WO2013140695A1

WO2013140695A1 - Illumination device

Info

Publication number: WO2013140695A1
Application number: PCT/JP2012/083680
Authority: WO
Inventors: 高橋　健; 横田　昌広; 修介森田; 修小野; 信雄川村; 大川　猛; 英男太田; 松田　秀三; 西村　孝司
Original assignee: 株式会社東芝
Priority date: 2012-03-23
Filing date: 2012-12-26
Publication date: 2013-09-26
Also published as: JP5531302B2; JP2013201017A

Abstract

This illumination device is provided with: a plurality of discretely arranged light sources (4); a light-permeable cover (5) covering the light sources; and an optical control film (6), which has a plurality of openings (7) provided at a distance from each other, and which is provided to the cover.

Description

Lighting device

Embodiment of this invention is related with the illuminating device which used the small light source and illumination cover like LED.

Many lighting devices mainly use incandescent bulbs and fluorescent lamps as light sources, but recently, those using LEDs with higher energy utilization efficiency as light sources have begun to spread.

JP 2008-140606 A JP 2010-192338 A

Glare is glare that is felt by lighting, and glare becomes stronger as “background brightness is lower”, “light source brightness is higher”, and “light source apparent area is larger”. On the other hand, not all of the brightness from the high-intensity light source becomes glare, and it may be used as one of lighting effects such as chandelier lighting.

However, in order to use glare as a production effect, there are many restrictions on the configuration of the lighting apparatus, and with the configuration of the conventional lighting device, it is difficult to produce a design-like shine and glitter while preventing unpleasant glare.

The present invention has been made in view of the above points, and an object of the present invention is to provide an illumination device capable of producing a design-like shine and glitter while preventing unpleasant glare.

According to the embodiment of the present invention, a lighting device includes a plurality of discretely arranged light sources, a cover that has light transmittance and covers the plurality of light sources, and a plurality of openings that are spaced apart. And an optical control film provided on the cover. According to the embodiment, the plurality of openings and the plurality of light sources are arranged irregularly with respect to each other. As an instrument structure, if the conditions of a light source and a cover are satisfy | filled, other parts can respond | correspond similarly to the conventional illuminating device.

FIG. 1 is a cross-sectional view of a planar illumination device according to the first embodiment. FIG. 2 is a plan view showing an arrangement of light sources of the planar illumination device. FIG. 3 is a plan view showing an opening pattern of a transflective layer of the planar illumination device. FIG. 4 is a diagram showing a luminance distribution when the cover is viewed from the front direction of the planar illumination device. FIG. 5 is a graph showing the brightness of the light emitting part felt by a person when the size of the light emitting surface (horizontal axis) and the luminance (vertical axis) change. FIG. 6 is a plan view of an optical control film showing various opening shape examples. FIG. 7 is a cross-sectional view of the illumination device according to the second embodiment. FIG. 8 is a diagram illustrating a luminance distribution when the cover is viewed from the front direction of the lighting apparatus according to the second embodiment. FIG. 9 is a cross-sectional view of the illumination device according to the third embodiment. FIG. 10 is a plan view showing an arrangement of light sources of the illumination device. FIG. 11 is a plan view showing an opening pattern of a transflective layer of the illumination device. FIG. 12 is a diagram illustrating a luminance distribution when the cover is viewed from an oblique direction of the lighting device. FIG. 13: is sectional drawing of the illuminating device which concerns on 4th Embodiment. FIG. 14A is a cross-sectional view of a lighting apparatus according to a fifth embodiment. FIG. 14B is a longitudinal sectional view of the illumination device according to the fifth embodiment.

Hereinafter, illumination devices according to various embodiments will be described in detail with reference to the drawings.
(First embodiment)
FIG. 1 is a cross-sectional view illustrating the planar illumination device according to the first embodiment.
The planar lighting device according to the first embodiment is a lighting device 10 in which a lighting fixture using a flat cover is provided with design characteristics of glitter and shine. That is, the lighting device 10 includes a substantially rectangular casing 2 having a bottom wall 2a and a side wall 2b erected along the periphery of the bottom wall, and a plurality of light sources 4 arranged on the bottom wall 2a of the casing. And a cover 5 covering the light source, and an optical control film 6 provided to face the surface of the cover 5. The cover 5 is formed in a flat rectangular plate shape, and the outer peripheral portion thereof is fixed to the upper end of the side wall 2 b of the housing 2. As a result, the cover 5 closes the upper opening of the housing 2 and faces the cover 5 with a gap substantially parallel to the bottom wall 2a. In the present embodiment, the cover 5 uses a transparent polymethyl methacrylate resin having light transmittance.

