WO2021193486A1

WO2021193486A1 - Lighting device

Info

Publication number: WO2021193486A1
Application number: PCT/JP2021/011577
Authority: WO
Inventors: ▲琢▼充小松
Original assignee: 三菱電機株式会社; 三菱電機照明株式会社
Priority date: 2020-03-26
Filing date: 2021-03-22
Publication date: 2021-09-30
Also published as: JP2023158096A; JPWO2021193486A1; JP7346716B2

Abstract

A lighting device is provided with a blue LED module which emits light including a blue light component, a light guide plate which diffuses and surface-emits light from the blue LED module, a white LED module which emits white light, a diffusion plate which is disposed in an orientation intersecting the light guide plate and diffuses the white light from the white LED module, and a light adjustment unit which replicates the color of the sky by adjusting the blue LED module and replicates sunlight by adjusting the white LED module. The light adjustment unit adjusts the white LED module or the blue LED module such that the ratio of the luminance of light emitted by the light guide plate and the luminance of light emitted from the light diffusion plate is 1:5.8-1:13.

Description

lighting equipment

This disclosure relates to a lighting fixture equipped with an LED (Light Emitting Diode).

Conventionally, lighting fixtures that can reproduce the appearance of the sky have been proposed. For example, in the lighting fixture described in Patent Document 1, the state of the sky is controlled by controlling the emission of blue light, yellow light, orange light, red light, and white light by using a light emitting module having LEDs of a plurality of colors. It is configured to be reproduced.

Japanese Unexamined Patent Publication No. 2019-102166

Here, the light from the sky illuminates the window frame around the window when it is inserted into the building through the window. Therefore, in reality, not only the blue light of the sky can be seen through the window, but also the sunlight of the sun illuminated by the light from the sky can be seen around the window. However, in the lighting fixture described in Patent Document 1, only the appearance of the sky seen through the window can be reproduced by the flat plate-shaped light emitting module and the light diffusing plate.

The present disclosure is to solve the above-mentioned problems, and an object of the present disclosure is to provide a lighting fixture capable of improving the reproducibility of light from the sky.

The lighting fixtures of the present disclosure include a blue LED module that emits light containing a blue light component, a light guide plate that diffuses the light of the blue LED module to emit surface light, a white LED module that emits white light, and a light guide plate. The diffuser plate that diffuses the white light of the white LED module and the blue LED module are dimmed to reproduce the sky color, and the white LED module is dimmed to produce the sunlight. The dimming unit is white so that the ratio of the brightness of the light emitted from the light guide plate to the brightness of the light emitted from the diffuser plate is 1: 5.8 to 1:13. Dimming the LED module for light or the LED module for blue.

According to the lighting fixtures of the present disclosure, light from the sky is obtained by dimming the blue LED module that reproduces the color of the sky and the white LED module that reproduces the sunlight light so as to have the above-mentioned brightness ratio. It is possible to improve the reproducibility of.

It is a perspective view which shows the appearance of the lighting fixture which concerns on Embodiment 1. FIG. It is an exploded perspective view which shows the structure of the luminaire which concerns on Embodiment 1. FIG. It is an exploded perspective view which shows the structure of the light source unit of the luminaire which concerns on Embodiment 1. FIG. It is an exploded perspective view which shows the structure of the light source unit of the luminaire which concerns on Embodiment 1. FIG. It is sectional drawing which shows the structure of the lighting fixture which concerns on Embodiment 1. FIG. It is a figure which shows the schematic structure of the blue LED module which concerns on Embodiment 1. FIG. It is a control block diagram of the lighting fixture which concerns on Embodiment 1. FIG. It is a graph which shows the light amount of the blue LED module which concerns on Embodiment 1. FIG. It is a graph explaining the dimming control of the blue LED module which concerns on Embodiment 1. FIG. It is a table which shows the experimental result which confirmed the optimum value of the luminance ratio and the color temperature of the sky simulation part and the ambient light emitting part. It is a table which shows the experimental result which confirmed the preference of the color temperature of the ambient light emitting part in a plurality of prototypes, and the naturalness of both the sky simulation part and the ambient light emitting part combined. It is a table which shows the optimum chromaticity range of the ambient light emitting part based on the experimental result of FIG. 10 and FIG. It is a chromaticity diagram based on the experimental result of FIG. 10 and FIG. It is a table which shows the measurement result of the actual color temperature and brightness of the sky and the sun. It is a table which shows the measurement result of the actual color temperature and brightness of the sky and the sun. It is a table which shows the measurement result of the actual color temperature and brightness of the sky and the sun. It is a table showing the brightness ratio between the actual sky and the sun in the daytime.

Hereinafter, the embodiment of the lighting fixture will be described with reference to the drawings. The luminaire of the present disclosure is not limited to the following embodiments, and can be variously modified. In addition, the luminaire of the present disclosure includes all combinations of configurations that can be combined among the configurations shown in the following embodiments. Further, in each figure, those having the same reference numerals are the same or equivalent thereof, which are common in the entire text of the specification. Further, in the entire text of the specification, the vertical direction from the floor surface to the ceiling is referred to as "upward direction", and the ceiling side is referred to as "upper side". Similarly, the vertical direction from the ceiling to the floor surface is referred to as "downward", and the floor surface side is referred to as "lower side". In each drawing, the relative dimensional relationship or shape of each component may differ from the actual one.

