lighting fixtures

Abstract

To provide a lighting fixture capable of adjusting illuminance in front of eyes by a light control film without changing illuminance of a floor surface and having small luminance variation in a vertical direction of the light control film.SOLUTION: The lighting device (1) includes a dimming film (33) stretched in a vertical direction and capable of switching between a state of transmitting light and a state of reflecting light, and light sources (3, 3 ') configured to irradiate surfaces of the dimming film with light, wherein the surfaces of the dimming film have a visible range (7) that is visible when facing from a lateral direction, a vertical length from an upper side 7c to a lower side 7d of the visible range is 50 to 270mm, and the light sources obliquely irradiate the visible range of the dimming film with light via a spatial path (8).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a lighting fixture. [Background technology]

[0002] Among lighting fixtures, there is known one in which a reflector is attached to the underside of a light source attached to the ceiling, and the light emitted from the light source to the reflector is reflected by the reflector. By reflecting light with the reflector, it is possible to improve the sense of spaciousness and brightness of an indoor space and create a calm atmosphere (see, for example, Patent Document 1).

[0003] Also, some lighting fixtures are known that have a vertical reflector attached to the underside of the light source, and transmit light irradiated from the light source onto the vertical reflector directly below the vertical reflector, while also reflecting it in the direction of a person's line of sight. By transmitting light directly below the vertical reflector and reflecting it in the direction of the person's line of sight, it is possible to improve the sense of brightness indoors (see, for example, Patent Document 2).

[0004] Here, with conventional lighting fixtures, when adjusting the amount of light (brightness) entering the human eye to suit the indoor environment, for example, it is necessary to adjust the intensity of the light emitted from the light source. For this reason, with conventional lighting fixtures, when adjusting the amount of light entering the human eye, the illuminance on the floor surface changes. Hereinafter, the amount of light entering the human eye may be referred to as "preocular illuminance." Meanwhile, there is a demand for practical application of lighting fixtures that can adjust the preocular illuminance to suit the indoor environment without changing the floor illuminance.

[0005] Furthermore, some lighting fixtures are known to be equipped with a light-control film that can be changed between a frosted (reflective) state and a clear (transmissive) state (see Figure 6B of Patent Document 3 and Figure 3 of Patent Document 4). The use of such light-control films may enable adjustment of the illuminance in front of the eye without changing the illuminance on the floor. However, these lighting fixtures do not mention anything about the luminance variation (standard deviation) in the direction away from the light source (the Z direction, which is the up-and-down direction, in Patent Document 3, and the X direction, which is the left-and-right direction, in Patent Document 4). The reason for this is likely to be that these lighting fixtures have a light guide plate aligned with the light-control film, and light from the light source is irradiated onto the light-control film via the light guide plate, so that luminance variation is small to begin with and does not pose a problem.

[0006] Patent Document 5 discloses that by adjusting the spacing between LED chips, the photosynthetic photon flux density (PPFD) variation (standard deviation / average value) can be set to 0.5 or less at a position 50 mm away from the LED chip, thereby controlling the variation in light (5000K) (paragraphs 0022, 0027, Table 1). However, Patent Document 5 only reports measurements taken at 24 points on the xy plane 50 mm away from the LED chip (paragraph 0105), and does not cover the brightness variation in the vertical direction. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Utility Model Application Publication No. 5-6525 [Patent Document 2] Japanese Patent Application Laid-Open No. 2001-291404 [Patent Document 3] US Patent Application Publication No. 2015 / 0219836 [Patent Document 4] Japanese Patent Application Laid-Open No. 2014-130692 [Patent Document 5] Patent No. 6953461 Summary of the Invention [Problem to be solved by the invention]

[0008] The inventors of the present application have been considering attaching a light control film vertically to the underside of a light source (as in Patent Documents 3 and 4) and irradiating light from the light source to the light control film via a spatial path (as in Patent Documents 1 and 2).When they actually prototyped such a lighting fixture and measured the brightness, they found that unless influencing factors are controlled, brightness variation in the vertical direction in the frosted (reflective) state becomes large at commonly used color temperatures (2700 to 4500K) (see the comparative example below).One of the reasons for this is thought to be that a light guide plate like that in Patent Documents 3 and 4 is not used.

[0009] Therefore, an object of the present invention is to provide a lighting fixture that can adjust the illuminance in front of the eye using a light control film without changing the illuminance on the floor surface, and that has little variation in brightness in the vertical direction of the light control film. [Means for solving the problem]

[0010] [1] A light-control film stretched in the vertical direction that can be switched between a light-transmitting state and a light-reflecting state; a light source that irradiates light onto the surface of the light management film; The surface of the light control film has a visibility range that can be seen when viewed from the side, The vertical length from the top to bottom of the visible range is 50 to 270 mm, A lighting fixture in which the light source irradiates light obliquely through a spatial path into the visible range of the light control film.

[0011] [Effect] The light source irradiates light obliquely onto the visible range of the light control film via a spatial path, and the vertical length of the visible range of the light control film is 50 to 270 mm (preferably 100 to 250 mm), thereby reducing the vertical luminance variation of the light control film and ensuring a certain level of illuminance in front of the eye. If this length exceeds 270 mm, the vertical luminance variation of the light control film increases. If this length is less than 50 mm, the area of ​​the visible range becomes small and the illuminance in front of the eye tends to decrease.

