112b, and thus it is difficult for light loss to occur.

  Further, the angle θ5 formed by the second reflecting surface 112b and the flat surface portion (horizontal surface 113) of the optical member connected to the second reflecting surface 112b and the outer angle of the protrusion 11 is larger than 90 degrees. . By satisfying this condition, the protrusion 11 of the present embodiment can be manufactured.

  Here, the position where the inflection point of the reflecting surface 112 should be provided will be described with reference to FIG.

  Of the reflecting surfaces 112 (the first reflecting surface 112a and the second reflecting surface 112b), the first reflecting surface 112a reflects the main light incident on the protrusions 11 in a desired direction (substantially vertical in the figure). Light control can be performed. Thereby, the beam angle and central luminous intensity of the optical member 10 can be increased.

  Therefore, if an inflection point is extremely provided at the position B on the top side of the protrusion 11, the light reflected by the second reflecting surface 112b becomes dominant, and light control that advances the light in the desired direction can be performed. become unable. Therefore, it is preferable to provide the inflection point at a position away from the top of the protrusion 11, and when it is provided in the vicinity of the center of the reflecting surface 112 and at a level where the 1/2 beam angle and the central luminous intensity do not change, for example, at the position A. good.

  As described above, when the inflection point is provided at point A in FIG. 6, it is preferable to provide the second reflecting surface 112b so as to satisfy θ3 <θ4 shown in FIG. This is because, if this is not satisfied (θ3 ≧ θ4), the light reflected by the first reflecting surface 112a hits the second reflecting surface 112b and an optical loss occurs.

  An inflection point may be provided at position C in FIG. In this case, the light (P4) reflected at the inflection point at the position C needs to travel on the incident surface 111 side with respect to the second reflecting surface 112b (L3 in the drawing). In addition, an angle θ5 formed by the second reflecting surface 112b (L6 in the drawing) and the flat surface portion (horizontal surface 113) of the optical member connected to the second reflecting surface 112b and an outer angle of the protrusion 11 is θ5. As described above, it is necessary to be larger than 90 degrees. That is, the angle θ5 needs to be 90 ° + α (α is a draft and a critical angle).

  By providing an inflection point at such a position, it is possible to reduce light (light loss) that is incident on the optical member 10 but is not emitted in the substantially vertical direction from the flat surface portion 12 side, and more light is optically transmitted. It can radiate | emit in the substantially perpendicular direction from the plane part 12 side of the member 10. FIG.

[effect]
As described above, it is possible to realize an illuminating device including an optical member that can reduce light (light loss) that cannot be subjected to light distribution control.

  Here, the effect of the illumination device of the present embodiment will be specifically described with reference to FIGS. 7 and 8. FIG. 7 is a partial cross-sectional view of an optical member according to a comparative example, and FIG. 8 is a cross-sectional view of the optical member of the present embodiment.

  In the comparative example of FIG. 7, the optical member 90 is shown in the case where the reflection surface 912 of the protrusion 91 is formed of only the first reflection surface, and the vicinity of the horizontal surface 913 of the valley between the protrusions 91 (region Y1 in the figure). It can be seen that the light passing through (P5) cannot be reflected.

  On the other hand, in the optical member of the present embodiment shown in FIG. 8, the reflection surface 112 is formed by the first reflection surface 112a and the second reflection surface 112b, so that the vicinity of the horizontal surface 113 (region Y2 in the drawing) is formed. It can be seen that the passing light can be reflected by the second reflecting surface 112b. Here, L1 indicates a virtual surface obtained by extending the first reflecting surface 112a. That is, when the reflecting surface 112 is formed only by the first reflecting surface 112a, the light (P6) that has passed through the reflecting surface 112 (L1 in the drawing) is reflected by the second reflecting surface 112b. (For example, P7 in the figure).

  As described above, according to the optical member 10 of the present embodiment, it is possible to reduce light (light loss) that is incident on the optical member 10 but is not emitted in the substantially vertical direction from the flat surface portion 12 side, and more Light can be emitted in a substantially vertical direction from the flat surface portion 12 side of the optical member 10.

  Table 1 shows changes in luminous intensity and beam angle due to a lens position shift of the illumination device according to the comparative example and the present disclosure. In Table 1, the positional displacement distance (mm) means that the actual distance is d ± even when the optical member 90 and the light source 20 are installed at a constant distance (for example, d) as shown in FIG. Δd (mm) when Δd (mm) is reached. The lighting device of the comparative example is a case where the above-described optical member 90 is used, and the lighting device in the present disclosure is the lighting device 1 in the embodiment.

  From Table 1, it can be seen that in the illumination device of the present disclosure, the influence of the optical characteristics due to the positional deviation is small. When actually manufacturing a lighting device, the light source and the optical member are not misaligned. Therefore, by using the optical member 10 described in the above embodiment for the lighting device, the quality performance of the lighting device is improved. can do. For example, even when multiple lamps are realized by attaching a plurality of lighting devices in the same space, there is an effect that variation in optical characteristics can be suppressed.

(Other embodiments)
Although the lighting device according to the embodiment has been described above, the present invention is not limited to the above embodiment.