Embodiment 1.
FIG. 1 is a perspective view showing the appearance of the lighting fixture 1 according to the first embodiment. The lighting fixture 1 is a ceiling-embedded lighting fixture, and includes a fixture main body 50 embedded in the ceiling and a light source unit 10 attached to the fixture main body 50. The light source unit 10 includes a diffuser plate 13 that emits white light and a light guide plate 17 that emits blue light. The lighting fixture 1 can provide lighting having a deep visual effect as if looking at the sky through a window frame by using blue light from the light guide plate 17 and white light from the diffuser plate 13.

FIG. 2 is an exploded perspective view showing the configuration of the lighting fixture 1 according to the first embodiment. The luminaire 1 is embedded and installed in an embedded hole H provided in the ceiling C. As shown in FIG. 2, the fixture body 50 of the lighting fixture 1 is formed in a rectangular box shape and has an opening on the lower side. The instrument body 50 has a main surface 51 and four side surfaces 52. Each of the side surfaces 52 is provided so as to extend vertically downward from each of the four sides of the main surface 51.

Of the four side surfaces 52 of the instrument body 50, the V spring mounting bracket 53 is attached to the inner surface of the two opposite side surfaces 52. The V-spring mounting bracket 53 hooks and holds the V-spring 12 provided on the light source unit 10, which will be described later. Further, bolt holes 51-1 are provided at the four corners of the main surface 51. Further, a hanging bolt B is hung from the embedded hole H of the ceiling C. The instrument body 50 is fixed to the ceiling C by inserting the hanging bolt B into the bolt hole 51-1 and then tightening the hanging bolt B with the nut 61.

Further, the main surface 51 is provided with an electric wire hole 51-2 and a terminal block 54. The terminal block 54 has a power supply terminal block and a signal line terminal block. In FIG. 2, the power supply terminal block and the signal line terminal block are not shown. An electric wire and a signal line are drawn out from the electric wire hole 51-2. The electric wire drawn from the electric wire hole 51-2 is electrically connected to the power terminal block of the terminal block 54. Further, the signal line drawn from the electric wire hole 51-2 is electrically connected to the signal line terminal block of the terminal block 54.

The light source unit 10 is arranged inside the opening of the fixture body 50. The light source unit 10 includes an upper cover 27, a flange portion 11, a V spring 12, a diffusion plate 13, and a light guide plate 17. The upper cover 27 is formed on a quadrangular pyramid with an open lower end. Each of the four side surfaces of the upper cover 27 is formed in a trapezoidal shape, and the length of the upper side is shorter than the length of the lower side. The flange portion 11 is formed in a rectangular frame shape in a plan view. As shown in FIG. 2, the flange portion 11 is arranged so as to project from the lower end of the upper cover 27 toward the outside in the horizontal direction.

The V spring 12 is a wire spring formed by bending a metal wire rod into a V shape, and is attached to the upper surface of the flange portion 11. A total of four V-springs 12 are provided according to the positions of the V-spring mounting brackets 53 of the instrument main body 50. When the V spring 12 engages with the V spring mounting bracket 53, the light source unit 10 is suspended and held by the fixture body 50. When the lighting fixture 1 is attached to the embedded hole H in the ceiling C, the flange portion 11 covers the edge of the embedded hole H. Therefore, when the lighting fixture 1 is attached to the embedded hole H of the ceiling C, the embedded hole H cannot be seen by the user.

3 and 4 are exploded perspective views showing the configuration of the light source unit 10 of the lighting fixture 1 according to the first embodiment. The light source unit 10 includes the components shown in FIG. 3 and the components shown in FIG. FIG. 3 shows the components provided in the lower portion of the light source unit 10, and FIG. 4 shows the components provided in the upper portion of the light source unit 10.

Among the components of the light source unit 10, first, the components shown in FIG. 3 will be described. As shown in FIG. 3, the light source unit 10 includes a flange portion 11, a V spring 12, a packing 21, a diffusion plate 13, a packing 22, a white LED module 14, and a module holding portion 15.

As described above, the flange portion 11 is formed in a rectangular frame shape. The flange portion 11 is made of, for example, metal. A total of four V-springs 12 are provided on the upper surface of the flange portion 11.

The module holding portion 15 is formed in a rectangular frame shape in a plan view. The module holding portion 15 is configured by combining four members. Each of the four members has an L-shaped cross section, as shown in FIG. 5, which will be described later. Further, as shown in FIG. 3, a mounting flange 15-1 is provided at the lower end of each of the four members of the module holding portion 15. The mounting flange 15-1 is attached to the flange portion 11 with screws.

The white LED module 14 has three substrates 140 and two types of

white LEDs

141 and 142 having different color temperatures provided inside each of the three substrates 140. The three substrates 140 of the white LED module 14 are arranged in a U shape in a plan view so as to form three sides of a rectangle. The angle formed by the adjacent substrates 140 is 90 °. The white LED module 14 emits white light from three directions forming a U shape.

The white LED 141 is, for example, a daytime LED having a color temperature of 4000 to 5000 (K), and the white LED 142 is, for example, a light bulb color LED having a color temperature of 2600 to 3000 (K). The white LED module 14 can emit white light having various color temperatures and various amounts of light by changing the dimming rate of the

white LEDs

141 and 142. Further, the white LED 141 and the white LED 142 may be dimmed according to the time of day. For example, the white LED 141 and the white LED 142 are dimmed so that the amount of light is 100% in the daytime, the amount of light is 50% at dawn and evening, and the amount of light is 20% at night. Further, the white LED 141 and the white LED 142 are dimmed so as to have a neutral white color temperature of 4500K in the daytime, a light bulb color having a color temperature of 3000 to 3500K in the evening, and a color temperature of 4000 to 3800K at night. ..