As shown in FIGS. 1 and 2, for example, LEDs are used as the light sources 4, and the plurality of light sources 4 are discretely arranged on the rectangular substrate 3 at a distance from each other. And the board | substrate 3 with which the light source 4 was mounted is being fixed on the inner surface of the bottom wall 2a. Specifically, the plurality of light sources 4 are arranged in a grid shape of 40 mm in a total of 5 rows and 8 columns in a grid pattern at intervals of 10 mm both vertically and horizontally.

As shown in FIGS. 1 and 3, the optical control film 6 has substantially the same size as the cover 5 and is provided over the entire inner surface of the cover 5. In the present embodiment, the optical control film 6 is formed on the inner surface of the cover 5 and faces the light source 4. The optical control film 6 has a large number of openings 7 arranged randomly. Here, random means, for example, that the horizontal and vertical coordinates of the opening 7 are defined by numerical values in a random number table in which the size of the cover 5 is the maximum number, so that an arbitrary number of openings 7 on the cover 5 It shows that they are arranged in a non-lattice form. In other words, by arranging the plurality of openings 7 with respect to the plurality of light sources 4 irregularly with respect to each other, an effect of irregular glittering described later is realized. That is, random means that the light source and the opening are in an irregular arrangement with each other, and the light source has a regular arrangement as in the embodiment, and the opening is a random arrangement using random numbers. On the contrary, even if the light source is messy or both sides are messy, they may be irregular. Specifically, the openings 7 are randomly arranged at a density at which one opening 7 is arranged at 20 mm 2 on average, and the openings 7 are circular with a diameter of 0.8 mm.

In the present embodiment, the optical control film 6 is a semi-transmissive diffuse reflection film, and is formed on the inner surface of the cover 5 by printing. Specifically, the optical control film 6 excluding the opening 7 has a semi-transmission property that diffuses and transmits one normal-direction incident light beam by 70%. The light beam that has passed through the optical control film 6 is diffused, and the light beam that has not passed through is again reflected inside the illumination device 1 and repeatedly enters the optical control film 6, and part of the light beam is diffusely transmitted. For this reason, the entire optical control film 6 emits light softly, and the opening 7 shines in a glittering manner according to the positional relationship with the plurality of light sources 4.

In addition, although the pattern which permitted the overlap was shown in FIG. 3, when the opening 7 is conspicuous due to the overlap, it is determined whether there is another opening 7 in the vicinity when the opening 7 is installed. An unacceptable pattern may be used. In this case, the specific enlargement of the opening 7 due to duplication can be prevented.

Further, the shape or area of the opening 7 may be randomly changed in accordance with the randomness of the position, or the region where the opening 7 is provided over the entire area of the cover 5 may be locally limited. The installation density of the openings 7 may be biased with respect to the entire area of the cover 5. These can be optimized in time according to the design of the lighting device 1.

When the average separation distance of the openings 7 is less than 2 mm, that is, when the average density is one or less per 4 mm 2, it is difficult to distinguish the adjacent openings 7 from each other, and the arrangement of the plurality of light sources 4 is increased by increasing the density. Can be seen. For this reason, it is desirable to secure an average separation distance of the openings of 2 mm or more.

The effect | action which the opening part 7 of the optical control film 6 shines with the structure mentioned above is demonstrated in detail below.
According to such a configuration, as shown in FIG. 1, for example, when the illumination device 10 is viewed from the viewpoint A, the opening 7 a among the many openings 7 is in a straight line with the viewpoint A and the light source 4. Positioned side by side, the light source 4 is directly viewed through the opening 7a, and a strong light is felt. On the other hand, since the light source 4 does not exist on the straight line connecting the opening 7b and the viewpoint A, the opening 7b does not feel light.

