WO2012144268A1 - Light duct and lighting device - Google Patents

Abstract

A light duct according to an embodiment of the present invention is provided with a duct main body, in which are formed at least one light collecting opening and at least one opening part, and a film having half-mirror surface properties attached to each of the at least one opening parts.

Description

Light duct and lighting device Cross-reference of related applications

This application claims the priority of Japanese Patent Application No. 2011-096358 filed on April 22, 2011.

The present invention relates to an optical duct and a lighting device.

Conventionally, various optical ducts are known. For example, Patent Document 1 below discloses an optical duct device characterized in that the opening area of the light extraction port is increased from the daylighting port to the depth of the optical duct. Patent Document 2 below describes a light guide light extraction mechanism having a predetermined maximum length and a predetermined light emission characteristic. In this extraction mechanism, the short light guide exhibits a substantially uniform surface light intensity due to the short segments removed from the predetermined end of the predetermined maximum length extraction mechanism and incorporated into the short light guide.

JP 2000-149628 A US Pat. No. 5,901,266

In the methods as described in Patent Documents 1 and 2, the light incident from the lighting port is absorbed or leaked while traveling through the duct, and the region near the lighting port and the region away from the lighting port. The difference in illuminance between the two becomes large. Therefore, it is required to efficiently transmit light in the duct and improve the uniformity of the illuminance of the light emitted from the duct to the outside.

An optical duct according to an aspect of the present invention includes a duct body formed with at least one light outlet, at least one opening, and a film having semi-specularity attached to each of the at least one opening. With.

In this case, since the film having semi-specularity is attached to each of the at least one opening, the light incident from the lighting port is not absorbed in the opening or radiated outside the duct more than necessary. Continue on. Thereby, light can be efficiently transmitted to a region away from the lighting port, and as a result, uniformity of illuminance can be enhanced in the entire light duct.

In an optical duct according to another embodiment, a plurality of openings may be formed side by side in the longitudinal direction of the duct body.

In a light duct according to still another embodiment, the reflectance of the film may be 0.70 to 0.90.

In the optical duct according to still another aspect, one side of the film facing the inside of the duct body may be bead-coated.

In the light duct according to another aspect, the first film and the second film each having polarization and semi-specularity are attached to at least the opening closest to the daylighting port, and the second film is The first film may be overlapped with the first film so as to form an angle larger than 0 degree and smaller than 90 degrees.

In the optical duct according to another aspect, the first and second films are attached to two or more continuous openings of the plurality of openings, and any adjacent two or more of the openings are adjacent to each other. For the two openings, the angle formed by the first film and the second film in the opening closer to the daylight opening is equal to or greater than the angle formed by the first film and the second film in the other opening. There may be.

In the optical duct according to still another aspect, the reflectivities of the first and second films may be 0.20 to 0.80, respectively.

In the optical duct according to still another embodiment, one of the first and second films is provided so as to be rotatable with respect to the other, whereby the angle may be adjustable.

In the optical duct according to still another embodiment, the shapes and dimensions of the plurality of openings may be substantially the same.

An illumination device according to an aspect of the present invention includes the above-described optical duct and a light source provided in the optical duct.

In a lighting device according to another embodiment, a light source may be provided inside the duct body.

In a lighting device according to yet another embodiment, the light source may be provided below the surface of the duct body in which the opening is formed.

An illuminating device according to another aspect of the present invention includes an illuminance sensor that measures illuminance, and turns on the light source when the illuminance measured by the illuminance sensor is less than a first threshold, and the illuminance is greater than or equal to the second threshold. In some cases, the circuit may further comprise a circuit for turning off the light source, wherein the second threshold value is larger than the first threshold value.

An illuminating device according to another aspect includes an illuminance sensor that measures illuminance, and when the illuminance measured by the illuminance sensor is less than a first threshold, the luminance of the light source is increased, and the measured illuminance is the second The circuit further includes a circuit for lowering the luminance of the light source when the threshold is equal to or higher than the threshold, wherein the second threshold is larger than the first threshold.

According to one aspect of the present invention, it is possible to efficiently transmit light in a duct and improve the uniformity of the illuminance of light emitted from the duct to the outside.