[0012] [2] A lighting fixture according to [1], wherein the light-controlling film is supported by a support panel through which light emitted from the light source is transmitted in the thickness direction of the panel without entering through the edge of the panel.

[0013] [3] The center of the light source is It is 10 to 80 mm above the top edge of the visible range and 10 to 50 mm to the side, or The lighting fixture according to [1] or [2], which is spaced 10 to 80 mm downward and 10 to 50 mm laterally from the lower edge of the visible range.

[0014] [4] The lighting fixture according to any one of [1] to [3], wherein the light source is capable of changing the color temperature at least within a range of 2700 to 4500K.

[0015] [5] The lighting fixture according to any one of [1] to [4], wherein a light diffusion transmission panel that diffuses light emitted from the light source and transmits the light in the panel thickness direction is provided midway along the spatial path.

[0016] [6] The lighting fixture according to [5], wherein the light diffusion transmitting panel is spaced 0 to 70 mm above the upper edge of the visible range and 0 to 40 mm laterally.

[0017] [7] The lighting fixture according to any one of [1] to [6], wherein the visible range is rectangular and the length from the left side to the right side of the visible range is 800 mm or more.

[0018] [8] When the light is irradiated into the visible range of the light-controlling film that has been set to a light-reflecting state, the standard deviation and average (hereinafter referred to as the "upper and lower average") of the average brightness at the measurement positions A1, B1, and C1, the average brightness at the measurement positions A2, B2, and C2, and the average brightness at the measurement positions A3, B3, and C3 are calculated, and the standard deviation / upper and lower average is 1 or less (preferably 0.8 or less). [7] A lighting device. Note Measurement position A1 is 31 mm below the top edge in the center between the left and right edges, measurement position A3 is 31 mm above the bottom edge, and measurement position A2 is the center between measurement positions A1 and A3 Measurement position B1 is 280 mm inside from the left side, 31 mm below the top side, measurement position B3 is 31 mm above the bottom side, and measurement position B2 is the center between measurement positions B1 and B3 Measurement position C1 is 280 mm inside from the right side, 31 mm below the top side, measurement position C3 is 31 mm above the bottom side, and measurement position C2 is the center between measurement positions C1 and C3

[0019] [9] The light source is capable of changing the color temperature at least within the range of 2700 to 4500K, and the standard deviation / upper and lower averages are all 1 or less (preferably 0.8 or less) when irradiating light with color temperatures of 2700K, 3100K, 3800K and 4500K, respectively. [8] A lighting device as described in [8].

[0020]

[10] including a casing; The visibility range is extended from the casing, The lighting fixture according to any one of [1] to [9], wherein the light source is disposed inside a casing. [Effects of the Invention]

[0021] According to the present invention, it is possible to provide a lighting fixture that can adjust the illuminance in front of the eye using a light control film without changing the illuminance on the floor surface, and that has little variation in brightness in the vertical direction of the light control film. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a perspective view showing a lighting fixture according to a first embodiment. [Figure 2] FIG. 2 is a front view showing the lighting fixture with a part cut away. [Figure 3] FIG. 3 is a cross-sectional view taken along line III-III in FIG. [Figure 4] Figure 4(a) is an explanatory diagram of the same lighting fixture when light from the light source is transmitted through the light control film, and (b) is an explanatory diagram of the same lighting fixture when light from the light source is reflected by the light control film. [Figure 5] Figure 5 explains how to measure the brightness of the synchronous film using the same lighting fixture, (a) is a side view and (b) is a front view. [Figure 6] FIG. 6 is a side view (a) and a front view (b) illustrating a method for measuring the brightness of the light control film of the lighting fixture of Example 2. [Figure 7] FIG. 7 is a side view (a) and a front view (b) illustrating a method for measuring the brightness of the light control film of a lighting fixture of a comparative example. [Figure 8] FIG. 8 is a cross-sectional view of a modification of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0023] 1. Light-controlling film The light control film is not particularly limited as long as it can be switched between a light transmitting state and a light reflecting state. The type of light control film is not particularly limited, but examples include PDLC (Polymer Dispersed Liquid Crystal), PNLC (Polymer Network Liquid Crystal), GHLC (Guest Host Liquid Crystal), SPD (Suspended Particle Device), electrochromic, gaschromic, etc. In particular, PDLC, PNLC, and GHLC are preferred in the present invention because the liquid crystal molecules dispersed in the polymer are arranged irregularly when no voltage is applied, resulting in an opaque (milky white, frosted) display, and when voltage is applied, they are oriented in the direction of the electric field, resulting in a transparent (clear) display.

[0024] The light control film may be switched to a normal mode in which it reflects light when the power is off and transmits light when the power is on, or to a reverse mode in which it transmits light when the power is off and reflects light when the power is on. From the viewpoint of energy saving, the normal mode is preferable when the time in which the light is reflected is longer than the time in which the light is transmitted, and the reverse mode is preferable when the time in which the light is transmitted is longer than the time in which the light is reflected.