A light emitting element or a light emitting device other than the LED may be used as the light source of the white LED module 14. Further, the white LED module 14 may include only one type of white LED, or may include three or more types of white LEDs. The white LED module 14 is arranged inside the module holding portion 15 and is held by the module holding portion 15.

The packing 22 is formed in a rectangular narrow frame shape in a plan view. The packing 22 is arranged between the upper end surface of the diffusion plate 13 and the lower surface which is the exit surface of the light guide plate 17 shown in FIG. The packing 22 shields the light emitted from the blue LED module 18, which will be described later, from entering the upper end surface of the diffuser plate 13 from the emission surface of the light guide plate 17. Further, the packing 22 shields the white light emitted from the white LED module 14 from entering the exit surface of the light guide plate 17 from the upper end surface of the diffuser plate 13. Further, the packing 22 also functions as a cushioning material when the lighting fixture 1 is shaken by an earthquake or the like.

The diffusion plate 13 is made of, for example, white resin, and is formed in a rectangular frame shape in a plan view. The diffuser plate 13 has a quadrangular pyramid shape with the upper and lower sides open. That is, each of the four side surfaces of the diffuser plate 13 is inclined at a preset angle with respect to the vertical direction. Each of the four side surfaces of the diffuser plate 13 is composed of a trapezoidal plate, and the length of the upper side is shorter than the length of the lower side. Further, since each of the four side surfaces of the diffusion plate 13 is inclined, the position of the upper side is arranged so as to be inside the position of the lower side in a plan view. As a result, the internal space of the diffuser plate 13 is tapered downward. The diffusion plate 13 may be formed by combining four trapezoidal plates, or may be integrally formed.

Of the four side surfaces of the diffuser plate 13, three surfaces are light emitting surfaces 13-1 and the other one surface is a non-light emitting surface 13-2. The three light emitting surfaces 13-1 are arranged in a U shape. Here, on each of the four side surfaces of the diffuser plate 13, the inner surface facing the internal space of the diffuser plate 13 is referred to as a front surface, and the outer surface is referred to as a back surface.

The diffuser plate 13 is arranged inside the white LED module 14. That is, the white LED module 14 is arranged on the back side of each of the light emitting surfaces 13-1 of the diffuser plate 13. The white light emitted from the white LED module 14 enters from the back surface of the light emitting surface 13-1 of the diffuser plate 13, passes through the light emitting surface 13-1, and is emitted from the front surface of the light emitting surface 13-1. Since each of the light emitting surfaces 13-1 is inclined, the white light emitted from the front surfaces of the three light emitting surfaces 13-1 irradiates diagonally downward.

A light-shielding sheet (not shown) is attached to the back surface of the non-light emitting surface 13-2 of the diffusion plate 13 so that light does not leak from the non-light emitting surface 13-2.

As described above, the diffuser plate 13 has a configuration in which three light emitting surfaces 13-1 and one non-light emitting surface 13-2 that does not emit light are combined. As a result, the light emitted from the diffuser plate 13 becomes light from three directions, giving a sense of depth as if the light from the outside is shining through the window frame in the sun illuminated by sunlight or the window frame in the shade. It is possible to produce a certain visual effect.

The diffusion plate 13 is placed on the flange portion 11 via the packing 21. The packing 21 is formed in a rectangular narrow frame shape in a plan view. The packing 21 prevents the flange portion 11 or the diffusion plate 13 from directly colliding with each other when the flange portion 11 or the diffusion plate 13 vibrates. Further, due to the elasticity of the packing 21, the force applied from the flange portion 11 to the diffusion plate 13 is relaxed, and damage to the diffusion plate 13 can be suppressed. Further, by providing the packing 21 between the flange portion 11 and the diffusion plate 13, the impression as a window frame can be given. In particular, when the packing 21 has a white color tone, the impression as a window frame can be strengthened. The packing 21 also functions as a light-shielding portion for preventing white light from leaking from the gap between the diffusion plate 13 and the flange portion 11.

Next, among the components of the light source unit 10, the components shown in FIG. 4 will be described. As shown in FIG. 4, the light source unit 10 is further fixed to the lower guide plate 16, the light guide plate 17, the blue LED module 18, the upper guide plate 19, the insulating portion 23, and the module holding portion 24. A member 25, a light guide plate cover 26, and an upper cover 27 are provided. Further, the light source unit 10 further includes a power supply device 31 arranged on the upper surface of the upper cover 27 and a dimming unit 32.

The lower guide plate 16 is placed on the module holding portion 15 shown in FIG. The lower guide plate 16 is composed of two rod-shaped members, and is arranged below the light guide plate 17 along an end extending in the longitudinal direction of the light guide plate 17. Protrusions 16-3 are provided at both ends of the two rod-shaped members constituting the lower guide plate 16. The protrusions 16-3 extend vertically upward. The protrusions 16-3 come into contact with the end face 17-2 extending in the lateral direction of the light guide plate 17 to restrict the movement of the light guide plate 17 in the longitudinal direction.

The upper guide plate 19 is placed on the light guide plate 17. The upper guide plate 19 is composed of two rod-shaped members and is arranged along an end portion extending in the longitudinal direction of the light guide plate 17.