When the viewpoint is moved from the viewpoint A to the viewpoint B shifted in the horizontal direction, the viewpoint B, the opening 7b, and the light source 4 are arranged in a straight line, and the light source 4 is directly viewed through the opening 7b. Feel. On the other hand, since the light source 4 does not exist on the straight line connecting the opening 7a and the viewpoint B, light is not felt through the opening 7a. As a result, when the viewpoint is moved, the plurality of openings 7 are visually recognized so as to repeat blinking independently, and the lighting device 10 has a decorative effect in which various portions glitter and irregularly shine depending on the viewing position. FIG. 4 shows a luminance distribution when the cover 5 is viewed from the front direction.

In the present embodiment, the opening 7 is arranged over the entire cover 5, but the opening 7 can be arranged only in a partial region of the cover 5, and there is no problem in terms of function.
The brightness is determined by the size of the opening 7 and the luminance of the light source 4. FIG. 5 is a graph showing the brightness of the light emitting part that a person feels when the size (horizontal axis) of the light emitting part (light emitting surface) and the luminance of the light emitting part (vertical axis) change. In general, the luminance of the light emitting unit is determined by the design of the lighting device, and the size of the opening 7 is adjusted based on the determined light source luminance. The standard of adjustment is shown, for example, in the literature (Lighting Research and Technology March, Vol. 32, 19-26 (2000)). It is more efficient to check the lighting. Moreover, the brightness | luminance and lighting time of each luminescent spot can be changed by changing the magnitude | size of the opening part 7 within said restrictions, respectively.

The shape of the opening 7 can be arbitrarily changed as long as it is within the above constraints. FIG. 6 shows enlarged examples of various opening shapes of the opening 7. By combining an asymmetric shape as the shape of the opening 7, the brightness and lighting time of each bright spot can be changed depending on the direction of viewpoint movement.

The arrangement interval of the openings 7 is influenced by the arrangement interval of the light sources 4, but the blinking cycle of each light source accompanying the movement of the viewpoint becomes shorter as the arrangement interval becomes narrower. A blink that is too short can cause discomfort to the person. On the other hand, a lighting cycle that is too long makes it difficult to recognize blinking. Furthermore, if the aperture ratio becomes too high, there is a problem that the structure on the substrate 3 side can be directly visually recognized through the cover 5. Desirably, the arrangement interval of the openings 7 is designed so that the average blinking period of each bright spot is within a range of 0.1 to 1 second when the viewpoint is moved under an average observation condition. Specifically, this can be realized by setting the diameter of the opening 7 to 0.2 to 2.0 mm and the average distance of the opening 7 to 2 mm or more.

Also, the arrangement of the openings 7 may be a regular arrangement, but in this case, an irregular blinking effect can be obtained by making the arrangement of the light sources 7 non-uniform. By making the arrangement density of the openings 7 larger than the arrangement density of the light sources 4, the number of bright spots generated by one light source 4 is increased, and bright spots can be generated with a smaller number of light sources. Further, a transparent optical lens or microprism may be formed in the opening 7. For example, if it is a convex lens, it is possible to expand the light source range that can be viewed directly and increase the frequency and intensity of brightness to enhance the glittering feeling. It is possible to shine in a specific direction. The optical structure can be formed by printing with transparent special ink or hot press molding.

The optical control film 6 is semi-transmissive, but this is to allow light to be transmitted and extracted even in a region other than the opening 7 in order to increase the efficiency of the illumination device. In this case, the optical control film 6 can improve brightness uniformity other than the bright spot on the cover 5 by increasing the concealability. Further, by using a white pigment such as titanium oxide for the cover 5, an illumination device with high light utilization efficiency is obtained.

The optical control film 6 may be a high transmission scattering film made of scattering particles such as silica. In this case, the light use efficiency can be further increased. Even in this case, since the light passing through the optical control film 6 can reduce the straight light component by scattering, it is possible to obtain a shine feeling by the light transmitted through the opening 7.