[0025] The state in which light is transmitted is not particularly limited, but a transparent state can be exemplified. The state in which light is reflected is not particularly limited, but examples include a milky white state and a colored state.

[0026] The shape of the light control film (particularly the shape of the visible range) is not particularly limited, but examples include a rectangle, a semicircle, and a semi-ellipse.

[0027] 2. Support panel The support panel is such that light emitted from the light source does not enter from the panel end surface but passes through in the panel thickness direction. The material of the support panel is not particularly limited, but examples include resin, glass, etc. As the resin, highly transparent acrylic, polycarbonate, polyethylene terephthalate, etc. are preferred. The thickness of the support panel is not particularly limited, but can be exemplified as 1 to 10 mm. The way in which the support panel supports the light-control film is not particularly limited, but examples include a mode in which the light-control film is provided on one surface of the support panel, a mode in which the light-control film is provided on both surfaces of the support panel, and a mode in which the light-control film is sandwiched between a pair of support panels.

[0028] 3.Light source The light source is not particularly limited, but examples include a light emitting diode (LED) and a fluorescent tube. The color temperature of the light emitted by the light source is not particularly limited and can be appropriately selected within the range of, for example, 2000 to 10000K. The light source is preferably one whose color temperature can be changed, more preferably one whose color temperature can be changed at least within the range of 2700 to 4500K. It is also preferable that the light source contains a large amount of melatonin-suppressing light (480 nm) components.

[0029] The center of the light source is preferably 10 to 80 mm above the upper edge of the visible range and 10 to 50 mm laterally, or 10 to 80 mm below the lower edge of the visible range and 10 to 50 mm laterally. This is because the light from the light source is more likely to travel through a spatial path and be obliquely irradiated onto the visible range of the light control film, and also because the brightness variation in the vertical direction of the light control film is more likely to be reduced.

[0030] 4.Light diffusion transmission panel A light-diffusing, transmissive panel diffuses light emitted from a light source and transmits it in the thickness direction of the panel, thereby suppressing glare by making the glare of the light source less noticeable, and irradiating the light over a wide area of ​​the light-control film. The light diffusion transmission panel is not particularly limited, but examples thereof include a semi-transparent milky white panel, a panel with a textured surface, etc. Examples of the textured surface include fine textures like frosted glass, textures like molded glass, and textures like prisms. The material of the light diffusion transmission panel is not particularly limited, but examples thereof include resin, glass, etc. Examples of resin include the above-mentioned acrylic, polycarbonate, polyethylene terephthalate, etc.

[0031] The light diffusion transmission panel is preferably spaced 0 to 70 mm above the upper edge of the visible range and 0 to 40 mm laterally. This is because light that is diffused and transmitted through the light diffusion transmission panel is likely to be obliquely irradiated onto the visible range of the light control film via a spatial path, and also because this tends to reduce the brightness variation in the vertical direction of the light control film. [Example]

[0032] Next, specific embodiments of the present invention will be described with reference to the drawings. Note that the shapes, dimensions, materials, quantities, etc. of the various parts in the embodiments are merely examples and may be modified as appropriate without departing from the spirit and scope of the invention.

[0033] [Example 1] The lighting fixture 1 of the first embodiment shown in FIGS. 1 to 5 is, for example, a light that is attached to a ceiling 100 and illuminates an interior space 102. The lighting fixture 1 includes a casing 11, a power supply unit 12, a pair of light sources 3, 3′, a pair of light diffusion transmission panels 16, 16′, and a brightness adjustment unit 4.

[0034] <Casing> The casing 11 is attached to, for example, a ceiling 100. The casing 11 has a casing main body 14, a casing decorative portion 15, a light source support portion 13, a panel support portion 17, an umbrella portion 10, and brightness adjustment portion support portions 18 and 19.

[0035] The casing body 14 is disposed above the ceiling 100 through an opening 103 in the ceiling 100. The casing body 14 has a cross section in the width direction formed into a substantially rectangular frame, extends in the longitudinal direction, and has external dimensions of 114 mm width x 94 mm height x 1180 mm length. The decorative casing part 15 is provided at the bottom of the casing main body 14 and is arranged indoors 102 along the surface 100a of the ceiling 100. The decorative casing part 15 is arranged with its surface facing the indoors 102. The decorative casing part 15 has a pair of openings 21. The pair of openings 21 are formed on both sides of the brightness adjustment part 4 (described later) in the width direction and extend in the longitudinal direction.

[0036] The light source support portion 13 is provided at the upper part inside the casing body 14, and supports the light sources 3, 3' as will be described later. The umbrella portion 10 is made up of a pair of inclined plates that are provided so as to expand from the light source support portion 13 to the opening 21 in an umbrella-like cross section. The panel support portion 17 is provided at the middle portion in the height direction inside the casing body 14, and supports the light diffusion transmission panel 16 as will be described later. The brightness adjustment unit support parts 18 and 19 are provided in the center of the width direction inside the casing main body 14, and sandwich the brightness adjustment unit 4 therebetween as will be described later.