It is a perspective view which shows the example of the optical duct which concerns on 1st and 2nd embodiment. It is a bottom view of the optical duct shown in FIG. (A)-(d) is the III-III sectional view taken on the line of the optical duct based on 1st Embodiment. (A)-(c) is the III-III sectional view taken on the line of the optical duct based on 2nd Embodiment. It is a figure which shows the positional relationship of the two semi-specular films which concern on 2nd Embodiment. It is a perspective view which shows the example of the optical duct which concerns on 3rd Embodiment, and the illuminating device which concerns on 4th Embodiment. It is a front view of the optical duct shown in FIG. It is a rear view of the optical duct shown in FIG. It is a top view of the optical duct shown in FIG. It is a bottom view of the optical duct shown in FIG. It is a right view of the optical duct shown in FIG. It is a left view of the optical duct shown in FIG. FIG. 13 is a cross-sectional view taken along the line XIII-XIII of FIG. 10, showing an example of a lighting apparatus according to a fourth embodiment. FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 10, illustrating an example of a lighting device according to a fourth embodiment. FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG. 10, showing another example of the illumination device according to the fourth embodiment. FIG. 14 is a cross-sectional view taken along the line XIV-XIV in FIG. 10, showing another example of the illumination device according to the fourth embodiment. FIG. 13 is a cross-sectional view taken along line XIII-XIII in FIG. 10, showing still another example of the illumination device according to the fourth embodiment. FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 10, showing still another example of the illumination device according to the fourth embodiment. It is a bottom view which shows another example of the illuminating device which concerns on 4th Embodiment. FIG. 20 is a sectional view taken along line XX-XX in FIG. FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 10, showing still another example of the illumination device according to the fourth embodiment. It is a bottom view which shows another example of the illuminating device which concerns on 4th Embodiment. FIG. 23 is a sectional view taken along line XXIII-XXIII in FIG. FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. 10, showing still another example of the illumination device according to the fourth embodiment. It is a bottom view which shows another example of the illuminating device which concerns on 4th Embodiment. It is a figure which shows the outline | summary of a structure of the optical duct in the comparison 1 of an Example. It is a figure which shows the outline | summary of a structure of the optical duct in the comparison 2 and 3 of an Example. It is a graph which shows the result of the comparison 2. 10 is a graph showing the result of comparison 3. It is a figure which shows the outline | summary of a structure of the illuminating device in the comparison 4 of an Example. It is a graph which shows the result of the comparison 4. It is a perspective view which shows the modification of the shape of an optical duct or an illuminating device. It is a perspective view which shows the modification of the shape of an optical duct or an illuminating device. It is a figure which shows the example of introduction of an optical duct.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description of the drawings, the same or equivalent elements are denoted by the same reference numerals, and redundant description is omitted.

(First embodiment)
First, the configuration of the optical duct 10 according to the first embodiment will be described with reference to FIGS. The light duct 10 is a tubular member for transporting taken light to a target position and radiating it to a space outside the duct, thereby using the light as illumination or auxiliary illumination. The optical duct 10 is employed, for example, to use sunlight for indoor lighting. But the light conveyed by the optical duct 10 is not limited to natural light (sunlight), and may be artificial light.

An example of the optical duct 10 is shown in FIG. The cross-sectional shape of the main body (hereinafter referred to as “duct main body”) 11 of the optical duct 10 in FIG. 1 is rectangular. At one end of the duct body 11, a lighting port 12 for taking in the light L is formed. On the entire inner wall of the duct body 11, a reflective material that almost totally reflects light is attached by laminating or the like. As shown in FIGS. 1 and 2, a plurality of windows 13 for radiating light to a space outside the duct body 11 are provided at a predetermined interval along the longitudinal direction on one surface extending in the longitudinal direction of the duct body 11. Is formed.

The window 13 includes an opening 14 formed in the duct body 11 and a component (optical layer) that covers the opening 14. The shape and size of each opening 14 are the same or substantially the same. Several configurations of the optical layer are conceivable as shown in FIG.

In the example of FIG. 3A, a film having semi-specularity (hereinafter referred to as “semi-specular film”) 21 is attached to the opening 14 as an optical layer. A film having a semi-specularity is a film having a characteristic of reflecting a part of incident light and transmitting the remaining light with little loss of light due to absorption or the like. Therefore, in the semi-specular film, the relationship “(reflected light) + (transmitted light) ≈ (incident light)” is established.

In this embodiment, the hemispherical reflectance of the semi-specular film 21 is 0.70 to 0.90. Here, the hemispherical reflectance is the ratio of the total luminous flux of reflected light to the total luminous flux of incident light from all directions on the film surface. The light taken into the inside of the duct body 11, that is, into the cavity is normally incident on the surface in the cavity from all directions (all angles), so that the characteristics of the semi-specular film 21 used in the optical duct 10 are hemispherical. It is convenient to characterize by reflectance. This is because the hemispherical reflectance is not affected by the variation in reflectance with the incident angle, and the variation is already taken into account.

This semi-specular film 21 has, for example, a coextruded polymer microlayer (multilayer structure) oriented under appropriate conditions to produce the desired refractive index relationship and the desired reflectivity characteristics. In the production of the semi-specular film 21, the number of micro layers, the layer thickness characteristics, the refractive index, and the like are appropriately selected so as to obtain a desired hemispherical reflectance. From this point, it can be said that the semi-specular film 21 is a film in which the hemispherical reflectance and the hemispherical transmittance are controlled. However, the sum of the hemispherical reflectance and the hemispherical transmittance is approximately 1. Here, the hemispherical transmittance is the ratio of the total luminous flux of transmitted light to the total luminous flux of incident light from all directions on the film surface. The semi-specular film 21 may be a polarizing film or may not be a polarizing film. The semi-specular film 21 may have asymmetric reflection characteristics or may have a multilayer structure having symmetry.

The structure and characteristics of such a semi-specular film 21 are also described in JP-T-2010-528430.

In the example of FIG. 3B, a semi-specular film 21 (multilayer optical film 31) having a polarizing property and having a bead coating 22 on one surface is attached to the opening 14 as an optical layer. The multilayer optical film 31 is attached to the opening 14 so that the bead coating 22 faces the inside of the duct body 11. The bead coating 22 is formed of a known binder resin-made fine beads (for example, polymethyl methacrylate (PMMA) beads) or a polymer binder containing a large number of fine particles such as glass beads. The bead coating 22 is used for diffusing light reflected in the space in the duct body 11.

