Illumination space and illumination method

Abstract

The invention provides an illumination space with visual anisotropy and an illumination method. An illumination space includes a surface illumination device, and a first space and a second space divided by the surface illumination device, the surface illumination device includes a light guide member that guides light incident from a light source and extracts the light from a light extraction surface, and the second space is illuminated by the light extracted from the light extraction surface. When the brightness of a first object located in the first space is C, the brightness of the light extraction surface is A, the brightness of a second object located in the second space is D, and the brightness of a surface of the light guide member opposite to the light extraction surface is B, (A / C) / (B / D) is greater than 1.

Description

Technical Field

[0001] The invention relates to an illumination space and an illumination method. Background Art

[0002] Conventionally, there is known a surface lighting device that illuminates with light guided inside a light guide plate and extracted from a light extraction surface of the light guide plate.

[0003] Patent Document 1 discloses a lighting device in which a light guide plate is provided with a concavo-convex surface, or a light diffusion film having a light scattering element is disposed on the light guide plate to extract light from the light guide plate.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2019-75352 Summary of the Invention

[0007] Technical problem to be solved by the invention

[0008] However, the lighting device disclosed in Patent Document 1 and the lighting space divided into the first space and the second space by the lighting device do not have visual anisotropy such that the second space can be visually recognized from the first space through the lighting device, and the first space can hardly be visually recognized from the second space through the lighting device.

[0009] An object of the present invention is to provide a lighting space and a lighting method with visually recognizable anisotropy.

[0010] Technical solutions to technical problems

[0011] An illumination space according to one embodiment of the present invention comprises: a surface lighting device; a first space and a second space divided by the surface lighting device, the surface lighting device comprising a light-guiding component for guiding light incident from a light source and extracting light from a light extraction surface, the second space being illuminated by the light extracted from the light extraction surface, and when the brightness of a first object located in the first space is set to C, the brightness of the light extraction surface is set to A, the brightness of a second object located in the second space is set to D, and the brightness of a surface on the opposite side of the light extraction surface in the light-guiding component is set to B, (A / C) / (B / D) is greater than 1.

[0012] Effects of the Invention

[0013] According to the present invention, it is possible to provide an anisotropic lighting space and a lighting method having visual recognition. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1This is a first diagram illustrating an example of a usage scenario of the lighting space according to the embodiment.

[0015] Figure 2 The second diagram shows an example of a usage scenario of the lighting space according to the embodiment.

[0016] Figure 3 It is a front view schematically showing an example of the surface lighting device according to the embodiment.

[0017] Figure 4 yes Figure 3 Cross-sectional view along line IV-IV.

[0018] Figure 5 yes Figure 3 Magnified view of region V in FIG.

[0019] Figure 6 yes Figure 4 Magnified view of area VI in FIG.

[0020] Figure 7 It is a diagram showing an example of an illumination state of the surface lighting device according to the embodiment when viewed from the side.

[0021] Figure 8 It is a diagram showing an example of an illumination state of the surface lighting device according to the embodiment in a plan view.

[0022] Figure 9 This is a diagram showing an example of the result of visually recognizing the first space from the second space.

[0023] Figure 10 This is a diagram showing an example of the result of visually recognizing the second space from the first space.

[0024] Figure 11 1 and 2 are diagrams showing a state of visibility evaluation when viewing a first space from a second space according to an embodiment.

[0025] Figure 12 1 is a diagram showing a state of visibility evaluation when viewing a second space from a first space according to an embodiment.

[0026] Figure 13 1 and 2 are diagrams showing an example of lighting conditions and visibility evaluation results in an embodiment.

[0027] Figure 14 This is a diagram showing an example of the relationship between brightness and visibility evaluation results in Examples. DETAILED DESCRIPTION

[0028] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In each of the drawings, the same components are denoted by the same reference numerals, and repeated descriptions are omitted as appropriate.

[0029] The following embodiments illustrate lighting spaces and lighting methods that embody the technical concepts of this disclosure and are not intended to limit this disclosure to the following embodiments. Unless otherwise specified, the dimensions, materials, shapes, and relative configurations of the components described below are not intended to limit the scope of this disclosure but are intended to be illustrative. Furthermore, the sizes and positional relationships of components shown in the accompanying drawings are sometimes exaggerated for clarity.

[0030] In each of the accompanying drawings, orthogonal coordinates having an X-axis, a Y-axis, and a Z-axis are used as direction representations. The X-axis, the Y-axis, and the Z-axis are approximately orthogonal to each other. The Z direction along the Z-axis represents the normal direction of the main surface of the light-guiding component possessed by the surface lighting device of the embodiment. The direction in which the arrow of the X-axis points is marked as the +X direction, and the direction opposite to the +X direction is marked as the -X direction. The direction in which the arrow of the Y-axis points is marked as the +Y direction, and the direction opposite to the +Y direction is marked as the -Y direction. The direction in which the arrow of the Z-axis points is marked as the +Z direction, and the direction opposite to the +Z direction is marked as the -Z direction. In this specification, observing an object from the Z direction is referred to as a front view. In addition, observing an object from the +Y direction is referred to as a top view. In addition, observing an object from a direction approximately orthogonal to the Z direction and the Y direction is referred to as a side view. However, these directional representations do not limit the directions of the embodiment.