[0037] <Power supply unit> The power supply unit 12 is housed in a casing body 14 and is provided on a top portion 14 a of the casing body 14 . The power supply unit 12 separately controls the current flowing through the low color temperature LED and the current flowing through the high color temperature LED of each light source 3, 3' described below, and by changing both currents, the color temperature of the mixed light of the low color temperature LED and the high color temperature LED can be changed within the range of 2700 to 5000K. The power supply unit 12 also controls the switching between energization and de-energization of the light control film 33 .

[0038] <Light source> The light source emits light through a spatial path 8 and obliquely downwards onto a visible range 7 of a light control film 33, which will be described later. A pair of light sources (first light source 3 and second light source 3') are provided on both sides of brightness adjustment unit 4. In this embodiment, each of the light sources 3, 3' is formed by arranging 72 low color temperature LEDs emitting light with a color temperature of 2700 K and 72 high color temperature LEDs emitting light with a color temperature of 5000 K alternately in a straight line on a substrate 24. The total length of the arrangement is 1080 mm, extending in the longitudinal direction of the casing body 14. The power consumption is 0.5 W per LED, so that each light source 3, 3' (144 LEDs each) consumes 72 W. The instantaneous luminous flux of each light source 3, 3' is about 7000 lm. Each of the light sources 3, 3' can change the color temperature of the mixed light of the low color temperature LED light and the high color temperature LED light within a range of at least 2700 to 5000K by controlling the power supply unit 12 as described above.

[0039] The light sources 3, 3' are housed in a casing body 14 and attached to the light source support portion 13 described above at a base plate 24. The light sources 3, 3' are positioned above the ceiling 100, above the light diffusing transmission panels 16, and opposed to the light diffusing transmission panels 16, 16'. The light sources 3, 3' are provided on both sides of the brightness adjusting section 4, which will be described later, with a gap therebetween in the width direction.

[0040] <Light diffusion transmission panel> The light diffusion transmission panels 16, 16' are provided in the middle of the spatial path 8, and diffuse the light emitted from the light sources 3, 3' and transmit it in the panel thickness direction. A pair of light diffusion transmission panels (a first light diffusion transmission panel 16 and a second light diffusion transmission panel 16′) are provided on both sides of the brightness adjustment section 4. In this embodiment, semi-transparent milky acrylic plates (trade name "Acrylite EX432 (plate thickness: 2.0 mm)" manufactured by Mitsubishi Chemical Corporation) are used as the light diffusion transmission panels 16, 16'. Each of the light diffusion transmission panels 16, 16' is housed in the casing main body 14, attached to the panel support portion 17 described above, and provided on the inner side above the casing decorative portion 15.

[0041] The umbrella portion 10 of the casing 11 is installed below each of the light diffusion transmitting panels 16, 16'. The effective portion of the light diffusion transmitting panels 16, 16' that can transmit light is the portion that corresponds to the upper opening of the umbrella portion 10, and the edge of the light diffusion transmitting panels 16, 16' is hidden behind the upper end of the umbrella portion 10.

[0042] <Brightness adjustment section> The brightness adjustment unit 4 is disposed between the light sources 3, 3' in the width direction and is provided in the casing main body 14. The brightness adjustment unit 4 is formed into a substantially rectangular shape in a side view. The brightness adjustment unit 4 is supported (fixed) in a state where an upper end portion 4a of the brightness adjustment unit 4 is sandwiched between a pair of support portions 18, 19 by fixing members such as a plurality of bolts 26 and a plurality of nuts 27. The upper end portion 4a is located below the pair of light sources 3, 3'. The fixing members such as the plurality of bolts 26 and a plurality of nuts 27 are located above the light diffusion transmission panels 16, 16'. In other words, the brightness adjustment unit 4 is fixed to the casing main body 14 at an upper position in the direction opposite to the direction in which the brightness adjustment unit 4 protrudes downward, relative to the light diffusion transmission panels 16, 16'. In this state, the brightness adjustment unit 4 is disposed in a direction perpendicular to the line connecting the light diffusion transmission panels 16, 16'. The brightness adjustment unit 4 projects vertically downward from between the light diffusion transmission panels 16, 16' and hangs down from the casing main body 14 into the indoor space 102.

[0043] The brightness adjustment unit 4 has a first section 5 disposed within the casing main body 14 (above the bottom surface of the casing decorative section 15) and a second section 6 protruding from the casing main body 14 (below the bottom surface of the casing decorative section 15). The distance (length) from one end 6a to the other end 6b in the longitudinal direction of the second section 6 is longer than the distance (length) from one end 5a to the other end 5b in the longitudinal direction of the first section 5.

[0044] The brightness adjusting unit 4 includes a support panel 32 and a light control film 33. The support panel 32 is formed, for example, in a substantially rectangular shape from a transparent acrylic plate with a thickness of 5 mm that allows light to pass through. The acrylic plate has high transparency, and the transparency can be increased when the light control film 33 is energized. Therefore, light irradiated onto both sides 33a of the light control film 33 can be transmitted through the light control film 33 satisfactorily.