In the example of FIG. 3C, a semi-specular film 21 (multilayer optical film 32) having a bead coating 22 on one side and a transparent resin diffusion sheet 23 attached to the other side is opened as an optical layer. It is attached to the part 14. This multilayer optical film 32 is also attached to the opening 14 so that the bead coating 22 faces the inside of the duct body 11. Examples of the transparent resin used for the diffusion sheet 23 include polycarbonate, but the material of the diffusion sheet 23 is not limited to this.

In the example of FIG. 3D, the optical layer includes a multilayer optical film 32 and a diffusion plate 42 made of a transparent resin. Specifically, one end of a tubular member 41 having the same cross-sectional shape as the multilayer optical film 32 and laminated with a reflective material on the inside is attached to the duct body 11 so as to cover the multilayer optical film 32. A diffusion plate 42 is attached to the other end of the tubular member 41. Accordingly, a space is formed between the multilayer optical film 32 and the diffusion plate 42. Examples of the transparent resin used for the diffusion plate 42 include acrylic, but the material of the diffusion plate 42 is not limited to this. The diffusion plate 42 may be colored or translucent.

As described above, according to the present embodiment, since the semi-specular film 21 is attached to each opening 14, the light incident from the lighting port 12 is absorbed in the opening 14 or more than necessary. It proceeds through the duct body 11 without being radiated to the outside. Thereby, light can be efficiently transmitted to a region away from the lighting port 12, and as a result, the illuminance uniformity can be enhanced in the entire optical duct 10.

Moreover, according to this embodiment, since the shape and dimension of each opening part 14 can be made the same, the optical duct 10 can be designed and manufactured easily. Furthermore, since the same semi-specular film 21 should just be attached to each opening part 14, manufacture of the optical duct 10 is easy.

(Second Embodiment)
Next, the optical duct 10 according to the second embodiment will be described. The second embodiment differs from the first embodiment in the configuration of the optical layer that forms part of the window 13. Since other configurations in the present embodiment are the same as those in the first embodiment, the description thereof will be omitted, and the configuration of the optical layer will be described below with reference to FIGS.

In the example of FIG. 4A, the first semi-specular film 51 and the second semi-specular film 52 (hereinafter also referred to as “two-layer film 50”) overlapped with each other are used as the optical layer. 14 is attached. In the present embodiment, both the first and second semi-specular films 51 and 52 have polarization. In this embodiment, the lower limit of the hemispherical reflectance of the first and second semi-specular films 51 and 52 may be 0.20, 0.40, or 0.45. The upper limit of the hemispherical reflectance may be 0.55, 0.60, or 0.80. The hemispherical reflectivities of the semi-specular films 51 and 52 may be the same or different. As shown in FIG. 5, the semi-specular films 51 and 52 are overlapped so that one film forms an angle θ that is greater than 0 degree and less than 90 degrees with respect to the other film.

In the example of FIG. 4B, a two-layered film 50 having a transparent resin diffusion plate 61 attached on one side is attached to the opening 14 as an optical layer. In this case, the two-layered film 50 is attached to the opening 14 so that the surface on which the diffusion plate 61 is not attached faces the inside of the duct body 11. Examples of the transparent resin used for the diffusion plate 61 include acrylic, but the material of the diffusion plate 61 is not limited to this. Further, the diffusion plate 61 may be colored or translucent.

The example of FIG. 4C is the same as the example of FIG. 4B in that the optical layer includes a double-layered film 50 and a diffusion plate 61, but the positional relationship between the film 50 and the diffusion plate 61 is different. . Specifically, one end of a tubular member 62 having the same cross-sectional shape as the double-layered film 50 and laminated with a reflective material on the inside is attached to the duct body 11 so as to cover the film 50. A diffusion plate 61 is attached to the other end of the tubular member 62. Therefore, a space is formed between the two stacked films 50 and the diffusion plate 61.

When the optical duct 10 is installed, at least one of the first and second semi-specular films 51 and 52 shown in FIGS. 4 and 5 can rotate around the center point of the opening 14. This means that one semi-specular film is provided to be rotatable with respect to the other. Thus, by making the semi-specular film rotatable, the angle θ can be adjusted when the optical duct 10 is installed. This angle θ may be adjustable after installation.

The two-layered film 50 shown in FIG. 4 only needs to be provided at least in the opening 14 closest to the daylighting port, and in the other opening 14, only one semi-specular film having polarization is used. May be. When two sheets of film 50 are attached to two or more continuous openings 14, the first and second half portions of each window 13 become smaller so that the angle θ in FIG. 5 gradually decreases with distance from the lighting port 12. The positional relationship between the specular films 51 and 52 is adjusted. That is, for any two adjacent openings 14 among two or more consecutive openings 14, the angle θ at the opening 14 closer to the lighting port 12 is the other (the farther from the lighting port 12) opening. 14 or more.