The light guide plate 17 is formed in a rectangular plate shape in a plan view. The light guide plate 17 diffuses the light emitted from the blue LED module 18 and emits blue light from the lower surface, which is the exit surface. The light guide plate 17 is made of an acrylic resin and contains, for example, silica as a scatterer which is a particle that scatters light. The end portion of the light guide plate 17 in the longitudinal direction is sandwiched between the lower guide plate 16 and the upper guide plate 19 from the vertical direction.

The upper surface of the light guide plate 17 is smooth because it is totally reflected. The upper surface of the light guide plate 17 is preferably mirror-finished. If the upper surface of the light guide plate 17 is scratched during the assembly work of the lighting fixture 1, total reflection is less likely to occur at the scratched portion. Therefore, a part of the lower surface corresponding to the scratched portion on the upper surface appears to shine whitish. Therefore, in order to prevent the upper surface of the light guide plate 17 from being scratched, the upper surface of the light guide plate 17 may be covered with a reflective sheet (not shown).

The blue LED module 18 is arranged so as to be parallel to the end face 17-1 extending in the longitudinal direction of the light guide plate 17. The blue LED module 18 includes two substrates 180 and a plurality of LEDs arranged on the substrate 180, respectively. A plurality of through holes 18-1 are provided in the upper part of the substrate 180. The configuration and dimming control of the blue LED module 18 will be described in detail later.

The blue LED module 18 is attached to the module holding portion 24 by the fixing member 25. A cylindrical protrusion 25-1 is provided on the surface of the fixing member 25 on the blue LED module 18 side. The protrusions 25-1 are inserted into through holes 18-1 of the substrate 180 of the blue LED module 18. The fixing member 25 is screwed to the module holding portion 24 in a state where the protruding portion 25-1 is inserted into the through hole 18-1.

The module holding portion 24 is formed of a sheet metal having an L-shaped cross section. The module holding unit 24 not only holds the substrate 180 of the blue LED module 18, but also functions as a heat sink that releases heat from the blue LED module 18 to the outside. The module holding portion 24 is attached to the upper surface of the module holding portion 15 shown in FIG. Further, the blue LED module 18 is attached to the module holding portion 24 via the insulating portion 23. If the substrate 180 of the blue LED module 18 is not a double-sided substrate, the insulating portion 23 may be omitted.

The light guide plate cover 26 is placed on the upper guide plate 19. The light guide plate cover 26 covers the light guide plate 17 from above and protects the light guide plate 17. The upper cover 27 covers the components of the light source unit 10 shown in FIGS. 3 and 4 and protects the components. The power supply device 31 and the dimming unit 32 are mounted on the upper surface of the upper cover 27.

The power supply device 31 supplies electric power to the blue LED module 18 and the white LED module 14. The dimming unit 32 dims each LED included in the blue LED module 18 and the white LED module 14. The dimming unit 32 of the present embodiment dims the blue LED module 18 to reproduce the color of the sky, and dims the white LED module 14 to reproduce the sunlight. The power supply device 31 and the dimming unit 32 are electrically connected by wiring such as a crossover wiring. Further, the power supply device 31 and the dimming unit 32 are electrically connected to the power supply terminal block and the signal terminal block of the terminal block 54 of the instrument body 50 in a state where the light source unit 10 is attached to the instrument body 50.

FIG. 5 is a schematic cross-sectional view showing the configuration of the lighting fixture 1 according to the first embodiment. FIG. 5 schematically shows a cross section of the luminaire 1 cut in a plane parallel to one side surface in the lateral direction in the central portion in the longitudinal direction.

As shown in FIG. 5, the light source unit 10 is arranged in the opening at the lower end of the instrument body 50. A V spring 12 is provided on the upper surface of the flange portion 11 of the light source unit 10. The V-spring 12 is held in a state of being hooked on the V-spring mounting bracket 53 provided on the instrument main body 50. As a result, the light source unit 10 and the instrument body 50 are engaged with each other, and the light source unit 10 is held by the instrument body 50.

The white LED module 14 is held by the module holding portion 15 and is arranged on the back surface of the diffuser plate 13. Further, the blue LED module 18 is held by the module holding portion 24 fixed to the upper surface of the module holding portion 15, and is arranged so as to face the end surface of the light guide plate 17 via the gap 33. The diffusion plate 13 and the light guide plate 17 are arranged so as to intersect each other. Specifically, the light guide plate 17 is arranged parallel to the ceiling C, and the diffusion plate 13 is arranged so as to extend diagonally downward from the light guide plate 17.

The light emitted from the blue LED module 18 is incident on the end surface 17-1 of the light guide plate 17 and travels in the light guide plate 17 while being totally reflected by the upper surface and the lower surface of the light guide plate 17. A part of the light traveling in the light guide plate 17 hits the scattering body in the light guide plate 17 and is diffused, and surface-emitted from the lower surface of the light guide plate 17. The light guide plate 17 and the blue LED module 18 constitute an sky simulation unit that reproduces the color of the sky seen through a window. Further, the white light emitted from the white LED module 14 is incident on the back surface of the diffuser plate 13 and emitted from the front surface of the light emitting surface 13-1 of the diffuser plate 13. Since the light emitting surface 13-1 is inclined, the white light emitted from the front surface of the light emitting surface 13-1 illuminates diagonally downward. The diffuser plate 13 and the white LED module 14 constitute an ambient light emitting unit that reproduces the sunlight that is inserted around the window.