[0045] The light control film 33 is formed on one surface 32a of the support panel 32. Therefore, the single support panel 32 can stably support the light control film 33 in a stretched state in the vertical direction, and can also stably hang down between the light sources 3, 3' into the indoor space 102. Furthermore, compared to when the light control film 33 is formed on both surfaces of the support panel 32, more light emitted from the pair of light sources 3, 3' can be transmitted. Here, the light emitted from the pair of light sources 3, 3' is irradiated onto both surfaces 33a of the light control film 33.

[0046] In this embodiment, a PDLC-type light control film (trade name "Kasmy" manufactured by Be-Cat) is used for the light control film 33. When this light control film 33 is in an ON state, with voltage applied from the power supply unit 12 to the liquid crystal molecules in the film, the liquid crystal molecules align in the direction of the electric field, allowing light to pass through, making it transparent (clear). When this light control film 33 is in an OFF state, with no voltage applied from the power supply unit 12, the liquid crystal molecules are irregularly aligned, scattering light, making it milky white (opaque, frosted), and reflecting light (although some light is transmitted). In other words, the light control film 33 can be instantly switched between a transparent state and a milky white state by switching the power supply unit 12 between energized (ON) and de-energized (OFF).

[0047] In the second region 6 of the brightness adjustment unit 4, the surface of the light control film 33 has a viewable range 7 that can be seen when viewed perpendicularly from the side (see FIG. 2). The viewable range 7 is rectangular, and the vertical length from the top side 7c to the bottom side 7d of the viewable range 7 is 186 mm, and the horizontal length from the left side 7a to the right side 7b is 1200 mm. In the second portion 6 of the brightness adjusting section 4, the support panel 32 is slightly larger (by a few mm) than the visible range 7 of the light control film 33, so the one end 6a and the other end 6b are the respective ends of the support panel 32.

[0048] <Positional relationship between the light source, light diffusion transmission panel, and light control film> (See Figure 3) The center of the first light source 3 is spaced 55 mm upward and 25 mm horizontally (to the left) from the upper side 7c of the visible range 7 of the light control film 33. The center of the second light source 3' is spaced 55 mm above the upper side 7c of the visible range 7 and 30 mm to the side (right). The above-mentioned effective portion of the first light diffusion transmission panel 16 is spaced 31 mm above the upper side 7c of the visible range 7 and 17 mm laterally (to the left). The above-mentioned effective portion of the second light diffusing transmission panel 16 is spaced 31 mm above the upper side 7c of the visible range 7 and 22 mm to the side (right).

[0049] In addition, each of the above components (light sources 3, 3', light diffusion transmission panels 16, 16', support panel 32, dimming film 33, etc.) can be changed as appropriate, and may be changed to, for example, those exemplified in the [Form for implementing the invention].

[0050] <Switching the state of the light-control film> Next, an example of an operation for switching the light control film between a light transmitting state and a light reflecting state will be described with reference to FIG. When the power supply unit 12 applies electricity to the dimming film 33, making it transparent and allowing light to pass through, and then the power supply unit 12 applies electricity to the pair of light sources 3, 3', as shown in Figure 4(a), light 40 from the first light source 3 and light 40' from the second light source 3' are irradiated onto both surfaces 4b of the brightness adjustment unit 4 and pass through the dimming film 33 and the support panel 32. When the power supply unit 12 de-energizes the light control film 33, turning it into a milky white state that reflects light, and then the power supply unit 12 applies electricity to the pair of light sources 3, 3', as shown in Figure 4(b), light 40 from the first light source 3 is reflected by one surface 33a of the light control film 33, and light 40' from the second light source 3' is reflected by the other surface 33a of the light control film 33.

[0051] <Measurement of brightness when light-control film reflects light> The lighting fixture 1 of Example 1 configured as described above was attached to the ceiling of a darkroom in which external light was blocked by a blackout curtain, as shown in FIG. 5, and the luminance of the surface of the light-control film 33 was measured as follows when light was irradiated onto the light-reflecting film 33.

[0052] 5(a), an illuminance meter 51 (manufactured by Konica Minolta, Inc., product name "CL-200A") was placed at a position 2000 mm downward from the underside of the decorative casing 15. A 360° camera 52 (a 360° camera manufactured by Ricoh, product name "THETA Z1") was placed at a position 1000 mm laterally (to the left) from the left surface of the light control film 33. The power supply unit 12 de-energized the light control film 33, causing the film 33 to reflect light in a milky white state, and then the power supply unit 12 energized the pair of light sources 3, 3', illuminating both sides of the light control film 33 to generate brightness. At this time, under the control of the power supply unit 12, the light sources 3, 3' were made to emit light with color temperatures of 2700K, 3100K, 3800K, and 4500K in a switching manner, and the actual color temperature was measured and confirmed with the illuminance meter 51, and the illuminance directly below the lighting fixture was measured, and the power supply unit 12 adjusted the current so that the illuminance at each color temperature was unified.