[0031] <Example of Utilization Scenario of Illumination Space 100>

[0032] Reference Figure 1~Figure 2 The usage scenario of the lighting space 100 will be described. Figure 1~Figure 2 1 is a diagram showing an example of a usage scenario of the lighting space 100. Figure 1~Figure 2 As shown, the lighting space 100 includes a surface lighting device 30 and a first space 10 and a second space 20 divided by the surface lighting device 30. Figure 1~Figure 2 In FIG, ceiling 1 represents the ceiling inside the building, and floor 2 represents the floor inside the building.

[0033] exist Figure 1~Figure 2 In the embodiment, the first space 10 and the second space 20 are both inside the building. The surface lighting device 30 is arranged inside the building as a partition, for example. The surface lighting device 30 divides the first space 10 and the second space 20 inside the building. Figure 1 2 shows a situation where an observer U located in the second space 20 visually recognizes a first object M1 located in the first space 10. Figure 2 This shows a situation where an observer U located in the first space 10 visually recognizes a second object M2 located in the second space 20. The first object M1 and the second object M2 are not limited to Figure 1~Figure 2The cylindrical object shown can also be any object existing in space, including people, walls, floors, ceilings of buildings, etc.

[0034] In this embodiment, the surface lighting device 30 illuminates the second space 20 with light extracted from the light extraction surface 315 of the light guide member 31 included in the surface lighting device 30. Figure 1 As shown, if the brightness of the first object M1 located in the first space 10 is set to C and the brightness of the light extraction surface 315 is set to A, as shown in FIG. Figure 2 As shown, assuming that the brightness of the second object M2 located in the second space 20 is D and the brightness of the opposing surface 314 is B, (A / C) / (B / D) is greater than 1. It should be noted that the opposing surface 314 corresponds to the surface of the light guide member 31 opposite to the light extraction surface 315.

[0035] like Figure 1 As shown, when the observer U located in the second space 20 observes the first space 10 through the surface lighting device 30, the observer U can mainly see the light extraction surface 315 with a brightness higher than that of the first object M1, and can hardly see the first object M1. Figure 2 As shown, when an observer U located in the first space 10 observes the second space 20 through the surface lighting device 30, the brightness of the opposing surface 314 is lower than that of the light extraction surface 315, so the observer U can see the second object M2 located in the second space 20. In this way, by using the surface lighting device 30, the illuminated space 100 can have visual anisotropy such that the second space 20 can be seen from the first space 10, while the first space 10 can hardly be seen from the second space 20.

[0036] For example, to improve visibility and visual field, it may be desirable to be able to see the second space 20 from the first space 10. On the other hand, for safety reasons, it may be desirable to prevent the first space 10 from being visible from the second space 20. The lighting space 100 is suitable for situations requiring such anisotropic visual recognition. For example, in this embodiment, a concealing effect can be achieved, where the first space 10 is not visible from the second space 20.

[0037] In this embodiment, from the perspective of ensuring that the lighting space 100 has appropriate visual anisotropy, (A / C) / (B / D) is more preferably 2 or greater. Furthermore, from this perspective, A / C is even more preferably 5 or greater. Furthermore, from this perspective, B / D is particularly preferably 5 or less.

[0038] Furthermore, in this embodiment, if the power supply to the surface lighting device 30 is stopped, the surface lighting device 30 becomes nearly transparent, allowing the second space 20 to be seen from the first space 10, and vice versa. In other words, the surface lighting device 30 can eliminate visual anisotropy by stopping the power supply. It should be noted that the term "transparent" refers to a visible light transmittance of 80% or greater. In this embodiment, the presence or absence of visual anisotropy can be easily switched by simply turning the power supply to the surface lighting device 30 on or off.

[0039] Furthermore, in this embodiment, the surface lighting device 30 can be easily moved, so by moving the surface lighting device 30, a visually anisotropic lighting space 100 can be easily created at any position. As a result, the convenience of the lighting space 100 can be improved and the usage scenarios of the lighting space 100 can be diversified.

[0040] In this specification, brightness refers to the brightness of light emitted from an object when the first object M1, the second object M2, the light extraction surface 315, the opposing surface 314, and other objects are regarded as virtual light sources. The brightness varies depending on the reflectivity of the object, the brightness in the space where the object is located, and the like. In this embodiment, the lighting space 100 can have visually recognizable anisotropy when the condition that (A / C) / (B / D) is greater than 1 in the comprehensive brightness obtained by adding the reflectivity of the object, the brightness in the space, etc. is satisfied. It should be noted that the brightness A to D can be any of the characteristic values ​​such as the maximum value, the minimum value, and the average value in the brightness as long as they are uniform between the brightnesses A to D.