Alternatively, depending on the situation of the end of the light duct 10 on the side opposite to the lighting port 12, for example, when a reflective material is provided on the end on the side opposite to the lighting port 12, the angle θ is from the lighting port 12. You may adjust so that it may become small gradually as it goes away, and also it may adjust so that it may become large as it approaches the edge part which leaves | separates from the lighting port 12 further. By adjusting in this way, the illuminance in the vicinity of the end opposite to the daylighting port 12 can be made more uniform.

Also according to the present embodiment described above, the same effects as those of the first embodiment can be obtained. That is, since the two-layered film 50 each having semi-specularity is attached to at least one opening 14, the light incident from the lighting port 12 is absorbed in the opening 14 or more than necessary outside the duct body 11. The inside of the duct body 11 is advanced without being radiated. Thereby, light can be efficiently transmitted to a region away from the lighting port 12, and as a result, the illuminance uniformity can be enhanced in the entire optical duct 10.

Moreover, according to this embodiment, since the shape and dimension of each opening part 14 can be made the same, the optical duct 10 can be designed and manufactured easily. Moreover, in this embodiment, the uniformity of the illumination intensity in the whole optical duct 10 can be finely adjusted by changing the angle which the two semi-specular films 51 and 52 comprise in each opening part 14. FIG.

In the present embodiment, at least one of the first and second semi-specular films 51 and 52 is rotatable when the optical duct 10 is installed, but the positional relationship between these two semi-specular films is fixed. It may be. An optical duct similar to that of the present embodiment can be created even when several types of two-layered films are prepared in which the angle adjustment between the two semi-specular films is completed and the angle cannot be changed. For example, it is conceivable to prepare in advance a plurality of types of two-layered films having different angles θ shown in FIG. 5 by 5 degrees or 10 degrees.

(Third embodiment)
Next, the configuration of the optical duct 100 according to the third embodiment will be described with reference to FIGS. The optical duct 100 is provided with a single window (opening) extending along the longitudinal direction of the duct body, instead of a plurality of windows (openings), and thus the optical duct 10 in the first and second embodiments. And different. In the following, the description of the same points as in the first and second embodiments will be omitted or briefly described.

An example of the optical duct 100 in the present embodiment is shown in FIGS. FIG. 6 is a perspective view of the optical duct 100, and FIGS. 7 to 12 are six views thereof. The main body (duct main body 111) of the optical duct 100 is substantially L-shaped, and its cross-sectional shape is rectangular. At one end of the duct body 111, a daylighting port 112 for taking in light is formed. The other end of the duct body 111 is closed. A reflective material is attached to the entire inner wall of the duct body 111.

As shown in FIGS. 6 and 10, one window 113 extending along the longitudinal direction of the main body 111 is formed on the bottom surface of the duct main body 111 facing the indoor space. The window 113 is formed by attaching an optical layer to an opening formed in the duct body 111. The specific configuration of the optical layer is the same as that of the first embodiment, and therefore various modifications as shown in FIG. 3 are possible.

Also in this embodiment, since a semi-specular film is used for the window 113, light incident from the lighting port 112 is absorbed by the window 113, or outside the duct body 111 more than necessary at a specific portion of the window 113. It proceeds through the duct body 111 without being radiated. Thereby, light can be efficiently transmitted to a region away from the lighting port 112, and as a result, uniformity of illuminance can be enhanced in the entire light duct 100.

(Fourth embodiment)
Next, the configuration of the illumination device according to the fourth embodiment will be described with reference to FIGS. The lighting device is a device in which artificial lighting is attached to the light duct 100 of the third embodiment that takes in and emits natural light. Artificial lighting is a light source for supplementing brightness. When the artificial illumination is provided inside the light duct, it is possible to improve the uniformity of the illuminance of the light radiated to the outside in the same manner as natural light. In FIGS. 13, 15, and 17, natural light is indicated by reference numeral NL.

The shape and mounting position of artificial lighting are not limited to one. Some examples will be described with reference to FIGS. Each of FIGS. 13 to 25 shows a state in which the lighting device is attached so that the optical duct 100 is embedded in the ceiling C. The kind of light source itself is not limited. For example, the light source may be a light emitting diode (LED), a fluorescent lamp, or an incandescent lamp.

In the lighting device 200A shown in FIGS. 13 and 14, a plurality of trough-type artificial lights (hereinafter referred to as “trough-type lights”) 210 are arranged in a line along the longitudinal direction of the window 113. It is attached to the top surface. The attachment range of the trough illumination 210 in the longitudinal direction of the duct body 111 is substantially the same as the longitudinal dimension of the window 113.

In the lighting device 200B shown in FIGS. 15 and 16, a plurality of bar-type artificial lights (hereinafter referred to as “bar-type lights”) 220 are arranged in a line along the longitudinal direction of the window 113. It is attached to the top surface. The bar-type illumination 220 has a plurality of LEDs 221, and these LEDs 221 are also arranged in a line along the longitudinal direction of the window 113. The attachment range of the bar-type illumination 220 in the longitudinal direction of the duct body 111 is substantially the same as the longitudinal dimension of the window 113.

In the lighting device 200C shown in FIG. 17, a plurality of downlights 230 are attached to the upper surface inside the duct body 111 so as to be aligned in a line along the longitudinal direction of the window 113. The interval between the downlights 230 may be arbitrarily determined. For example, the interval may be set so that the light from the downlight 230 reaches the entire window 113 directly.