  For example, in the present embodiment, an example in which the reflective surface 112 is formed in a two-stage shape of the first reflective surface 112a and the second reflective surface 112b will be described as an example of the multi-level reflective surface 112. It is not limited to a three-stage shape. In this case, there is further provided a third reflecting surface connected to the second reflecting surface 112b, and the angle formed between the third reflecting surface and the incident surface 111 is greater than the angle θ1 formed between the first reflecting surface 112a and the incident surface 111. As well as smaller than the angle θ2 formed between the second reflecting surface 112b and the incident surface 111. Further, the reflecting surface 112 may have a multistage shape of 4 or more. Also in this case, the multi-level reflecting surface may be formed such that the angle formed with the incident surface 111 is smaller as the reflecting surface is from the top to the bottom.

  Moreover, although the 1st reflective surface 112a and the 2nd reflective surface 112b were demonstrated as a substantially plane in the cross section containing the optical axis of the optical member 10, the curved surface which consists of round shape (a part of parabola etc.) may be sufficient. Similarly, each of the multistage reflecting surfaces 112 may be a substantially flat surface or a curved surface having a round shape (a part of a parabola).

  In addition, the optical member 10 of the embodiment has been described as including the plurality of protrusions 11 and providing the first reflection surface 112a and the second reflection surface 112b on all the protrusions 11, but the present invention is not limited thereto.

  For example, the first reflecting surface 112a and the second reflecting surface 112b may be provided at least on the outermost protrusion 11. This is because the effect of reducing light (light loss) can be achieved.

  Moreover, even when providing the 1st reflective surface 112a and the 2nd reflective surface 112b in the some projection part 11 containing all, the position of those inflection points does not need to be fixed. The position of the inflection point may be farther from the top as it approaches the outermost side in the optical member. That is, the inflection point, which is a position where the first reflecting surface 112 a and the second reflecting surface 112 b are connected and the angle between the incident surface 111 is changed, is the optical member 10 in the arrangement direction of the plurality of protrusions 11. It is good also as providing in the position which distances from the top part of the projection part 11, so that it distances from the center of.

  In the above embodiment, the light source 20 has been described as an LED light source. However, the light source 20 is not limited thereto, and may be a light bulb or an organic light emitting element.

  As described above, according to the present invention, an optical member having a multistage reflective surface is a lens having an incident surface on which light from a light source is directly incident and a reflective surface to which light incident on the incident surface is irradiated. By using this, it is possible to realize an illumination device that can reduce light (light loss) that cannot be distributed.

  As mentioned above, although the illuminating device which concerns on one or several aspects was demonstrated based on embodiment, this invention is not limited to this embodiment. Unless it deviates from the gist of the present invention, various modifications conceived by those skilled in the art have been made in this embodiment, and forms constructed by combining components in different embodiments are also within the scope of one or more aspects. May be included.

  In addition, it is realized by arbitrarily combining the components and functions in each embodiment without departing from the scope of the present invention, and forms obtained by making various modifications conceived by those skilled in the art to each embodiment. Forms are also included in the present invention.

DESCRIPTION OF SYMBOLS 1 Illuminating device 10, 90 Optical member 11, 91 Protrusion part 12 Plane part 20 Light source 20a LED
20b Base 30 Reflector 40 Instrument body 50 Frame 101 Emitting surface 111, 911 Incident surface 112, 912 Reflecting surface 112a First reflecting surface 112b Second reflecting surface 113 Horizontal surface

Claims (6)

A light source;
An optical member that emits light incident from the light source;
The optical member is
A projection having an incident surface on which light from the light source is directly incident and a reflecting surface that emits the light by reflecting the light incident on the incident surface;
The reflective surface includes a first reflective surface that forms the top of the protrusion, and a second reflective surface that is connected to the first reflective surface,
The angle between the first reflecting surface and the incident surface is much larger than an angle between the second reflecting surface and the incident surface,
The reflective surface further includes a third reflective surface connected to the second reflective surface,
An angle formed between the third reflecting surface and the incident surface is smaller than an angle formed between the first reflecting surface and the incident surface, and smaller than an angle formed between the second reflecting surface and the incident surface. ,
Lighting device. The angle formed between the light reflected at the inflection point, which is a position where the first reflecting surface and the second reflecting surface are connected to each other and the angle formed with the incident surface is changed, and the optical axis of the optical member. Is smaller than an angle formed by the second reflecting surface and the optical axis.
The lighting device according to claim 1. The angle formed by the second reflecting surface and the planar portion of the optical member connected to the second reflecting surface and the outer angle of the protrusion is greater than 90 degrees.
The illumination device according to claim 1 or 2. There are a plurality of the protrusions,
The inflection point at which the first reflection surface and the second reflection surface are connected to each other and the angle between the incident surface and the incident surface changes is the center of the optical member in the arrangement direction of the plurality of protrusions. It is provided at a position away from the top of the projection as it gets away from
The illumination device according to claim 1 or 2. In a cross section including the optical axis of the optical member,
The first reflecting surface is a substantially flat surface.
The illuminating device of any one of Claims 1-4 . The optical member is a Fresnel lens.
The lighting device according to any one of claims 1 to 5 .

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