[0041] <Configuration Example of Surface Illumination Device 30>

[0042] Reference Figures 3 to 6 The structure of the surface lighting device 30 will be described. Figure 3 It is a front view schematically showing an example of the surface lighting device 30 . Figure 4 yes Figure 3 Cross-sectional view along line IV-IV. Figure 5 yes Figure 3 Magnified view of region V in FIG. Figure 6 yes Figure 4 Magnified view of area VI in FIG.

[0043] like Figure 3~Figure 4 As shown, the surface lighting device 30 has a light guide member 31. Figure 3~Figure 4 In the example shown, the light guide member 31 is a plate-like member having a substantially rectangular outer shape in a plan view. The light guide member 31 includes a light guide plate 311 and an air cavity film 312 .

[0044] The light guide plate 311 is a plate-like component having a generally rectangular shape when viewed from above. The air cavity film 312 is a film-like component attached to the principal surface 310 of the light guide plate 311. The principal surface 310 is a surface that is generally perpendicular to the thickness direction of the light guide plate 311. Furthermore, the principal surface 310 intersects the side surfaces of the light guide plate 311.

[0045] The light guide plate 311 is formed of a material with high transmittance for visible light. The light guide plate 311 is formed, for example, of an acrylic resin such as polymethyl methacrylate, a polycarbonate resin, a cycloolefin resin, or glass (for example, soda glass, quartz glass, alkali-free glass, or borosilicate glass). The refractive index of the light guide plate 311 is, for example, greater than 1.40 and less than 1.80. It should be noted that, unless otherwise specified, the refractive index refers to the refractive index measured using an ellipsometer at a wavelength of 550 nm. The thickness of the light guide plate 311 can be appropriately set according to the intended use. The thickness of the light guide plate 311 is, for example, greater than 0.05 mm and less than 50 mm.

[0046] The light extraction surface 315 is the surface of the air cavity film 312 opposite to the surface in contact with or close to the main surface 310. The opposing surface 314 is the surface of the light guide member 31 opposite to the light extraction surface 315. Furthermore, the opposing surface 314 is the surface of the light guide plate 311 opposite to the main surface 310.

[0047] exist Figure 3~Figure 4 In the figure, a light source 32 is arranged at a position opposite to the light incident surface 313 corresponding to the side surface of the light guide plate 311. The light source 32 emits light that is incident on the interior of the light guide component 31 through the light incident surface 313. The light source 32 is, for example, a light emitting diode (LED). However, the light source 32 may also include light sources other than light emitting diodes. The configuration position of the light source 32 is not limited to the position opposite to the side surface of the light guide plate 311, and may be arbitrary. The light from the light source 32 may also be incident on the interior of the light guide component 31 through a light guide such as an optical fiber. The light incident surface 313 is not limited to being provided on the side surface of the light guide plate 311, and may also be provided on at least one of a portion of the light extraction surface 315 and a portion of the opposing surface 314.

[0048] The air cavity film 312 includes a plurality of air cavities 331 inside. The air cavity 331 is a hollow portion filled with a gas such as air. Figure 3 In the example shown, the plurality of air cavities 331 are arranged in a staggered grid pattern when viewed from above. Figure 4 In the example shown, the plurality of air cavities 331 are arranged in a straight line along the direction of the main surface 310 in a side view. However, the plurality of air cavities 331 are not limited to Figure 3~Figure 4 The exemplified air cavity can be appropriately changed according to the purpose of the lighting space 100 and the like.

[0049] The air cavity film 312 can be configured as a shaping film, for example. This shaping film can be manufactured, for example, according to the method described in Japanese Patent Application Publication No. 2013-524288. Specifically, the surface of a polymethyl methacrylate film is coated with a varnish (FINECURE RM-64 manufactured by Sanyo Chemical Industries, Ltd.), an optical pattern is embossed onto the varnished film surface, and the varnish is then cured to produce the desired uneven shaping film. The total thickness of the uneven shaping film is, for example, 130 μm.

[0050] exist Figure 3 In the figure, the pitch Px is the distance between the centers of adjacent air cavities 331 in a direction (X direction) substantially perpendicular to the normal direction of the light guide member 31. The pitch Py is the distance between the centers of adjacent air cavities 331 in a direction (Y direction) substantially perpendicular to the normal direction of the light guide member 31 and the direction along the pitch Px.

