JPH04292801A - Indoor lighting device - Google Patents

Abstract

PURPOSE:To obtain nearly natural and comfortable lighting environment even at closed space by keeping the correlation color temperature of a light source emitting high directivity light lower than the color temperature of a light source emitting diffused light. CONSTITUTION:A light source 2 to emit high directivity light 6 is used to maintain approximately 2000lx illuminance E1 on a floor 1 and the correlation color temperature K1 of the light source 2 is kept equal to or below 5500K, thereby obtaining the feeling of lighting color near direct sunlight. Also, illuminance E2 on the floor 1 is maintained approximately at 500lx, using a light source 3 to emit diffused light 5, and the correlation color temperature K2 of the light source 3 is kept at a value of between 6000 K and 11000 K, thereby obtaining the feeling of lighting near sunlight from the blue sky. Namely, relationships of K1<K2, and E1/10<=E2<=E1/3 are maintained, and the side of an indoor object faced to the light source 2 is mainly exposed to a large beam therefrom, and a shade area thereby generated is exposed to light from the light source 3. According to this construction, the illuminance E2 on the floor 1 due to the light source 3 becomes 1/4 of the illuminance E1 due to the light source 2, thereby obtaining shade feeling under daylight from the blue sky.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an indoor lighting system, and more particularly to an indoor lighting system using two types of light sources with different illumination characteristics.

0002

[Prior Art] In places with relatively high ceilings, such as gymnasiums, hotel lobbies, underground passageways and plazas, high-pressure sodium lamps and metal halide lamps are used in combination, for example.
Indirect lighting using fluorescent lamps and direct lighting using light bulbs are often used together. The combination of high-pressure sodium lamps and metal halide lamps is characterized by the fact that high-pressure sodium lamps have poor color rendering properties but high lamp efficiency.
Metal halide lamps have low lamp efficiency but good color rendering properties, so by using them together, we can take advantage of the benefits of both and secure relatively good color rendering properties and the necessary brightness with as little power as possible. (for example, Lighting, edited by the Illuminating Engineering Society of Japan)
Handbook, P29 (1984)). On the other hand, when using a combination of indirect lighting using fluorescent lamps and direct lighting using light bulbs, the former provides general brightness while suppressing unpleasant glare, while the latter creates locally bright areas to focus on what is needed. The purpose is to create a changing atmosphere by showing off or giving a sense of sparkle (for example, edited by the Illuminating Engineering Society of Japan,
Lighting Handbook, P434 (19
84)).

[0003] On the other hand, recently, there has been an increasing need to obtain a light environment close to nature in relatively large-scale indoor spaces and underground spaces, or in other words, to obtain a light environment close to that outdoors on a sunny day. There is. However, the above-mentioned conventional methods cannot meet the need for ``a light environment similar to the outdoors on a sunny day'' even in terms of their purpose.

As is well known, outdoor light on a clear day consists of direct light from the sun and diffused light from the blue sky. Therefore, the part of an outdoor three-dimensional object facing the sun is illuminated by direct sunlight, and the part in the shadow caused by the direct light is illuminated by diffused light from the blue sky. For example, a daytime scene projected on a movie screen looks like daytime even though the illuminance of the screen surface is much lower than the outdoor illuminance during the day, so direct sunlight illuminates the part facing the sun. If we can reproduce the ratio of the illuminance of direct light to the illuminance of diffused light from the blue sky that illuminates the shadow areas, and the correlated color temperature of direct sunlight and the correlated color temperature of diffused light from the blue sky in indoor spaces, we can create a "natural" It is thought that a similar light environment can be obtained.

[0005] Since the correlated color temperature when direct sunlight and diffused light from the blue sky are combined is approximately 6500K, fluorescent lamps with a correlated color temperature of 6500K have recently been put into practical use (Toshiba Lighting & Technology Co., Ltd.). KK)). However, because the shadow areas are illuminated by diffused light from the blue sky and not by composite light, this lamp does not give the feeling of a natural light environment as described above.

[0006]

[Problems to be Solved by the Invention] These problems are that both highly directional light equivalent to direct sunlight and diffused light equivalent to light from the blue sky have not been achieved, and that both direct light and diffused light have not been achieved. The reason is that the ratio of illuminance due to light and the correlated color temperature are not similar to the daytime light environment outdoors on a clear day.

An object of the present invention is to provide an indoor lighting device that solves the above-mentioned problems, creates a lighting environment close to nature, and creates a comfortable living space similar to that outdoors even in closed spaces such as underground spaces. do.

[0008]

[Means for Solving the Problems] To achieve this object, the present invention includes a light source that emits highly directional light that is placed in the upper part of the room, and a light source that emits diffused light that is placed around the light source. In an indoor lighting device comprising a light source, (1)
The correlated color temperature K1 of a light source that emits highly directional light and the correlated color temperature K2 of a light source that emits diffused light are configured so that K1<K2. (2) In addition to 1, the illuminance E1 of the light source that emits highly directional light and the illuminance E2 of the light source that emits diffused light are configured to satisfy E1/10≦E2≦E1/3. (3) Furthermore, the correlated color temperature K1 of the light source that emits highly directional light is 5500K or less, and the correlated color temperature K2 of the light source that emits diffused light is 6000K or higher.