18, a plurality of trough-type illuminations 210 are attached to one side surface inside the duct main body 111 so as to be arranged in a line along the longitudinal direction of the window 113. The illumination device 200D can be considered as a modification of the illumination device 200A, and the only difference from the illumination device 200A is the attachment position of the trough illumination 210.

In the lighting device 200E shown in FIGS. 19 and 20, a plurality of trough-type lights 210 are attached to the bottom surface of the duct body 111 (the surface on which the window 113 is formed) so as to be aligned in a line along the longitudinal direction of the window 113. It has been. The trough illumination 210 is supported by a wire 240 extending from above the duct body 111 and exposed to the indoor space.

In the illumination device 200F shown in FIG. 21, a plurality of bar-type illuminations 220 are provided at positions close to the inside of the window 113 so as to be arranged in a line along the longitudinal direction of the window 113. In order to attach the bar-shaped illumination 220, a fixture 250 extending along the longitudinal direction of the window 113 and having a U-shaped cross section is used. The fixture 250 is attached to the inside of the window 113 after being hung by a wire 240 extending from above the duct body 111 so that the opening thereof faces downward. The bar-type illumination 220 is attached to the inner surface of the fixture 250 so that the optical axis of the LED 221 is substantially parallel to the window 113. In order to prevent the light of the bar-type illumination 220 from diffusing into the duct body 111, the interior of the fixture 250 to which the bar-type illumination 220 is attached is isolated from the space within the duct body 111 through which natural light passes. A reflective material is affixed to the inner wall of the fixture 250.

The illumination device 200G shown in FIGS. 22 and 23 is a modification of the illumination device 200E shown in FIGS. The trough illumination 210 is attached to the outside of the duct body 111 in the same manner as the illumination device 200E, but the attachment location is different from the illumination device 200E. In the lighting device 200E, the trough-type illumination 210 is attached to the approximate center in the width direction of the window 113, whereas in the lighting device 200G, the trough-type illumination 210 is attached near one end portion in the width direction. The trough illumination 210 is attached to the bottom surface of the duct body 111 by a fixture 251 extending from the ceiling C to the window 113.

A lighting device 200H shown in FIG. 24 is a modification of the lighting device 200F shown in FIG. The illumination device 200H differs from the illumination device 200F in that the wire 240 is omitted and the bar-type illumination 220 is attached only by the fixture 252. Also in this lighting device 200H, the inside of the fixture 252 to which the bar-type lighting 220 is attached is isolated from the space in the duct body 111 through which natural light passes. A reflective material is affixed to the inner wall separating the interior.

As described above, the configuration of the lighting device according to the present embodiment is various, but it is needless to say that the specific structure is not limited to the above.

An illuminance sensor for automatically dimming, turning on or off the light source may be attached to any of the above lighting devices. For example, as shown in FIG. 25, the illuminating device 200A shown in FIGS. 13 and 14 may be attached to the ceiling C, and the illuminance sensor 300 for measuring the illuminance in the indoor space may be attached to the ceiling C.

In the example of FIG. 25, each illuminance sensor 300 is electrically connected to each trough illumination 210 by a wiring 310. Each trough illumination 210 includes a circuit (not shown) for dimming, turning on or off according to the illuminance measured by the corresponding illuminance sensor 300. This circuit turns on the trough illumination 210 or increases its luminance when the measured illuminance becomes less than the first threshold Th1, and the illuminance exceeds the second threshold Th2 (where Th2> Th1). This is a circuit for turning off the trough-type illumination 210 or lowering its luminance when it becomes.

As described above, since the same optical duct as that of the third embodiment is used in this embodiment, the same effect as that of the third embodiment can be obtained. That is, the natural light incident from the lighting port 112 travels through the duct body 111 without being absorbed by the window 113 or being radiated outside the duct body 111 more than necessary at a specific portion of the window 113. As a result, natural light can be efficiently transmitted to a region away from the lighting port 112, and as a result, the uniformity of the illuminance of natural light can be enhanced throughout the light duct 100.

Further, in the present embodiment, since the light duct 100 is provided with artificial illumination, when the brightness is insufficient with only natural light, the artificial illumination is dimmed or lit, so that the necessary brightness in an arbitrary time zone is obtained. You can get it. When the illuminance sensor 300 and the circuit are provided, the artificial illumination can be automatically dimmed, turned on, or turned off according to the intensity of natural light, so that the convenience of the lighting device is further improved.

Hereinafter, examples relating to the optical duct will be described, but the configuration of the optical duct is not limited to the following examples. The optical ducts in Examples 1-1 and 1-2 correspond to those shown in the first embodiment, and the optical ducts in Examples 2-1 and 3-1 correspond to those shown in the second embodiment. The illumination device in Example 4-1 corresponds to that shown in the fourth embodiment.

Example 1-1
A duct body was manufactured using a 5 mm-thick polystyrene plate material on which a mirror film (DF2000MA manufactured by 3M) was laminated. The duct body had a cross-sectional shape of 200 mm × 200 mm square and a length of 3000 mm. Three windows of 150 mm × 150 mm were formed on one side of the duct body. Regarding the both ends of the optical duct, the distance from one end to the window closest to the end was 425 mm. The distance between adjacent windows was 850 mm. Below, each window is shown as window 1, window 2, and window 3 in order from the one close to the light source. The end of the light duct closer to the window 3 was closed by the plate material. An outline of the structure of such a duct body is shown in FIG.