[0051] like Figure 5 As shown, the air cavity 331 has a generally arcuate shape when viewed from above. The air cavity 331 includes a curved surface portion 331a and a flat surface portion 331b. The curved surface portion 331a corresponds to the curved portion of the arcuate shape when viewed from above. The flat surface portion 331b corresponds to the straight portion of the arcuate shape when viewed from above. The direction in which the straight portion of the arcuate shape extends when viewed from above (e.g., Figure 5 The length of the air cavity 331 in the X direction (in the X direction) is set to L. On the other hand, the direction perpendicular to the direction in which the straight portion of the arcuate shape extends (for example Figure 5 The length of the air cavity 331 in the Y direction (in the Y direction) is W. The direction in which the straight portion of the arcuate shape extends is, for example, the horizontal direction. The direction orthogonal to the direction in which the straight portion of the arcuate shape extends is, for example, the vertical direction.

[0052] like Figure 6 As shown, the air cavity 331 has a roughly triangular shape when viewed from the side. Within this roughly triangular shape, the sides other than the side corresponding to the curved surface portion 331a and the side corresponding to the flat surface portion 331b are referred to as side portions 331c. The length of the air cavity 331 in the direction normal to the light guide member 31 (the Z direction) is denoted by H. The aforementioned length W corresponds to the length of the air cavity 331 in a direction perpendicular to the normal to the light guide member 31 when viewed from the side. Angle θa is the angle formed between the side corresponding to the curved surface portion 331a and side portion 331c when viewed from the side. Angle θb is the angle formed between the side corresponding to the flat surface portion 331b and side portion 331c when viewed from the side.

[0053] exist Figure 3~Figure 4 In the embodiment, light emitted from the light source 32 is incident on the interior of the light guide component 31 through the light incident surface 313 . Figure 4 The incident light Ri into the interior of the light guide member 31 is guided inside the light guide member 31. Figure 4In the example shown, the incident light Ri is guided toward the −Y direction inside the light guide member 31. A portion of the incident light Ri guided inside the light guide member 31 is reflected by the curved surface portions 331a (see FIG. Figure 5~Figure 6 ) is totally reflected toward the +Z direction. Light totally reflected by the curved surface portion 331a passes through the light extraction surface 315 and is extracted from the light guide member 31 as output light Ro. The output light Ro becomes the illumination light for the surface lighting device 30. The air cavity film 312 is an example of a light extraction portion that extracts light guided within the light guide member 31 to the outside of the light guide member 31.

[0054] The directions in which the incident light Ri guided inside the light guide member 31 is totally reflected by the curved surface portion 331a include not only the +Z direction, that is, the normal direction of the light guide member 31, but also directions other than the normal direction of the light guide member 31, for example, directions intersecting the normal direction of the light guide member 31. The emission direction of the outgoing light Ro from the light guide member 31 also includes not only the normal direction of the light guide member 31, but also directions other than the normal direction of the light guide member 31.

[0055] <Example of Illumination State of Surface Illumination Device 30>

[0056] Figure 7-Figure 8 It is a diagram showing an example of the lighting state of the surface lighting device 30. Figure 7-Figure 8 The lighting state of the surface lighting device 30 is expressed by a polar angle. Figure 7-Figure 8 The lighting state in mainly refers to the lighting angle and light amount of the lighting light. Figure 7 Indicates the lighting status when viewed from the side. Figure 8 Indicates the lighting status when looking down.

[0057] exist Figure 7-Figure 8 In the figure, the outgoing light Ro is represented by a roughly elliptical shape. Figure 4 The light shown in FIG. 1 is light extracted from the light extraction surface 315. The reverse-emitted light Ro', represented by the roughly elliptical shape, is light emitted from the opposing surface 314. In other words, the emitted light Ro is light emitted from the surface illumination device 30 toward the +Z direction. The reverse-emitted light Ro' is light emitted from the surface illumination device 30 toward the -Z direction.

[0058] The length of arrow Ro1, which corresponds to the length of the roughly elliptical shape that cuts off the outgoing light Ro along a 90-degree axis, corresponds to the amount of light emitted by the outgoing light Ro in the 90-degree direction. The longer the length of arrow Ro1, the greater the amount of light emitted by the outgoing light Ro. Similarly, the length of arrow Ro1', which corresponds to the length of the roughly elliptical shape that cuts off the reverse-outgoing light Ro' along a 90-degree axis, corresponds to the amount of light emitted by the reverse-outgoing light Ro' in the 90-degree direction. The longer the length of arrow Ro1', the greater the amount of light emitted by the reverse-outgoing light Ro'. Figure 8Corresponding to the top view Figure 7 Diagram of the outgoing light Ro and the reverse outgoing light Ro' in the 90-degree direction.