Next, the configuration and dimming control of the blue LED module 18 in the present embodiment will be described. FIG. 6 is a diagram showing a schematic configuration of the blue LED module 18 according to the first embodiment. FIG. 6 shows a schematic configuration of one substrate 180 in the blue LED module 18, but the configuration of the other substrate 180 is the same as that of FIG. As shown in FIG. 6, a plurality of white LEDs 181 and blue LEDs 182 and green LEDs 183 are arranged on the substrate 180 of the blue LED module 18. Specifically, on the substrate 180, two white LEDs 181 and two blue LEDs 182 and one green LED 183 are arranged as one set, and a plurality of sets are arranged in a row.

The number and arrangement of the white LEDs 181 and the blue LEDs 182 and the green LEDs 183 arranged on the substrate 180 of the blue LED module 18 are not limited to the example of FIG. For example, the white LED 181 and the blue LED 182 and the green LED 183 may be arranged in the lower region of the substrate 180. In this case, the light guide plate 17 and the diffuser plate 13 can be arranged close to each other, and the blue light from the light guide plate 17 and the white light from the diffuser plate 13 can be emitted in close proximity to each other. Further, the white LED 181 and the blue LED 182 and the green LED 183 may be arranged so as to be displaced in the vertical direction. Further, the arrangement of the white LED181, the blue LED182, and the green LED183 may be appropriately determined in consideration of the color variation and the design of the substrate. However, in order to reproduce the color of the sky, it is desirable that the ratio of the numbers of the white LEDs 181 and the blue LEDs 182 and the green LEDs 183 to the total number of LEDs in the blue LED module 18 is 2: 2: 1.

A plurality of through holes 18-1 are provided on the upper part of the substrate 180 of the blue LED module 18. The through hole 18-1 (not shown) provided in the central portion of the substrate 180 is circular, and the other through holes 18-1 are elliptical extending in the longitudinal direction. The substrate 180 of the blue LED module 18 is thermally expanded and contracted by the heat generated from the white LED 181 and the blue LED 182, and the green LED 183. Therefore, when the blue LED module 18 is fixed to the module holding portion 24, the substrate 180 of the blue LED module 18 may be warped or distorted due to thermal expansion and contraction.

Therefore, in the present embodiment, the substrate 180 is provided with an elliptical through hole 18-1, and the protrusion 25-1 of the fixing member 25 can be inserted into the through hole 18-1 with play. As a result, even when the substrate 180 of the blue LED module 18 is thermally expanded and contracted, the protrusion 25-1 can move in the elliptical through hole 18-1 in the longitudinal direction, and the substrate 180 can be moved. Warpage or distortion can be suppressed.

The white LED 181 is, for example, an LED having a color temperature of 5000 (K) and a forward voltage of 6 V. The blue LED 182 is an LED having a dominant wavelength of 470 nm or less and a forward voltage of 3 V. The green LED 183 is, for example, an LED having a dominant wavelength of 510 to 570 nm and a forward voltage of 3 V. The white LED 181 has a higher forward voltage than the blue LED 182 and the green LED 183, and emits light brighter than the blue LED 182 and the green LED 183 when the same current flows. That is, the output balance of each LED in the blue LED module 18 is white LED181> blue LED182> green LED183.

The blue LED module 18 of the present embodiment controls the light emission of the white LED181, the blue LED182, and the green LED183 to reproduce the color of the sky, particularly the color of the blue sky. As described above, by using the three colors of white, blue, and green, the color rendering property can be improved as compared with the case of using the three colors of red, blue, and green.

FIG. 7 is a control block diagram of the lighting fixture 1 according to the first embodiment. As shown in FIG. 7, the power supply device 31 includes a first power supply device 31a, a second power supply device 31b, and a second power supply device 31a for passing a current through the white LED 181 of the blue LED module 18, the blue LED 182, and the green LED 183, respectively. A power supply device 31c is provided. By providing a power supply device for each LED individually, it is possible to control the emission color of the blue LED module 18 in two dimensions, so that various blue skies can be reproduced. The power supply device 31 further includes a fourth power supply device 31d and a fifth power supply device 31e for passing a current through the white LED 141 and the white LED 142 of the white LED module 14, respectively.

Further, the dimming unit 32 has a first control circuit 32a that transmits a first dimming signal to the first power supply device 31a and a second power supply device 31b, and a second dimming signal that transmits a second dimming signal to the third power supply device 31c. The two control circuits 32b and the like are provided. That is, the first control circuit 32a controls the light emission of the white LED 181 and the blue LED 182 of the blue LED module 18, and the second control circuit 32b controls the light emission of the green LED 183 of the blue LED module 18.

Further, the dimming unit 32 further includes a third control circuit 32c that transmits a third dimming signal to the fourth power supply device 31d and a fourth control circuit 32d that transmits a fourth dimming signal to the fifth power supply device 31e. And. That is, the third control circuit 32c controls the light emission of the white LED 141 of the white LED module 14, and the fourth control circuit 32d controls the light emission of the white LED 142 of the white LED module 14. The first to fourth control circuits 32a to 32d have, for example, timers (not shown) and control the first to fifth power supply devices 31a to 32e according to the time. The first to fourth control circuits 32a to 32d are composed of hardware such as a dedicated single circuit or composite circuit, a microcomputer or processor that executes a program stored in a memory, or a combination thereof.

As described above, in the present embodiment, the first control circuit 32a performs the same control on both the white LED 181 and the blue LED 182 of the blue LED module 18. As a result, lighting control can be simplified and the number of control circuits can be reduced as compared with the case where a control circuit is provided for each LED. In the case of this embodiment, the number of control circuits can be four, which facilitates the development of the lighting fixture 1.