Note that the optical control film 6 may be a complete reflection film or a light absorption film, but the light use efficiency is greatly reduced, so that it is not suitable for a lighting device for obtaining illuminance. The cover 5 is made of a transparent material, but the brightness ratio between the light that passes straight through the opening 7 and the light that passes straight through the optical control film 6 is within a range that satisfies the condition for obtaining a sense of brightness. The cover 5 may have diffusibility.

The optical control film 6 is formed on the inner surface of the cover 5, but may be disposed on the outer surface of the cover 5. However, in this case, since there is a high possibility that the optical control film 6 directly touches a person or an object, it is desirable to increase the strength and resistance of the optical control film. Although the optical control film 6 is directly formed on the surface of the cover 5, it may be separated from the cover 5, that is, provided with a gap from the surface of the cover 5. For example, what formed the optical control film 6 in the transparent sheet may be affixed on the cover 5, and in this case, the optical control film 6 can be easily replaced without replacing the cover 5. Alternatively, a reflection sheet may be used as the optical control film 6 and an opening 7 formed in the plane may be disposed.

The arrangement of the light sources 2 is not limited to the lattice shape, and any discrete arrangement can be used because the same operation and effect as described above can be obtained. The LED used as the light source 4 has a small light emitting area and is suitable as a point light source capable of obtaining a sense of brightness. In the case of lighting applications, white LEDs are generally used as LEDs as light sources. However, when a white light source configured by combining a plurality of LEDs having different emission colors such as blue, green, and red is used, the entire cover 5 is white configured by mixing the emission colors of the respective light sources as illumination. However, each flashing bright spot has a configuration in which a plurality of constituent colors flash irregularly, and an effect of changing the hue of the bright spot can be obtained.

From the above, according to the present embodiment, it is possible to obtain an illuminating device capable of providing a design-like shine and glitter while preventing unpleasant glare.
Next, a lighting device according to another embodiment will be described. In other embodiments to be described later, the same parts as those in the first embodiment described above are denoted by the same reference numerals, and detailed description thereof is omitted.

(Second Embodiment)
FIG. 7 is a cross-sectional view illustrating the lighting device according to the second embodiment. In the present embodiment, the cover 5 has a three-dimensional shape. That is, the illumination device 10 includes a bottom wall 2a that functions as the housing 2, a substrate 3 disposed on the bottom wall 2a, and a plurality of light sources 4 mounted on the substrate 3, and the cover 5 includes: It is fixed to the peripheral edge of the bottom wall 2 a and covers the light source 4. An optical control film 6 having a plurality of openings 7 is formed on the inner surface of the cover 5.

As described above, the optical control film 6 is disposed on the inner surface of the cover 5, and this can be created by forming the optical control film by an existing printing process and then molding the cover 5 by an existing thermoforming process. It is.

FIG. 8 shows a luminance distribution when the cover 5 is viewed from the front direction. By using the cover 5 having a three-dimensional shape, light can be extracted from the side surface, and light utilization efficiency is improved. Further, even when the lighting device 10 is viewed from the side, a sense of brightness is obtained, and there is an effect of widening the viewing angle at which the sense of brightness is obtained.

(Third embodiment)
FIG. 9 is a cross-sectional view showing an illumination device according to the third embodiment. In the present embodiment, the lighting device 10 is configured as a circular lighting device such as a household ceiling light. In this case, since the light emitting surface of the illuminating device 10 is circular, as shown in FIG. 10, the plurality of light sources 4 are arranged circumferentially on the annular substrate 3. A cover 5 covering the light source 4 is formed in a disc shape or an annular shape, and an optical control film 6 is provided on the inner surface of the cover 5. As shown in FIG. 11, the plurality of openings 7 of the optical control film 6 are randomly arranged according to the arrangement of the light sources 4.

According to this embodiment, the lighting device can be given a brilliant way of changing the shining position in accordance with the movement of the viewpoint by the same effect as the first embodiment described above. FIG. 12 shows a luminance distribution when the cover 5 is viewed from the illumination device 10 from an oblique direction.

(Fourth embodiment)
FIG. 13: is sectional drawing which shows the illuminating device which concerns on 4th Embodiment. The present embodiment is an example in which the lighting device is applied to a lighting device such as an LED bulb. According to this embodiment, the illuminating device 10 includes a base material 11 having a front surface portion, a base 12 attached to a lower end portion of the base material, a plurality of light sources 4 provided on the front surface portion of the base material, A substantially spherical cover 5 that covers the light source 4 and is attached to the base material, and an optical control film 6 that is provided on the inner surface of the cover and has a plurality of openings 7 are provided. The plurality of light sources 4 are discretely arranged on the front surface portion of the substrate 11.