[0053] The surface of the light-control film 33 (visible range 7) that produced the above-mentioned luminance was photographed with a 360° camera 52. As shown in Figure 5(b), the following nine measurement positions, A1-A3, B1-B3, and C1-C3, were set within the visible range 7, and the luminance at each measurement position within the visible range 7 was measured using image analysis software (product name "EALAPS-Omni" manufactured by Visual Technology Laboratory Co., Ltd.) based on the captured images. The standard deviation and average (hereinafter referred to as the "upper and lower average") of the average luminance at measurement positions A1, B1, and C1, the average luminance at measurement positions A2, B2, and C2, and the average luminance at measurement positions A3, B3, and C3 were calculated, and the standard deviation / upper and lower average was also calculated. The results are shown in Table 1. Note Measurement position A1 is 31 mm below the top edge in the center between the left and right edges, measurement position A3 is 31 mm above the bottom edge, and measurement position A2 is the center between measurement positions A1 and A3 Measurement position B1 is 280 mm inside from the left side, 31 mm below the top side, measurement position B3 is 31 mm above the bottom side, and measurement position B2 is the center between measurement positions B1 and B3 Measurement position C1 is 280 mm inside from the right side, 31 mm below the top side, measurement position C3 is 31 mm above the bottom side, and measurement position C2 is the center between measurement positions C1 and C3

[0054] [Table 1]

[0055] As shown in Table 1, when irradiated with light of 2700K, 3100K, 3800K, and 4500K, the standard deviation / average above and below was 0.8 or less. In addition, when the standard deviation / average above and below of the average of the results for each of these color temperatures (hereinafter referred to as the "color average") was calculated, it was also found to be 0.8 or less. These results confirmed that the brightness variation in the vertical direction of the light control film 33 is small.

[0056] Furthermore, when the standard deviation / average of the upper and lower parts (A3, B3, C3) was calculated from the color average, excluding the color average of the lower part, it was found to be less than 0.5. This suggests that the luminance variation can be further reduced by further reducing the vertical length of the visible range 7 from 186 mm (to 100 mm, for example). However, if the vertical length is reduced to less than 50 mm, the area of ​​the visible range becomes smaller, which tends to reduce the illuminance in front of the eye.

[0057] <Measurement of brightness when light is transmitted through light control film> When light is irradiated onto the light control film 33 in a light-transmitting state, the brightness of the surface of the light control film 33 is so low that it is difficult to recognize, so the variation in brightness in the vertical direction does not pose a problem. Just to be sure, light was irradiated onto the light control film 33 in a light-transmitting state, and the brightness of the light control film 33 was measured using the same method as in Figure 5, and the brightness at each measurement position was 0.2 to 2 cd / m 2 The degree of variation was low, and the standard deviation / average was less than 0.8.

[0058] The lighting device 1 of the first embodiment provides the following effects. (a) By making the light-adjusting film 33 transparent so that light passes through, the light 40 irradiated onto the light-adjusting film 33 passes through the light-adjusting film 33, reducing the illuminance in front of the eyes and making it possible to avoid being aware of the brightness adjustment unit 4. (i) By making the dimming film 33 milky white and reflective, the light 40 irradiated onto the dimming film 33 is reflected by the dimming film 33, increasing the illuminance in front of the eyes and improving the sense of spaciousness and brightness of the indoor space. (C) In the above (A) and (B), the illuminance on the floor surface can be maintained almost unchanged by not changing the intensity of the light 40 emitted from the light source 3. In other words, the illuminance in front of the eyes can be adjusted without significantly changing the illuminance on the floor surface. (D) The light sources 3, 3' emit light obliquely through the spatial path 8 onto the visible range 7 of the light control film 33, and the vertical length of the visible range 7 is 270 mm or less, so in (A) above, there is little variation in brightness in the vertical direction of the light control film 33. In addition, because the vertical length of the visible range 7 is 50 mm or more, a certain level of illuminance in front of the eyes can be ensured. (E) Since LEDs are used as the light sources 3, 3', glare can be a problem if you look directly at them. However, the light-diffusing transparent panels 16, 16' diffuse and transmit the light, so you are less likely to feel glare even if you look directly at the light-diffusing transparent panels 16, 16'. (f) The light-diffusing and transparent panels 16, 16' are located above and further back than the decorative casing portion 15 and are difficult to reach, further reducing the perception of glare. (K) The light sources 3, 3' can change the color temperature within a range of at least 2700 to 5000K, so that lighting that takes into consideration the human circadian rhythm is possible, for example, by emitting light with a high color temperature that suppresses the secretion of melatonin in the morning, and emitting light with a low color temperature that stimulates the secretion of melatonin from the evening onwards. (c) The distance from one end 6a to the other end 6b of the second section 6 is longer than the distance from one end 5a to the other end 5b of the first section 5, so that the second section 6 can be adjusted to the longitudinal length of the casing body 14, and the visible range 7, which can increase the illuminance in front of the eyes, can be expanded.

[0059] [Example 2] Example 2 shown in Figure 6 uses the same lighting fixture 1 as Example 1, and differs from Example 1 only in that only the first light source 3 illuminates one surface of the light control film 33 (the second light source 3' is turned off), and the luminance was measured at measurement positions A1 to A3, B1 to B3, and C1 to C3 of the light control film 33, which was made to a milky white state that reflects light, in the same manner as Example 1, and the average luminance, upper and lower average, and standard deviation / upper and lower average were calculated.The results are shown in Table 2.