Each window was provided with an optical layer as shown in FIG. As the multilayer optical film 32, a multilayer optical film manufactured by 3M Co., which includes a semi-specular film having a hemispherical reflectance of about 0.75 and having polarizing properties, was used. Acrylite (registered trademark) EX432 (milky white) manufactured by Mitsubishi Rayon Co., Ltd. was used for the diffusion plate. The distance between the opening and the diffusion plate was 50 mm.

Example 1-2
In the same manner as in Example 1-1, a duct body was produced and windows 1 to 3 were formed. The difference from Example 1-1 is that an additional diffusion plate (EX432) is attached to the diffusion sheet side of the multilayer optical film manufactured by 3M in the window 1. Therefore, the window 1 uses two diffusion plates. The optical layers in the windows 2 and 3 were the same as those in Example 1-1.

(Comparative Example 1-1)
In the same manner as in Example 1-1, a duct body was produced and windows 1 to 3 were formed. The difference from Example 1-1 is that a perforated mirror film (ESR manufactured by 3M) in which small holes are regularly arranged in two dimensions is used instead of the multilayer optical film. The aperture ratio of the perforated mirror film was 50%, 70%, and 80% in windows 1 to 3, respectively.

(Comparative Example 1-2)
In the same manner as in Example 1-1, a duct body was produced and windows 1 to 3 were formed. The difference from Example 1-1 is that the multilayer optical film was not attached. Therefore, the opening is covered only by the diffusion plate 50 mm away from the opening.

(Comparison of illuminance in each window (Comparison 1))
A light source (110 V / 40 W incandescent bulb (manufactured by Asahi Denki Co., Ltd.)) was used under the same conditions for each of the optical ducts produced in Examples 1-1 and 1-2 and Comparative Examples 1-1 and 1-2. installed. Specifically, the light source was installed at one end of the optical duct close to the window 1 so that the optical axis forms an angle of 45 degrees with the surface on which the three windows are formed. For each light duct, 10 minutes after the light source was turned on, the illuminance on the surface of each diffusion plate was measured with an illuminometer (CL-200 manufactured by Konica Minolta). Three measurement points of illuminance were provided on the surface of each diffusion plate. As for the window 1, the center of the diffuser is defined as a measuring point 1-2, and a point advanced 60 mm from the center toward the light source along the longitudinal direction of the optical duct is defined as a measuring point 1-1. A point advanced 60 mm in the opposite direction along the center was defined as a measurement point 1-3. Similarly, the measurement points 2-1 to 2-3 and 3-1 to 3-3 were provided for the windows 2 and 3. In FIG. 26, each measurement point is indicated by a cross.

The illuminance at each measurement point for each of the optical ducts of Examples 1-1 and 1-2 and Comparative Examples 1-1 and 1-2 is shown in Table 1 below.

For the light ducts of Examples 1-1 and 1-2 and Comparative Examples 1-1 and 1-2, the average illuminance and standard deviation at each window, and the average values of the average illuminance and standard deviation, respectively. It is shown in Table 2 below.

Example 2-1
A duct body was manufactured using a 5 mm thick polystyrene plate material on which a mirror film (ESR manufactured by 3M) was laminated. The duct body had a cross-sectional shape of 200 mm × 200 mm square and a length of 3300 mm. Six windows of 100 mm × 100 mm were formed on one side of the duct body. Regarding the both ends of the optical duct, the distance from one end to the window closest to the end was 225 mm. The distance between adjacent windows was 450 mm. Below, each window is shown as window 1, window 2,..., Window 6 in order from the side closer to the light source. The end of the light duct closer to the window 6 was opened. An outline of the structure of such a duct body is shown in FIG.

The optical layers as shown in FIG. 4B were attached to the windows 1 to 5. As the first and second semi-specular films, DBEF manufactured by 3M having a reflectivity of about 0.50 and having a polarizing property was used. Acrylite (registered trademark) EX432 (white) manufactured by Mitsubishi Rayon Co., Ltd. was used as the diffusion plate. In windows 1 to 5, the angles formed by the two semi-specular films were 70 degrees, 60 degrees, 50 degrees, 50 degrees, and 35 degrees, respectively. On the other hand, an optical layer formed by attaching one white diffuser plate (EX432) to one semi-specular film (DBEF) was attached to the window 6.

(Comparative Example 2-1)
In the same manner as in Example 2-1, a duct body was produced and windows 1 to 6 were formed. The difference from Example 2-1 is that an optical layer consisting of one polarizing half-specular film (DBEF) and one white diffusion plate (EX432) is attached to all windows. is there. This means that the optical layer in the window 6 in Example 2-1 was applied to all windows.

(Comparative Example 2-2)
In the same manner as in Example 2-1, a duct body was produced and windows 1 to 6 were formed. The difference from Example 2-1 is that an optical layer composed of only one white diffusion plate (EX432) is attached to all windows.