The first to fifth dimming signals are, for example, PWM (Pulse Width Modulation) signals, and the amount of light is changed according to the duty ratio of the PWM signals. The power supply device 31 performs dimming control between the blue LED module 18 and the white LED module 14 by changing the current flowing through each LED based on the PWM signal.

FIG. 8 is a graph showing the amount of light of the blue LED module 18 according to the first embodiment. The horizontal axis of FIG. 8 indicates the time, and the vertical axis indicates the amount of light of the blue LED module 18. In the blue LED module 18 of the present embodiment, the amount of light is changed according to the time, similarly to the white LED module 14. Specifically, as shown in FIG. 8, the amount of light in the daytime (for example, from 8:00 to 16:00) is 100%, and the amount of light in the dawn (for example, from 6:00 to 8:00) and in the evening (for example, from 16:00 to 18:00) is 50. %, And the amount of light at night (for example, from 18:00 to 6:00) is 20%. The time shown in FIG. 8 is merely an example, and is not limited to the example shown in FIG. 8, and may be set as appropriate. Further, the amount of light at each time may be changed according to the season. For example, when the season is summer, the daytime time when the amount of light of the blue LED module 18 is 100% may be longer than in the case of winter. Further, not only the amount of light of the blue LED module 18 but also the chromaticity may be changed according to the season.

FIG. 9 is a graph illustrating dimming control of the blue LED module 18 according to the first embodiment. The horizontal axis of FIG. 9 indicates the time, and the vertical axis indicates the duty ratio of the dimming signal. The solid line in FIG. 9 shows the first dimming signal output from the first control circuit 32a, and the broken line shows the second dimming signal output from the second control circuit 32b. As shown in FIG. 9, the first control circuit 32a and the second control circuit 32b set the duty ratio of the first dimming signal and the second dimming signal in the daytime to 1.

Then, in the evening (for example, 16:00), the first control circuit 32a reduces the duty ratio of the first dimming signal to 0.2 at a preset first reduction rate. Further, the second control circuit 32b reduces the duty ratio of the second dimming signal to 0.2 at a second reduction rate larger than the first reduction rate. As a result, the amount of light of the green LED 183 is first reduced to 20%, and then the white LED 181 and the blue LED 182 are reduced to 20%.

Also, at dawn, the opposite control is performed in the evening. Specifically, first, the first control circuit 32a increases the duty ratio of the first dimming signal to 1 at a preset first increase rate. The second control circuit 32b increases the duty ratio of the second dimming signal to be larger than the first increase rate after a predetermined time has elapsed (for example, 6 o'clock) after the first control circuit 32a increases the duty ratio. Increase to 1 at the second rate of increase.

By performing such control, the amount of light of the green LED 183 first decreases in the evening, and then the white LED 181 and the blue LED 182 decrease, so that the light from the light guide plate 17 becomes purplish deep blue like natural light. Can be changed to.

Further, in the present embodiment, the sky simulation is performed so that not only the sky light reproduced by the sky simulation unit but also the entire light including the sunlight reproduced by the ambient light emitting unit reproduces the actual natural light. The part and the ambient light emitting part are dimmed. FIG. 10 is a table showing the experimental results for confirming the optimum values of the brightness ratio and the chromaticity between the sky simulation unit and the ambient light emitting unit.

The brightness ratio shown in FIG. 10 is the ratio of the brightness of the ambient light emitting portion to the brightness of the sky simulated part, and is a value obtained by dividing the brightness of the light emitted from the diffuser plate 13 by the brightness of the light emitted from the light guide plate 17. Further, in FIG. 10, the chromaticity of the sky simulation unit and the ambient light emitting unit is shown by the xy coordinate system (x, y) of the CIE chromaticity diagram. "OK", "Δ" or "NG" in "favorability" and "evaluation" shown in FIG. 10 is judged by whether or not it looks like an actual sky. For example, when the brightness of the ambient light emitting unit becomes high, the light emitted from the sky simulation unit loses to the ambient light emitting unit, so that the light from the ambient light emitting unit looks like illumination. However, when the color temperature of the ambient light emitting portion becomes low, the ambient light emitting portion does not look like illumination, but when the color temperature of the ambient light emitting portion becomes too low, the impression of evening is obtained. “Δ” indicates a result that is an acceptable value but cannot be said to be OK.

From the experimental results of FIG. 10, the brightness ratio between the sky simulated part and the ambient light emitting part, that is, the brightness of the light emitted from the light guide plate 17: the brightness of the light emitted from the diffuser plate 13 is preferably 1: 5.8 to 1: 7. , 1: 7 was found to be the optimum value. The optimum chromaticity of light emitted from the diffuser plate 13 is (0.338, 0.345) to (0.363, 0.355) in the xy coordinate system (x, y) of the CIE chromaticity diagram. It turned out that there was.

FIG. 11 is a table showing the experimental results confirming the preference of the color temperature of the ambient light emitting part in a plurality of prototypes and the naturalness of both the sky simulation part and the ambient light emitting part combined. As shown in FIG. 11, when the prototype 103 and the prototype 104 are compared, the brightness ratios are the same, but due to the difference in the absolute values of the brightness of the sky simulated part and the ambient light emitting part, both the sky simulated part and the ambient light emitting part are both. It was found that the overall naturalness including the above was different. That is, it was found that the luminance ratio and the chromaticity had a range of optimum values.