[0060] [Table 2]

[0061] As shown in Table 2, when light of 2700K, 3100K, 3800K, and 4500K was irradiated, the standard deviation / average above and below was 0.6 or less. In addition, when the standard deviation / average above and below of the color average results for each of these color temperatures was calculated, it was found to be 0.6 or less. These results confirmed that the brightness variation in the vertical direction of the light control film 33 was small. The reason why the standard deviation / average above and below was smaller than in Example 1 is thought to be because the brightness was lower than in Example 1 when the light control film 33 was illuminated by only the first light source 3.

[0062] Furthermore, when the standard deviation / average of the upper and lower parts (A3, B3, C3) was calculated from the average color value, it was found to be less than 0.3. As in Example 1, this suggests that the brightness variation can be further reduced by further shortening the vertical length of the light control film 33 (visible range 7) from 186 mm (for example, to 100 mm).

[0063] [Comparative Example] The comparative lighting fixture 60 shown in Figure 7 differs from the lighting fixture 1 of Example 1 only in that the vertical length of the visibility range 7 of the dimming film 33 is increased to 372 mm, and the support panel 32 is also increased accordingly; otherwise, it is configured in the same way as the lighting fixture 1 of Example 1.

[0064] Using the same method as in Example 1, the luminance was measured when a pair of light sources 3 and 3' was illuminated on both sides of the light control film 33, which had been rendered milky white and reflective. However, because the vertical length of the visible range 7 was large, the following 18 measurement positions A1 to A6, B1 to B6, and C1 to C6 were set within the visible range 7, and the luminance at each measurement position was measured using a luminance meter 52. The standard deviation and vertical average of the average luminance at measurement positions A1, B1, and C1, the average luminance at measurement positions A2, B2, and C2, the average luminance at measurement positions A3, B3, and C3, the average luminance at measurement positions A4, B4, and C4, the average luminance at measurement positions A5, B5, and C5, and the average luminance at measurement positions A6, B6, and C6 were calculated, and the standard deviation / vertical average was also calculated. The results are shown in Table 3. Note Measurement position A1 is 31 mm below the top edge in the center between the left and right edges, measurement position A6 is 31 mm above the bottom edge, and measurement positions A2-A5 divide the area between measurement positions A1 to A6 into 5 equal parts. Measurement position B1 is 280 mm inside from the left side, 31 mm below the top side, measurement position B6 is 31 mm above the bottom side, and measurement positions B2-B5 divide the area between measurement positions B1 and B6 into 5 equal parts. Measurement position C1 is 280 mm inside from the right side, 31 mm below the top side, measurement position C6 is 31 mm above the bottom side, and measurement positions C2-C5 divide the area between measurement positions C1 to C6 into 5 equal parts.

[0065] [Table 3]

[0066] As shown in Table 3, when irradiated with light of 2700K, 3100K, 3800K, and 4500K, the standard deviation / average above and below was 1.3 or more. In addition, when the standard deviation / average above and below of the color average results for each of these color temperatures was calculated, it was also 1.3 or more. These results confirmed that the brightness variation in the vertical direction of the light control film 33 was large.

[0067] Furthermore, when the standard deviation / upper / lower average was calculated by sequentially excluding the color average in the lower part (A6, B6, C6), the color average in the lower-middle part (A5, B5, C5), the color average in the middle-lower part (A4, B4, C4), and the middle-upper part (A3, B3, C3) from that color average, the standard deviation / upper / lower average calculated by excluding the color average in the lower part (A6, B6, C6) and the color average in the lower-middle part (A5, B5, C5) was less than 1. This suggests that by further shortening the vertical length of the visible range 7 from 372 mm (for example, to 270 mm, preferably 250 mm), it is possible to reduce brightness variation and therefore this can be used as an example.

[0068] The present invention is not limited to the above-described embodiments, and can be embodied by making appropriate modifications within the scope of the invention, for example, as follows. (1) A pair of light sources 3, 3' (or just one of them) is tilted toward the brightness adjustment unit 4 (light control film 33). In this case, only some of the LEDs may be tilted. For example, only the high color temperature LEDs may be tilted toward the brightness adjustment unit 4 (light control film 33) to increase the illuminance in front of the eyes. (2) An angle-changing mechanism (not shown) is provided in the light source support portion 13, and the angle of the pair of light sources 3, 3' (or just one of them) is changed by the angle-changing mechanism. (3) The brightness adjusting section 4 (light control film 33) is provided not vertically but at an angle from the vertical. (4) An angle-changing mechanism (not shown) is provided at the upper end 4a of the brightness adjusting section 4, and the angle of inclination of the brightness adjusting section 4 is changed by the angle-changing mechanism. (5) The brightness adjusting unit 4 may be arranged in a cross shape, a T shape, an L shape, an arc shape, or the like in a plan view. (6) The brightness adjusting unit 4 can be folded parallel to the ceiling 100. (7) The support panel 32 is made of a flexible material such as a vinyl chloride sheet so that the brightness adjusting unit 4 can be stored inside the casing 11.