(Comparison of illuminance in each window (Comparison 2))
A light source (110 V / 40 W incandescent bulb (manufactured by Asahi Denki)) was installed under the same conditions for each of the optical ducts produced in Example 2-1 and Comparative Examples 2-1 and 2-2. Specifically, a light source was installed at one end of the optical duct close to the window 1 so that the optical axis coincided with the longitudinal direction of the optical duct. Then, 10 minutes after turning on the light source, the illuminance at the center of the surface of each diffusion plate was measured with an illuminometer (CL-200 manufactured by Konica Minolta). The measurement results are shown in Table 3 below and FIG.

Example 3-1
In the same manner as in Example 2-1, a duct body was produced and windows 1 to 6 were formed. The angles formed by two semi-specular films (two DBEFs each having a reflectance of about 0.50) in windows 1 to 5 are 70 degrees, 50 degrees, 45 degrees, 45 degrees, and 20 degrees, respectively. It was. The configuration of the window 6 was the same as in Example 2-1.

(Comparative Example 3-1)
In the same manner as in Example 3-1, a duct body was produced and windows 1 to 6 were formed. The difference from Example 3-1 is that a perforated mirror film (ESR manufactured by 3M) in which small holes are regularly arranged in two dimensions is used instead of the semi-specular film. The aperture ratio of the perforated mirror film was 30%, 50%, 70%, 80%, and 90% in windows 1 to 5, respectively. In the window 6, only a white diffuser plate (EX432) was attached without using a perforated mirror film.

(Comparative Example 3-2)
The same optical duct as in Comparative Example 2-2 was used.

(Comparison of illuminance in each window (Comparison 3))
For each optical duct manufactured in Example 3-1 and Comparative Examples 3-1 and 3-2, a light source was installed and turned on in the same manner as in Comparative Example 2, and 10 minutes after the light source was turned on. The illuminance at the center of the surface of each diffusion plate was measured with an illuminometer (CL-200 manufactured by Konica Minolta). The measurement results are shown in Table 4 below and FIG.

Example 4-1
A lighting device as shown in FIG. 30 was produced. Specifically, an L-shaped duct body was prepared using a 5 mm-thick polystyrene plate material on which a mirror film (DF2000MA manufactured by 3M) was laminated. The cross-sectional shape of the duct body was a rectangle with a width of 65 mm and a height of 45 mm, and the total extension was 815 mm. The length from the lighting port formed at one end to the corner (the length of the vertical portion) was 255 mm, and the length from the corner to the other end (the length in the horizontal direction) was 560 mm. The other end was closed by the plate material.

A 500 mm × 55 mm window was formed on the bottom surface of the horizontal portion of the duct body. The window was provided with an optical layer as shown in FIG. As the optical layer, a multilayer optical film manufactured by 3M Co., which includes a semi-specular film having a hemispherical reflectance of about 0.75 (thus, a hemispherical transmittance of about 0.25) and a polarizing property was used.

二 つ Two bar-type lights were installed as artificial lights on one inner surface of the horizontal part of the duct body. This bar-type illumination is an illumination device in which 12 LEDs (NS6W083B manufactured by Nichia Corporation, 110V / 12W) are arranged in a line. Therefore, this artificial illumination has a total of 24 LEDs. The distance between the LEDs was 20 mm.

(Comparative Example 4-1)
In the same manner as in Example 4-1, a duct body was produced, a window was formed, and artificial lighting was attached. The difference from Example 4-1 is that a light diffusing film (3635-30 manufactured by 3M) having a transmittance of about 30% was used instead of the multilayer optical film.

(Comparative Example 4-2)
In the same manner as in Example 4-1, a duct body was produced, a window was formed, and artificial lighting was attached. A difference from Example 4-1 is that an acrylic sheet (422L manufactured by Kuraray Co., Ltd.) having a transmittance of about 87% was used instead of the multilayer optical film.

(Comparative Example 4-3)
In the same manner as in Example 4-1, a duct body was produced, a window was formed, and artificial lighting was attached. The difference from Example 4-1 is that an acrylic sheet (E032 manufactured by Sumitomo Chemical Co., Ltd.) having a transmittance of about 55% was used instead of the multilayer optical film.

(Comparison of illuminance in windows (Comparison 4))
A 110 V / 35 W halogen lamp (manufactured by Ushio Lighting Co., Ltd.) was installed as a light source simulating natural light in each of the lighting devices manufactured in Example 4-1 and Comparative Examples 4-1 to 4-3. Specifically, the halogen lamp was installed in the lighting port so that the optical axis forms an angle of 45 degrees with one side surface of the optical duct. For each lighting device, the illuminance on the window surface was measured with an illuminometer (CL-200 manufactured by Konica Minolta) 10 minutes after the light source was turned on. Five measurement points of illuminance were provided on the surface of the window. Specifically, a measurement point A is provided at a location 35 mm away from the end of the window closer to the lighting port, and measurement points B to E are provided every time 110 mm travels from the measurement point A. Each of the measurement points A to E is located substantially at the center in the width direction of the window. In FIG. 30, each measurement point is indicated by a circle.

First, the illuminance at each measurement point when only the halogen lamp is turned on (when only natural light is used) is shown in Table 5 and FIG. Table 5 shows the average and standard deviation of illuminance at five points.