FIG. 12 is a table showing the optimum chromaticity range of the ambient light emitting portion based on the experimental results of FIGS. 10 and 11. As shown in FIG. 12, the optimum chromaticity range of light emission from the ambient light emitting portion, that is, the diffuser plate 13 is (0.3376, 0.3616) in the xy coordinate system (x, y) of the CIE chromaticity diagram. , (0.3366, 0.3369), (0.3630, 0.3550), (0.3660, 0.3820).

FIG. 13 is a chromaticity diagram based on the experimental results of FIGS. 10 and 11. The dotted line shown in FIG. 13 is a blackbody locus, and the broken line is CIE daylight. Further, FIG. 13 shows a color temperature range of 4000K, 4500K, 5000K, 5700K, and 6500K defined by ANSI (American National Standards Institute). Further, in FIG. 13, the ambient light emitting portion in the case of the brightness ratios of 1: 4, 1: 5, 1: 5.8, 1: 6.2, 1: 6.5, 1: 7 in the experimental result of FIG. The chromaticity of the above and the chromaticity of the ambient light emitting portion of the prototypes 101, 102, 103, 104 in the experimental result of FIG. 11 are shown.

The range shown by the thick line in FIG. 13 is the range including the chromaticity of the ambient light emitting portion judged to be “OK” or “Δ” in the experimental results of FIGS. 10 and 11. This range includes the chromaticity when the luminance ratio is 1: 5.8 to 1: 7 and the chromaticity of the prototypes 101, 103, and 104. This range is the chromaticity coordinates (0.3376, 0.3616), (0.3366, 0.3369), (0.3630, 0.3550), (0.3660,) of the ambient light emitting portion shown in FIG. It is a range surrounded by a square connecting the four points of 0.3820), and is a recommended color temperature range of the ambient light emitting part.

FIGS. 14, 15 and 16 are tables showing actual measurement results of chromaticity and brightness of the sky and the sun. Specifically, FIG. 14 shows the measurement result of the sky of Ofuna, Kamakura City, Kanagawa Prefecture on April 3, 2019, and FIG. 15 shows the measurement result of the sky of Ofuna, Kamakura City, Kanagawa Prefecture on April 15, 2019. , Fig. 16 is the measurement result of the sky of Ofuna, Kamakura City, Kanagawa Prefecture on April 16, 2019. The weather will be fine in both cases. Further, the "time" shown in FIGS. 14 to 16 is the measurement start time, and there is a variation of about 15 minutes from the actually measured time. For example, when it is described as "10:55", it is the result measured between "10:55 and 11:10". The measurement field of view is 0.1 °. Further, the measured values shown as "north", "east", "south", and "west" are measured values at an angle of about 20 deg with respect to the horizontal plane. Further, the measured values indicated as "heaven (north)", "heaven (east)", and "heaven (west)" are measured values at an angle of about 70 deg from the horizontal plane. In addition, "Hyuga" was measured by shining natural light on white copy paper.

FIG. 17 is a table showing the brightness ratio between the actual sky and the sun in the daytime. FIG. 17 shows the maximum value, the average value, and the minimum value of the brightness ratio (brightness of the sun / brightness of the sky) between 10:00 and 14:00, which is generally assumed to be daytime, which is shown in a thick frame in FIGS. 14 and 15. including. It can be seen that the brightness ratios of 1: 5.8 to 1: 7 derived from the experimental results shown in FIG. 10 are equivalent to the actual brightness ratios of the sky and the sun shown in FIG. Further, according to the result shown in FIG. 17, the actual brightness ratio between the sky and the sun in the daytime is 12.964 at the maximum. Therefore, the ratio of the brightness of the light emitted from the light guide plate 17 to the brightness of the light emitted from the diffuser plate 13 may be 1: 5.8 to 1:13.

Based on the above, the dimming unit 32 of the present embodiment is white so that the ratio of the brightness of the light emitted from the light guide plate 17 to the brightness of the light emitted from the diffuser plate 13 is 1: 5.8 to 1:13. LED module 14 and / or blue LED module 18 are dimmed. Preferably, the dimming unit 32 is a white LED module 14 or a white LED module 14 so that the ratio of the brightness of the light emitted from the light guide plate 17 to the brightness of the light emitted from the diffuser plate 13 is 1: 5.8 to 1: 7. Dimming the blue LED module 18 or both.

Further, in the dimming unit 32, the chromaticity of the light emitted from the diffuser plate 13 is (0.3376, 0.3616), (0.3366,0) in the xy coordinate system (x, y) of the CIE chromaticity diagram. The white LED module 14 is dimmed so that it exists within the range surrounded by the square connecting the four points (0.3369), (0.3630, 0.3550), and (0.3660, 0.3820).

As described above, the lighting fixture 1 of the present embodiment emits blue light from the light guide plate 17 by the blue LED module 18 and white light from the diffuser plate 13 by the white LED module 14 through the window. You can reproduce the appearance of the sky you can see and the sunlight around the window. Further, by setting the brightness ratio between the brightness of the light emitted from the light guide plate 17 and the brightness of the light emitted from the diffuser plate 13 and the chromaticity of the light emitted from the diffuser plate 13 as described above, from the sky in the lighting fixture 1. The reproducibility of the light can be improved.