[0069] (8) The light sources 3, 3' may be positioned above the ceiling 100, or may be positioned below the ceiling 100 and emit light obliquely upward through a spatial path into the visible range 7 of the light control film 33. This can be achieved, for example, by turning the lighting fixture 1 upside down from that in Example 1 and arranging the brightness adjustment unit 4 to protrude upward from the casing 11 and face the ceiling 100. (9) The brightness adjustment unit 4 (light-control film 33) may be positioned so that there is a spatial path 8 on both sides 4b thereof, or may be positioned so that there is a spatial path 8 on only one surface 4b thereof and the other surface 4b is in contact with or close to a wall. This can be achieved by attaching the brightness adjustment unit 4 (light-control film 33) to a wall or by attaching the upper end of the brightness adjustment unit 4 (light-control film 33) to the ceiling 100. As an example, Fig. 8 shows a modification in which the second light source 3', light diffusing and transmitting panel 16' and their peripheral members are omitted from the embodiment in Fig. 3, and the brightness adjustment unit 4 is attached to a wall 104. The light source 3 emits light through a spatial path 8 obliquely to the viewing range 7 on one surface 33a of the light control film 33. (10) In the above embodiment or the modified examples of (1) to (9), the light control film 33 and the light sources 3, 3' may not be fixed to the same casing 11 but may be fixed to separate casings. [Explanation of symbols]

[0070] 1. Lighting equipment 3 First Light Source 3' Second light source 4 Brightness adjustment section 7. View Range 7a Left side 7b Right side 7c top side 7d bottom edge 8 Spatial Path 11 Casing 16. First light-diffusing transparent panel 16' Second light-diffusing transmission panel 21 Opening 32 Support Panel 33 Light control film 100 ceiling 104 Wall

Claims

1. a light-control film stretched in the vertical direction and switchable between a light-transmitting state and a light-reflecting state; a light source that irradiates light onto the surface of the light management film; The surface of the light control film has a visibility range that can be seen when confronted from the side, The vertical length from the top to bottom of the visible range is 50 to 270 mm, The light source irradiates light obliquely through a spatial path into the visible range of the light control film, The visible range is rectangular, and the horizontal length from the left side to the right side of the visible range is 800 mm or more, When the light is irradiated into the visible range of a light-control film that is in a light-reflecting state, the standard deviation and average (hereinafter referred to as the "upper and lower average") of the average luminance at measurement positions A1, B1, and C1, the average luminance at measurement positions A2, B2, and C2, and the average luminance at measurement positions A3, B3, and C3 are calculated, and the standard deviation / upper and lower average is 1 or less. Note Measurement position A1 is 31 mm below the top edge in the center between the left and right edges, measurement position A3 is 31 mm above the bottom edge, and measurement position A2 is the center between measurement positions A1 and A3. Measurement position B1 is 280 mm inside from the left side, 31 mm below the top side, measurement position B3 is 31 mm above the bottom side, and measurement position B2 is the center between measurement positions B1 and B3 Measurement position C1 is 280 mm inside from the right side, 31 mm below from the top side, measurement position C3 is 31 mm above from the bottom side, and measurement position C2 is the center between measurement positions C1 and C3

2. 2. The lighting fixture according to claim 1, wherein the light control film is supported by a support panel through which light emitted from the light source is transmitted in the thickness direction of the panel without being incident on an end surface of the panel.

3. The center of the light source is It is 10 to 80 mm above the upper edge of the visible range and 10 to 50 mm laterally, or 2. The lighting fixture according to claim 1, wherein the light source is spaced 10 to 80 mm downward from the lower edge of the visible range and 10 to 50 mm laterally from the lower edge of the visible range.

4. 2. The lighting fixture according to claim 1, wherein the color temperature of the light source can be changed at least within a range of 2700 to 4500K.

5. 2. The lighting fixture according to claim 1, further comprising a light diffusion and transmission panel disposed in the spatial path for diffusing the light emitted from the light source and transmitting the light in the thickness direction of the panel.

6. 6. The lighting fixture according to claim 5, wherein the light diffusing and transmitting panel is spaced 0 to 70 mm above and 0 to 40 mm laterally from the upper edge of the visible range.

7. 2. The lighting fixture according to claim 1, wherein the light source is capable of changing the color temperature at least within a range of 2700 to 4500K, and the standard deviation / upper and lower averages are all 1 or less when irradiating light with color temperatures of 2700K, 3100K, 3800K, and 4500K, respectively.

8. including a casing, The visibility range is extended from the casing, 8. The lighting device according to claim 1, wherein the light source is disposed within a casing.

9. a light-control film stretched in the vertical direction and switchable between a light-transmitting state and a light-reflecting state; a pair of light sources provided on both sides of the light management film; Both surfaces of the light control film have a visible range that can be seen when facing each other from the side, The vertical length from the top to bottom of the visible range is 50 to 270 mm, A lighting fixture in which a pair of light sources irradiates light obliquely through a spatial path into the visible range of both surfaces of the light-control film.

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