[0059] like Figure 7 As shown, the length of the arrow Ro1 in the outgoing light Ro is approximately the same as the length of the arrow Ro1' in the reverse outgoing light Ro', so the light amount of the outgoing light Ro is approximately the same as the light amount of the reverse outgoing light Ro'. However, the illumination angle of the outgoing light Ro is different from the illumination angle of the reverse outgoing light Ro'. The illumination angle of the +Z direction side of the outgoing light Ro is approximately 90 degrees. On the other hand, the illumination angle of the -Z direction side of the reverse outgoing light Ro' is approximately 30 degrees. Therefore, as Figure 8 As shown, the light amount of the outgoing light Ro traveling in a direction of approximately 90 degrees is greater than the light amount of the reverse outgoing light Ro' traveling in a direction of approximately 90 degrees.

[0060] exist Figure 1 In the lighting space 100 shown in FIG. 1 , when viewed from the +Z direction side, Figure 7-Figure 8 When the surface lighting device 30 is in the illumination state of , the amount of light Ro emitted from the light extraction surface 315 becomes greater than the amount of light from the first object M1. As a result, the observer U can hardly see the first object M1. On the other hand, Figure 2 In the lighting space 100 shown in FIG. 1 , when viewed from the -Z direction side, Figure 7-Figure 8 When the surface lighting device 30 is in the illumination state of , the amount of light from the second object M2 becomes greater than the amount of light from the opposing surface 314. Thus, the observer U can see the second object M2.

[0061] As a result of in-depth research, it has been found that when viewed from the side, if the surface lighting device 30 illuminates the second space 20 with a light distribution within a polar angle of 90±30 degrees, the observer U in the second space 20 is almost unable to see the first object M1 in the first space 10. On the other hand, when viewed from the side, if the surface lighting device 30 illuminates the first space 10 with a light distribution with a polar angle less than 45 degrees or greater than 135 degrees, the observer U in the first space 10 can see the second object M2 in the second space 20. Therefore, for example, when the surface lighting device 30 illuminates the second space 20 with a light distribution within a polar angle of 90±30 degrees and illuminates the first space 10 with a light distribution with a polar angle less than 45 degrees or greater than 135 degrees, the illuminated space 100 can have anisotropy.

[0062] <Example of Visual Recognition Results in Illumination Space 100>

[0063] Reference Figures 9 and 10 The visual recognition results in the lighting space 100 will be described. Figure 91 is a diagram showing an example of a result of visually recognizing the first space 10 from the second space 20 . Figure 10 1 is a diagram showing an example of a result of visually recognizing the second space 20 from the first space 10 .

[0064] Figure 9 like Figure 1 As shown, a captured image corresponding to the view of the observer U observing the first space 10 from the second space 20 is shown. Figure 9 As shown, the observer U can see the light extraction surface 315 of the light guide member 31 of the surface lighting device 30 but cannot see the first object M1 located on the back side (−Z direction side) of the surface lighting device 30. In other words, the observer U cannot see the first space 10 from the second space 20.

[0065] Figure 10 like Figure 2 As shown, a captured image corresponding to the view of the observer U from the first space 10 to the second space 20 is shown. Figure 10 As shown, the observer U can see the opposing surface 314 of the light guide member 31 of the surface illumination device 30 and can also see the second object M2 located on the back side (+Z direction side) of the surface illumination device 30 through the light guide member 31. In other words, the observer U can see the second space 20 from the first space 10.

[0066] As described above, the lighting space 100 can have visual anisotropy, that is, the second space 20 can be seen from the first space 10 , and the first space 10 can hardly be seen from the second space 20 .

[0067] <Examples, Comparative Examples>

[0068] The following describes specific examples and comparative examples of the lighting space 100. However, the present invention is not limited thereto. In the examples and comparative examples, visibility from the second space 20 to the first space 10 and from the first space 10 to the second space 20 were evaluated under various conditions in which the driving power of the light source 32 in the surface lighting device 30 was varied.

[0069] (Visibility Evaluation Method)

[0070] Figure 11 This is a diagram showing an example of a state of visibility evaluation when the first space 10 is viewed from the second space 20 . Figure 12 1 is a diagram showing an example of a state of visibility evaluation when the second space 20 is viewed from the first space 10 .

[0071] like Figure 11As shown, in the evaluation of visibility from the second space 20 toward the first space 10, the luminance (luminance A) of the light extraction surface 315 of the light guide member 31 in the surface illumination device 30 was measured using a two-dimensional spectroradiometer 200 located in the second space 20. The two-dimensional spectroradiometer 200 used was a 2D spectroradiometer SR 5000 HS manufactured by TOPCON Co., Ltd. Furthermore, the luminance (luminance B) of the first object M1 located in the first space 10 was measured using a luminance meter 300 located in the first space 10. The luminance meter 300 used was a LS-160 luminance meter manufactured by Konica Minolta, Inc. Although the influence of viewing distance is negligible, in this measurement, the two-dimensional spectroradiometer 200 was kept at a distance of at least 1.5 meters from the surface illumination device 30. The luminance meter 300 was kept at a distance of at least 0.3 meters from the first object M1.