Although the description has been made on the premise that the lighting fixture 1 is attached to the ceiling C in the first embodiment, the lighting fixture 1 may be installed on the wall in the room. However, in that case, the white LED module 14 is made L-shaped in a plan view. In line with this, with respect to the diffuser plate 13, of the four side surfaces, two adjacent surfaces are designated as light emitting surfaces 13-1, and the other two surfaces are designated as non-light emitting surfaces 13-2. Other configurations are the same as those in the first embodiment. As a result, even when the lighting fixture 1 is installed on the wall in the room as in the case where the lighting fixture 1 is attached to the ceiling C, a blue sky with a sense of depth is seen through the window frame in the sun or shade illuminated by sunlight. It is possible to produce a visual effect like looking at. Further, the shape of the luminaire 1 is not limited to a rectangle, and may be a square box shape.

Further, in the first embodiment, the first to fifth power supply devices 31a to 31e are provided for each LED, but the present invention is not limited to this. For example, the power supply device for the white LED 181 and the blue LED 182 of the blue LED module 18 may be shared. As a result, the number of parts can be further reduced, the cost can be reduced, and the luminaire 1 can be downsized.

Further, in the first embodiment, the control circuits of the white LED 181 and the blue LED 182 are shared, and the same dimming signal is used for dimming, but the present invention is not limited to this. The white LED 181 and the blue LED 182 may each have a separate control circuit and are controlled by a separate dimming signal.

Further, in the above-described embodiment, first, the amount of light of the green LED 183 is reduced, and then the amount of light of the white LED 181 and the blue LED 182 is reduced in two stages, but the control is not limited to this. For example, it may be a two-step control in which the amount of light of the white LED 181 and the blue LED 182 is reduced and then the amount of light of the green LED 183 is reduced. Further, the control of the white LED 181 and the blue LED 182 and the green LED 183 is not limited to those described above, and the x value and / or y value in the CIE chromaticity coordinates are used depending on the desired sky color. May be changed to the minus side or the plus side.

Further, in the above-described embodiment, the blue LED module 18 has a configuration including a plurality of white LEDs 181 and a blue LED 182 and a green LED 183, but if it emits light containing a blue light component, this is used. It is not limited to. For example, the blue LED module 18 may have a configuration having any of the following LEDs (1) to (7).
(1) Blue LED, white LED, green LED, and amber LED.
(2) Light blue LED, green LED, and amber LED.
(3) Light blue LED and green LED.
(4) White LED (8000-7000K) and amber LED.
(5) Light blue LED and amber LED.
(6) Light blue LED only.
(7) White LED (8000-7000K) only.

1 lighting fixture, 10 light source unit, 11 flange, 13 diffuser, 13-1 light emitting surface, 13-2 non-light emitting surface, 14 white LED module, 15 module holding part, 15-1 mounting flange, 16 lower guide plate , 16-3 protrusion, 17 light source plate, 17-1 end face, 17-2 end face, 18 blue LED module, 18-1 through hole, 19 upper guide plate, 21 packing, 22 packing, 23 insulation part, 24 module Holding part, 25 fixing member, 25-1 protrusion, 26 light guide plate cover, 27 top cover, 31 power supply device, 31a first power supply device, 31b second power supply device, 31c third power supply device, 31d fourth power supply device, 31e 5th power supply, 32 dimming unit, 32a 1st control circuit, 32b 2nd control circuit, 32c 3rd control circuit, 32d 4th control circuit, 33 voids, 50 fixture body, 51 main surface, 51-1 volt Hole, 51-2 wire hole, 52 side surface, 53 mounting bracket, 54 terminal block, 61 nut, 101, 102, 103, 104 prototype, 140 board, 141, 142 white LED, 180 board, 181 white LED, 182 blue LED , 183 green LED, B hanging bolt, C ceiling, H embedded hole.

Claims

An LED module for blue that emits light containing a blue light component,
A light guide plate that diffuses the light of the blue LED module to emit surface light,
A white LED module that emits white light,
A diffuser plate that is arranged so as to intersect the light guide plate and diffuses the white light of the white LED module.
The blue LED module is dimmed to reproduce the color of the sky, and the white LED module is dimmed to reproduce the sunlight.
The dimming unit is used for the white LED module or the blue LED module so that the ratio of the brightness of the light emitted from the light guide plate to the brightness of the light emitted from the diffuser plate is 1: 5.8 to 1:13. Lighting equipment that dims the LED module.
The dimming unit is used for the white LED module or the blue LED module so that the ratio of the brightness of the light emitted from the light guide plate to the brightness of the light emitted from the diffuser plate is 1: 5.8 to 1: 7. The lighting fixture according to claim 1, wherein the LED module is dimmed.
In the dimming unit, the chromaticity of light emitted from the diffuser is (0.3376, 0.3616), (0.3366, 0.3369) in the xy coordinate system (x, y) of the CIE chromaticity diagram. ), (0.3630, 0.3550), (0.3660, 0.3820) The white LED module is dimmed so as to be within the range surrounded by the square connecting the four points. Lighting equipment described in.
The lighting fixture according to any one of claims 1 to 3, wherein the white LED module has two types of white LEDs having different color temperatures.
The lighting fixture according to any one of claims 1 to 4, wherein the blue LED module has at least two types of LEDs that emit light of different colors.
The lighting fixture according to any one of claims 1 to 5, wherein the dimming unit dims the blue LED module according to the time.
The lighting fixture according to any one of claims 1 to 6, wherein the dimming unit dims the blue LED module according to the season.
The lighting fixture according to any one of claims 1 to 7, wherein the white LED module emits white light from three directions.