[0009]

[Function] In an indoor lighting system that has a light source placed at the top of the room that emits highly directional light and a light source that radiates diffused light around this light source, the highly directional light is directly rays of the sun. Diffused light has an effect equivalent to that of blue sky light. In such an indoor lighting system, by varying the correlated color temperature of highly directional light and the correlated color temperature of diffused light, we conducted a subjective evaluation experiment to find a combination of correlated color temperatures that would provide a state close to the outdoor lighting environment. Ta. As a result, it was found that by setting the correlated color temperature of highly directional light to 5500K or less and setting the correlated color temperature of diffused light to 6000K or more, a state almost similar to an outdoor light environment can be obtained. moreover,
It has been found that by setting the correlated color temperature of highly directional light to 4,000 to 5,500 K and the correlated color temperature of diffused light to 10,000 to 15,000 K, a state even closer to the outdoor light environment can be obtained. This means that the correlated color temperature of actual direct sunlight and blue sky light is 3500 to 5500 K, respectively.
, 6000 to 20000K.

In addition, by varying the ratio of the illuminance of highly directional light to the illuminance of diffused light, a subjective evaluation experiment was conducted to determine the combination ratio of illuminance that would provide a sense of shade close to that of an outdoor light environment. As a result, the ratio (E2/E1) of illuminance E1 due to highly directional light to illuminance E2 due to diffused light is 1/10 to 1.
/3, it was found that a sense of shade close to the outdoor light environment could be obtained. This means that the illuminance Eb due to actual direct light
and the illuminance Es due to blue sky light (Eb/Es) is 1/1
This is also inferred from the fact that it is 4 to 1/3.

As described above, by setting the ratio of illuminance between highly directional light and diffused light and the correlated color temperature to predetermined values, it is possible to provide a light environment with the same psychological sensation as outdoors on a clear day. .

0012

[Example] Specific examples will be described in detail below. FIG. 1 shows an indoor lighting device of the present invention, and FIG. 2 is a plan view. Figures 1 and 2 are examples of installation in a laboratory assuming a hotel lobby with a floor area 1 measuring 7m x 7m. Figures 1 and 2
2 is a light source that emits highly directional light, consisting of a medium-square light distribution floodlight with a built-in metal halide lamp (manufactured by Matsushita Electric Industrial Co., Ltd., output 2000W, correlated color temperature 5500K, luminous flux 180,000 lumens). , installed on the ceiling slightly closer to the wall than the center of the ceiling. 3 in Figures 1 and 2 is a light source that emits diffused light, and is a straight tube fluorescent lamp (Matsushita Electric Industrial Co., Ltd.).
Made in Japan, output 40W, correlated color temperature 11000K, luminous flux 170
0 lumens). In order to further increase the degree of diffusion of light from the light source 3 that emits this diffused light, it was attached so as to form a light ceiling in combination with a milky white panel 4 made of resin.

[0013] An illumination intensity of about 2000 lx is obtained on the floor surface 1 by the light source 2 which emits highly directional light. Furthermore, since the correlated color temperature is 5500K, a light color that feels close to direct sunlight is obtained. A light source 3 emitting diffused light provides an illuminance of about 500 lx on the floor 1. Furthermore, since the correlated color temperature is 11,000K, a light color that feels close to blue sky light is obtained. The part of the indoor object that faces the light source 2 that emits highly directional light is mainly exposed to the light source 2 that emits highly directional light with a large luminous flux.
The shadow area caused by this is illuminated by the light source 3 which emits diffused light. The illuminance of the floor surface 1 by the light source 3 that emits diffused light is 1/4 of the illuminance of the floor surface 1 caused by the light source 2 that emits highly directional light, and an approximate sense of shadow can be obtained under daylight on a clear day. Ta.

[0014] In the above explanation, the explanation has mainly been given using a hotel lobby of a predetermined size as an example, but it goes without saying that the present invention can also be applied to indoor spaces of other shapes.

[0015]

As described above, the present invention provides an indoor lighting system comprising a highly directional light source and a light source that emits diffused light. By creating a predetermined difference in the correlated color temperature and the resulting illuminance, a comfortable lighting environment close to nature can be obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view of an indoor lighting device according to an embodiment of the present invention.

[Figure 2] Plan view of the device

[Explanation of symbols]

1　Floor surface 2. Light source that emits highly directional light 3. Light source that emits diffused light 4 Milky white panel 5 Diffused light 6. Strongly directional light 7 Ceiling 8 Wall surface 9 Milky white panel support material

Claims (3)

[Claims] [Claim 1] Components include a light source that emits highly directional light placed in the upper part of the room, and a light source that radiates diffused light placed around the light source, and emits highly directional light. An indoor lighting device in which a correlated color temperature K1 of a light source and a correlated color temperature K2 of a light source that emits diffused light satisfy K1<K2. 2. The indoor lighting device according to claim 1, wherein the illuminance E1 of the light source emitting highly directional light and the illuminance E2 of the light source emitting diffused light satisfy E1/10≦E2≦E1/3. . 3. The indoor lighting device according to claim 1, wherein the light source that emits highly directional light has a correlated color temperature K1 of 5500K or less, and the light source that emits diffused light has a correlated color temperature K2 of 6000K or more.