[0072] like Figure 12 As shown, in the evaluation of visibility from the first space 10 to the second space 20, the luminance (luminance C) of the facing surface 314 of the light guide member 31 in the surface illumination device 30 was measured using a two-dimensional spectroradiometer 200 placed in the first space 10. Furthermore, the luminance (luminance D) of a second object M2 located in the second space 20 was measured using a luminance meter 300 placed in the second space 20. The two-dimensional spectroradiometer 200 was placed on the opposite side of the luminance A measurement, that is, on the opposite side from the side view and the opposite side from the top view. While the influence of viewing distance is negligible, in this measurement, the two-dimensional spectroradiometer 200 was at least 1.5 meters away from the surface illumination device 30. The luminance meter 300 was at least 0.3 meters away from the second object M2.

[0073] like Figure 11-12 As shown, the lighting space 100 includes a power supply 400 and a variable unit 500. The power supply 400 is a power supply that supplies power to the light source 32. The variable unit 500 varies the power supplied to the light source 32 according to the brightness of at least one of the first object M1 and the second object M2. For example, the variable unit 500 varies the power supplied from the power supply 400 to the light source 32. Figure 11-12 In the visibility evaluation shown, the driving power of the light source 32 is changed by the variable unit 500 , thereby changing the light quantity of the illumination by the surface lighting device 30 .

[0074] The following describes the detailed structure of the surface lighting device 30 in the embodiment.

[0075] Light guide component 31:

[0076] Use a material with a visible light transmittance of 80% or more and a haze value of 5% or less.

[0077] Light guide plate 311:

[0078] A plate-shaped member made of polymethyl methacrylate (PMMA) and having a thickness of 5 mm was used.

[0079] Air cavity film 312:

[0080] Use with Figure 5~Figure 6 The structure of the air cavity 331 is as follows: the length L is 80 μm, the length W is 20 μm, the length H is 10 μm, the angle θa is 49 degrees, and the angle θb is 85 degrees. Figure 3 The pitch Px is 120 μm, the pitch Py is 140 μm, and a plurality of air cavities 331 are arranged.

[0081] (Visibility evaluation results)

[0082] Reference Figure 13 and Figure 14 The evaluation results of visibility are described. Figure 13 1 and 2 are diagrams showing an example of lighting conditions and visibility evaluation results in an embodiment. Figure 14 This is a diagram showing an example of the relationship between brightness and visibility evaluation results in Examples.

[0083] exist Figure 13-14 Examples 1 to 20 and 24 to 28 are examples, and Examples 21 to 23 are comparative examples. Figure 1 As shown, Examples 1 to 23 are cases where the first space 10 is visually recognized from the second space 20. Figure 2 As shown, Examples 24 to 28 are cases where the second space 20 is visually recognized from the first space 10 .

[0084] like Figure 13 As shown, under the lighting conditions, by making the "current" or "voltage" of the driving light source 32 different according to Examples 1 to 28, the "power" of the driving light source 32 is made different. "Light extraction surface brightness A" and "opposing surface brightness B" represent the results of measuring the brightness A of the light extraction surface 315 and the brightness B of the opposing surface 314 corresponding to the driving power of the light source 32 by the above-mentioned two-dimensional spectroradiometer 200. "First object brightness C" and "second object brightness D" in each example represent the results obtained by measuring the brightness C of the first object M1 and the brightness D of the second object M2 by the above-mentioned brightness meter 300. "A / C" is a calculated value using the measurement results of "light extraction surface brightness A" and "first object brightness C". "B / D" is a calculated value using the measurement results of "opposing surface brightness B" and "second object brightness D".

[0085] Figure 13The "visibility" in the table represents the evaluation result of visibility based on the calculated values ​​of "A / C" and "B / D". The relationship between the calculated value ranges of "A / C" and "B / D" and the symbols "◎" to "×" representing "visibility" is as follows.

[0086] ◎: When the calculated values ​​of "A / C" and "B / D" are 30 or more

[0087] ○: When "A / C" and "B / D" are 10 or more and less than 30

[0088] △: When "A / C" and "B / D" are 5 or more and less than 10

[0089] ×: When "A / C" and "B / D" are less than 5

[0090] It should be noted that Figure 13 The symbols "◎" to "×" in the table simply indicate the range of the calculated values ​​for "A / C" and "B / D" and do not indicate whether visibility is good or bad. "◎", "○", and "△" indicate that objects located in the space opposite the surface lighting device 30 are almost impossible to visually identify from the evaluator's space. "×" indicates that objects located in the space opposite the surface lighting device 30 are visually visible from the evaluator's space.