After the cover 5 is printed with the optical control film 6 having the opening 7 on the substrate, the cover 5 having a desired shape including the optical control film 6 is formed by molding the substrate by thermoforming such as blower molding. be able to. Even in such a configuration, the effect described in the first embodiment can provide an illuminating device that shines in a sparkling manner in which the shining position changes corresponding to the movement of the viewpoint.

(Fifth embodiment)
FIG. 14A is a cross-sectional view of the lighting device according to the fifth embodiment, and FIG. 14B is a vertical cross-sectional view of the lighting device. This embodiment is an example applied to a tube type illumination device such as an LED fluorescent lamp. As shown in these drawings, the lighting device 10 includes a base material 11 having a front surface portion, a plurality of light sources 4 provided on the front surface portion of the base material, and substantially attached to the base material so as to cover the light sources 4. A cover 5 and an optical control film 6 provided on the inner surface of the cover and having a plurality of openings 7 are provided. The base material 11 has, for example, a semicircular cross section and is elongated and extends linearly or in a circle. The plurality of light sources 4 are arranged linearly or in a circle on the front surface of the substrate 11 and discretely arranged. The cover 5 is formed in an elongated cylindrical shape having a semicircular cross section. The cover 5 is attached to the front surface portion of the base material 11 and covers the light source 4.

As for the cover 5, after printing the optical control film 6 having the opening 7 on the substrate, the substrate 5 is formed by thermoforming such as vacuum forming, so that the cover 5 having the required shape including the optical control film 6 is created. be able to. Although the light sources 4 are discretely arranged on the front surface portion of the base material 11 made of, for example, metal, as shown in FIG. 14A, a plurality of light sources are not arranged in the cross-sectional direction of the tube. However, by arranging a plurality of openings 7 in the circumferential direction of the cover 5, a bright spot blinking effect can be obtained. As shown in FIG. 14B, with respect to the tube length direction, a plurality of light sources 4 are arranged, and due to the effect described in the first embodiment, the lighting device has a glittering way of changing the shining position corresponding to the movement of the viewpoint. Can be given.

The lighting devices according to the second to fifth embodiments described above have a simple structure, can be applied to various lighting devices, and can provide the effect of irregularly blinking bright spots. In the illumination device according to the above-described embodiment, the brightness of each bright spot greatly varies with the movement of the viewpoint, so that it is possible to obtain an illumination effect that repeatedly blinks irregularly, and a decorative effect that is more easily recognized by the human eye. Can be fed into the device. Thereby, according to the 2nd thru | or 5th embodiment mentioned above, similarly to 1st Embodiment, obtaining the illuminating device which can produce the brightness and glittering feeling with a design property, preventing an unpleasant glare. Can do.

The present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

Claims

A plurality of discretely arranged light sources;
A cover having light transparency and covering the plurality of light sources;
An optical control film provided on the cover, having a plurality of openings provided apart from each other;
A lighting device comprising:
The lighting device according to claim 1, wherein at least one of the plurality of openings of the optical control film and the plurality of light sources is irregularly arranged with respect to the other arrangement. .
3. The illumination apparatus according to claim 2, wherein the optical control film is a semi-transmissive film, and main illumination of the illumination apparatus is performed through the optical control film.
The lighting device according to claim 2, wherein the opening is provided in a larger number than the plurality of light sources.
The lighting device according to any one of claims 1 to 4, wherein an average diameter of the openings is 0.2 to 2.0 mm.
The lighting device according to any one of claims 1 to 4, wherein an average separation distance of the openings is 2.0 mm or more.
The illuminating device according to any one of claims 1 to 4, wherein the optical control film is formed on a surface of the cover.
The lighting device according to any one of claims 1 to 4, wherein the opening has a non-rotationally symmetric shape.
The lighting device according to any one of claims 1 to 4, wherein a lens or a prism is provided in the opening.