Next, the illuminance at each measurement point and its average and standard deviation when all of the halogen lamp and bar-type lighting are turned on (assuming that artificial light is used as an auxiliary to natural light) are as follows: Table 6 shows.

The embodiments and examples of the present invention have been described in detail above. However, the present invention is not limited to the above-described embodiments and examples. The present invention can be variously modified without departing from the gist thereof.

The shape and dimensions of the optical duct are not limited to the above embodiment and examples. For example, the duct body does not have to be linear along its longitudinal direction, and may be bent entirely or partially. Moreover, the duct main body may branch on the way. Furthermore, the cross-sectional shape of the duct body may be other than a rectangle (for example, a circle).

The position and shape of the window (opening) are also arbitrary. For example, you may form the window of shapes other than a rectangle (for example, circle) in arbitrary positions. When providing a plurality of windows, the interval between two adjacent windows may not be the same. The windows do not need to be arranged accurately in a line, and the positions of the windows in the width direction of the duct body may be different from each other. Two or more windows may be arranged in the longitudinal direction of the duct body.

The position of the lighting port does not need to be one end in the longitudinal direction of the duct body, and the lighting port may be formed at an arbitrary point in the longitudinal direction. Moreover, the number of the lighting openings may be plural.

Therefore, the optical duct can be designed according to the installation location. The T-shaped light duct or lighting device 400 composed of two adjacent L-shaped light ducts shown in FIG. 32 or the linear light duct or lighting device 410 shown in FIG. 33 is the third or fourth embodiment. It is a variation of the form. The optical duct 10 shown in FIG. 34 is a modification of the first or second embodiment, and the optical duct 10 is disposed in the building B in order to take sunlight L into the room.

A lighting device including an optical duct in which a plurality of windows are formed (for example, the optical duct 10 according to the first and second embodiments) and the various artificial lights in the fourth embodiment is also within the scope of the present invention. is there.

DESCRIPTION OF SYMBOLS 10 ... Light duct, 11 ... Duct body, 12 ... Daylighting port, 13 ... Window, 14 ... Opening part, 21 ... Semi-specular film, 22 ... Bead coating, 23 ... Diffusion sheet, 31, 32 ... Multilayer optical film, 41 DESCRIPTION OF SYMBOLS ... Tubular member, 42 ... Diffuser plate, 50 ... Two-layer film, 51 ... First semi-specular film, 52 ... Second semi-specular film, 61 ... Diffuser plate, 62 ... Tubular member, 100 ... Light Duct, 111 ... Duct body, 112 ... Daylight opening, 113 ... Window, 200A to 200H ... Illumination device, 210 ... Trough illumination (light source), 220 ... Bar illumination (light source), 230 ... Downlight (light source), 300 ... illuminance sensors, 400 and 410 ... light ducts or lighting devices.

Claims (14)

1. A duct body formed with at least one daylight opening and at least one opening;
   An optical duct comprising: a film having semi-specularity attached to each of the at least one opening.
2. A plurality of the openings are formed side by side in the longitudinal direction of the duct body.
   The optical duct according to claim 1.
3. The hemispherical reflectance of the film is 0.70-0.90,
   The optical duct according to claim 1 or 2.
4. One side of the film facing the inside of the duct body is bead coated,
   The optical duct according to claim 3.
5. A first film and a second film, each having polarization and semi-specularity, are attached to at least the opening closest to the daylighting port,
   The second film is overlaid on the first film so as to form an angle of greater than 0 degrees and less than 90 degrees with respect to the first film;
   The optical duct according to claim 2.
6. The first and second films are attached to two or more continuous openings of the plurality of openings,
   For any two adjacent openings of the two or more continuous openings, the angle formed by the first film and the second film in the opening closer to the daylighting opening is the other opening. Is an angle formed by the first film and the second film in the portion,
   The optical duct according to claim 5.
7. The hemispherical reflectances of the first and second films are 0.20 to 0.80, respectively.
   The optical duct according to claim 5 or 6.
8. One of the first and second films is provided to be rotatable with respect to the other, whereby the angle can be adjusted.
   The optical duct according to any one of claims 5 to 7.
9. The shapes and dimensions of the plurality of openings are substantially the same,
   The optical duct according to any one of claims 5 to 8.
10. An optical duct according to any one of claims 1 to 9,
    A lighting device comprising a light source provided in the light duct.
11. The light source is provided inside the duct body;
    The lighting device according to claim 10.
12. The light source is provided below the surface of the duct body in which the opening is formed.
    The lighting device according to claim 10.
13. An illuminance sensor for measuring illuminance;
    A circuit that turns on the light source when the illuminance measured by the illuminance sensor is less than a first threshold, and turns off the light source when the illuminance is greater than or equal to a second threshold; The lighting device according to any one of claims 10 to 12, further comprising the circuit having a threshold value greater than the first threshold value.
14. An illuminance sensor for measuring illuminance;
    A circuit that increases the luminance of the light source when the illuminance measured by the illuminance sensor is less than a first threshold, and decreases the luminance of the light source when the measured illuminance is greater than or equal to a second threshold. The lighting device according to any one of claims 10 to 12, further comprising the circuit in which the second threshold value is larger than the first threshold value.

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