[0091] Figure 14 is by Figure 13 The measured values ​​of "light extraction surface brightness A" and "opposing surface brightness B" in the horizontal axis are set as the horizontal axis and the Figure 13 The calculated values ​​of "A / C" and "B / D" in the graph are set as the vertical axis, and the results of each example are plotted. Figure 14 The right side of the figure in FIG. 15 shows a captured image corresponding to a view in which the surface lighting device 30 is visually recognized in the lighting space 100 , together with the evaluation result of “visibility” in FIG. 15 .

[0092] like Figure 13-14 As shown, the evaluation results for "visibility" are "◎" in Examples 1 to 7, "○" in Examples 8 to 15, "△" in Examples 16 to 20, and "×" in Examples 21 to 28. Therefore, it can be seen that in Examples 1 to 20, the first space 10 is almost invisible from the second space 20. On the other hand, in Examples 24 to 28, it can be seen that the second space 20 is visible from the first space 10. Therefore, when the conditions of Examples 1 to 20 are used when observing the first space 10 from the second space 20, and the conditions of Examples 24 to 28 are used when observing the second space 20 from the first space 10, it can be seen that the lighting space 100 has anisotropy in visual recognition.

[0093] according to Figure 13-14It can be seen that if (A / C) / (B / D) is greater than 1, the lighting space 100 has visual anisotropy. Furthermore, from the perspective of ensuring that the lighting space 100 has appropriate visual anisotropy, it is more preferable if (A / C) / (B / D) is 2 or greater. Furthermore, from the above perspective, it is further preferable that A / C is 5 or greater. Furthermore, from the above perspective, it is particularly preferable that B / D is 5 or less.

[0094] <Effects of Illuminating Space 100>

[0095] As described above, in this embodiment, it is possible to provide a lighting space 100 having visually recognizable anisotropy and a lighting method using the lighting space 100. It should be noted that the lighting space 100 is not limited to a space in which the first space 10 is barely visible from the second space 20 but the second space 20 is visible from the first space 10, but may also be a space in which the second space 20 is barely visible from the first space 10 but the first space 10 is visible from the second space 20.

[0096] In addition, in this embodiment, Figure 11-12 As shown, the illumination space 100 may also include a variable unit 500 that changes the power supplied to the light source 32 based on the brightness of at least one of the first object M1 and the second object M2. By using the variable unit 500 to vary the power supplied to the light source 32, the amount of light extracted from the surface illumination device 30 can be varied. Thus, even when the brightness of at least one of the first object M1 and the second object M2 varies, the amount of light extracted from the surface illumination device 30 can be varied based on the brightness, thereby enabling the illumination space 100 to have appropriate visual anisotropy.

[0097] For example, if the brightness of the first object M1 is high due to the overall brightness of the first space 10, for example, if the A / C ratio is 5 or greater, the condition is violated, and the first object M1 located in the first space 10 may be visible from the second space 20. In such a case, by increasing the power supplied to the light source 32 using the variable unit 500, the amount of light extracted from the surface lighting device 30 is increased, and the first object M1 located in the first space 10 can be made invisible from the second space 20.

[0098] exist Figure 11-12 The variable unit 500 shown may be a variable resistor, such as a rotary potentiometer that varies power by rotation or a slide potentiometer that varies power by sliding. The variable unit 500 may be operated manually or electrically using a drive unit such as a motor.

[0099] As a variation of the embodiment, the light guide member 31 may have a concave-convex shape on the surface of the light guide plate 311 instead of the air cavity film 312. The concave-convex shape provided on the surface of the light guide plate 311 enables the light guide member 31 to extract the light guided inside the light guide plate 311 to the outside.

[0100] The light guide component 31 may also include other functional layers. For example, the light guide component 31 may include a refractive index-varying layer between the light guide plate 311 and the air cavity film 312. This refractive index-varying layer is used to reduce brightness degradation as the light moves away from the light source 32 and has multiple regions with different refractive indices. For example, a layer may have more low-refractive index regions closer to the light source 32 and more high-refractive index regions farther away from the light source 32. Furthermore, the light guide component 31 may include a surface treatment layer such as a hard coat layer or a low-refractive index layer on the outer side of the air cavity film 312 (opposite to the side where the light guide plate 311 is located).

[0101] As mentioned above, although the preferred embodiment was described in detail, the present invention is not limited to the above embodiment, and various modifications and substitutions can be added to the above embodiment without departing from the scope described in the claims.

[0102] The lighting space of the embodiment has visual anisotropy. The lighting device of the embodiment can provide new applications.

[0103] The embodiments of the present invention are as follows, for example.

[0104] <1> A lighting space comprises a surface lighting device and a first space and a second space divided by the surface lighting device, the surface lighting device comprising a light-guiding component for guiding light incident from a light source and extracting light from a light extraction surface, the second space being illuminated by the light extracted from the light extraction surface, and when the brightness of a first object located in the first space is set to C, the brightness of the light extraction surface is set to A, the brightness of a second object located in the second space is set to D, and the brightness of a surface of the light-guiding component opposite to the light extraction surface is set to B, (A / C) / (B / D) is greater than 1.

[0105] <2> According to the above <1> The lighting space described above, wherein (A / C) / (B / D) is greater than or equal to 2.

[0106] <3> According to the above <1> The lighting space described above has an A / C of 5 or above.

[0107] <4> According to the above <1> ~ <3> The lighting space described in any one of the preceding claims, wherein B / D is 5 or less.

[0108] <5> According to the above <1> ~ <4> The lighting space described in any one of the preceding claims, wherein, when viewed from the side, the surface lighting device illuminates the second space with a light distribution within a polar angle of 90±30 degrees.

[0109] <6> According to the above <1> ~ <5> The lighting space described in any one of the preceding claims, wherein, when viewed from the side, the surface lighting device illuminates the first space with a light distribution having a polar angle smaller than 45 degrees or larger than 135 degrees.

[0110] <7> According to the above <1> ~ <6> The lighting space described in any one of the preceding claims further includes a variable unit configured to change the power supplied to the light source according to the brightness of at least one of the first object and the second object.

[0111] <8> A lighting method, comprising: illuminating a lighting space having a first space and a second space divided by the surface lighting device using a surface lighting device, wherein the surface lighting device guides light incident from a light source through a light-guiding component and extracts the light from a light extraction surface, and illuminates the second space with the light extracted from the light extraction surface; when the brightness of a first object located in the first space is set to C, the brightness of the light extraction surface is set to A, the brightness of a second object located in the second space is set to D, and the brightness of a surface of the light-guiding component opposite to the light extraction surface is set to B, (A / C) / (B / D) is greater than 1.

[0112] This application is based on and claims the benefit of priority from Japanese Patent Application No. 2023-022185 filed with the Japan Patent Office on February 16, 2023, and incorporates the entire contents of that Japanese patent application.

[0113] Description of Reference Numerals

[0114] 1: Ceiling

[0115] 2: Floor

[0116] 10: First Space

[0117] 20: Second Space

[0118] 30: Surface lighting device

[0119] 31: Light guide components

[0120] 310: Main side

[0121] 311: Light guide plate

[0122] 312: Air cavity film

[0123] 313: Light incident surface

[0124] 314: Opposite surface

[0125] 315: Light extraction surface

[0126] 331: Air cavity

[0127] 331a: curved surface

[0128] 331b: Flat surface

[0129] 331c: Edge

[0130] 32: Light Source

[0131] 100: Lighting Space

[0132] 200: Two-dimensional spectroradiometer

[0133] 300: Luminance meter

[0134] 400: Power supply

[0135] 500: variable part

[0136] A~D: Brightness

[0137] L, W, H: Length

[0138] M1: First Object

[0139] M2: Second object

[0140] Px, Py: spacing

[0141] Ri: incident light

[0142] Ro: emerging light

[0143] Ro': reverse outgoing light

[0144] Ro1, Ro1': Arrow

[0145] U:User

Claims

1. A lighting space, characterized in that: have: Surface lighting device; The first space and the second space divided by the surface lighting device, The surface lighting device includes a light guide member that guides light incident from a light source and extracts it from a light extraction surface, and illuminates the second space using the light extracted from the light extraction surface. When the brightness of the first object located in the first space is set to C, the brightness of the light extraction surface is set to A, the brightness of the second object located in the second space is set to D, and the brightness of the surface of the light-guiding component opposite to the light extraction surface is set to B, (A / C) / (B / D) is greater than 1.

2. The lighting space according to claim 1, characterized in that: (A / C) / (B / D) is 2 or more.

3. The lighting space according to claim 1, characterized in that: A / C is 5 or above.

4. The lighting space according to claim 1, characterized in that: B / D is 5 or less.

5. The lighting space according to claim 1, characterized in that: When viewed from the side, the surface lighting device illuminates the second space with a light distribution within a polar angle of 90±30 degrees.

6. The lighting space according to claim 1 or 2, characterized in that: When viewed from the side, the surface lighting device illuminates the first space with a light distribution having a polar angle smaller than 45 degrees or larger than 135 degrees.

7. The lighting space according to claim 1, characterized in that: The device further includes a variable unit configured to change the power supplied to the light source according to the brightness of at least one of the first object and the second object.

8. A lighting method for lighting a lighting space having a first space and a second space divided by the surface lighting device using a surface lighting device, characterized in that: The surface lighting device guides the light incident from the light source through the light guide component and takes it out from the light extraction surface. The second space is illuminated by the light extracted from the light extraction surface, When the brightness of the first object located in the first space is set to C, the brightness of the light extraction surface is set to A, the brightness of the second object located in the second space is set to D, and the brightness of the surface of the light-guiding component opposite to the light extraction surface is set to B, (A / C) / (B / D) is greater than 1.

Images