JP2000100222A - Lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniform the brightness of a globe surface with a simple method to improve a practical irradiation characteristic and to improve the appearance from the viewpoint of design by relating the light transmittance of a globe that is a non-transparent and light dispersing external member generally proportionally to the distance from a light source so as to set it differently. SOLUTION: Regarding the thickness of a globe, a part 1a nearest to a light source 2 is thickest, a part 1b farther than the part 1a is thinner than the part 1a, and a still farther part 1c is thinner than the part 1b. That is, the thickness of the globe is so set that the globe thickness at the part nearest to the light source 2 is the maximum, and the thickness of its peripheral part is gradually reduced as it parts away from the thickest part. The light emitted from the light source 2 is irradiated through the globe arranged around the light source 2. Thereby, the brightness of the globe surface is uniformed and a uniform luminous intensity distribution can be provided regardless of the distance between the light source 2 and the globe.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a luminaire having a globe, which is a light-diffusing outer member that is not completely transparent and covers a substantially point light source such as a light bulb, and is mounted on an indoor ceiling or wall. It is suitably used for lighting equipment.

[0002]

2. Description of the Related Art Many gloves of conventional lighting fixtures are used for shielding internal components such as point light sources from the outside and for diffusing light to emit gentle light. The material forming the light emitting portion is made of a non-transparent, light-diffusing milky white material, or the surface of the material is made a diffuse reflection surface. However, the color, thickness, and properties of the light diffusing surface of the material were constant, and thus, the optical transmittance for irradiation light emitted from an internal light source was uniform throughout the glove.

[0003]

Since the light transmittance of the gloves of the conventional lighting equipment as described above is uniform, if the distance of the gloves from the approximate point light source is different, an extreme example is a rectangular parallelepiped shape. However, the brightness of the globe surface is determined in inverse proportion to the distance from the point light source in the globe. This can be said from the inverse square law in which the illuminance is inversely proportional to the square of the distance, and will be described in detail below with reference to the drawings.

In FIG. 3, the luminous intensity of the light source is I (cd),
The distance from the light source to the inner surface near the globe 7a
S1 (m), the inner surface illuminance of that part is E7a (lx),
Distance to inner surface near globe 7c farther than lobe 7a
Is S2 (m), and the inner surface illuminance of that part is E7c (lx).
I do. Globe inner illuminance E7a, E7c is calculated by the inverse square method.
From the rule, it can be expressed by the following equation. E7a = I / S1^Two(Lx) E7c = I / S2^Two(Lx)  Since S1 <S2, E7a> E7c, and
The inner surface near the globe 7c is darker than the inner surface near the glove 7a.
Will be.

Next, the brightness of the outer surface near the globe 7a and the outer surface near the globe 7c will be described below. As described above, the conventional light-diffusing glove has the same transmittance, so that the minute surface is a perfect diffusion surface. If the transmittance is τ, the brightness L7a (cd
/ M ² ) and the outer surface luminance L7c near the globe 7c
(Cd / m ² ) can be expressed by the following equation. L7a = τE7a / π (cd / m ² ) L7c = τE7c / π (cd / m ² ) Since E7a> E7c as described above, L7a>
L7c, and the outer surface near the glove 7c is the glove 7a.
The brightness will be lower than the nearby outer surface. That is, the outer surface near the globe 7c looks dimer than the outer surface near the globe 7a.

Further, since luminance is the area density of luminous intensity, luminance is proportional to luminous intensity. Therefore, the L7a
> L7c, the luminous intensity I near the globe 7c
7c is lower than the luminous intensity I7a near the globe 7a. That is, uniform light distribution cannot be obtained.

[0007] From the above, according to the prior art, since the brightness of the glove surface is not uniform, when the user looks at the lighting fixture, the brightness of the glove surface is not uniform and the design is good. I couldn't say. Further, the illuminance of the object to be illuminated also varies greatly depending on the location, and there is a problem that it is not possible to obtain the brightness required for practical use in a direction where the distance from the point light source is far away.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a lighting device which has a good irradiation characteristic in practical use or a good appearance even in design by a simple method. Is to do.

[0009]

In order to achieve the above object, a first aspect of the present invention is to provide a glove which is a non-transparent light-diffusing outer member for covering a lighting fixture, wherein the light transmittance of the glove is determined by the light source. The globe surface is made to have a uniform brightness and a uniform light distribution, because the globe surface is made different in relation to the distance from the object.

To achieve the above object, the means for varying the transmittance is thick, the thickness of the globe closest to the light source is the maximum thickness, and the thickness of the peripheral portion is
That is, the thickness is gradually or gradually reduced as the distance from the maximum thickness portion increases. In contrast to this measure, since the transmittance is substantially inversely proportional to the thickness, the brightness of the globe surface is uniform, and a uniform light distribution can be obtained.

According to a third aspect of the present invention, the means for varying the transmittance is the depth of the grain, the globe grain depth closest to the light source is maximized, and the grain depth of the periphery is: This means that the grain depth is gradually or gradually reduced as the distance from the maximum grain depth increases. In contrast to this measure, the deeper the grain depth is, the more the irregular reflection of light increases and the transmittance decreases.In other words, since the transmittance is approximately inversely proportional to the grain depth, the brightness of the glove surface is uniform,
Even light distribution can be obtained.

In order to achieve the above object, it is preferable that the means for making the transmittance different be the roughness of the grain pattern, the globe grain pattern closest to the light source be the minimum roughness, and the grain pattern of the periphery thereof be reduced. That is, as the distance from the grained portion having the minimum roughness is increased, the grained pattern is gradually or gradually made coarser. In contrast to this measure, the rougher the roughness, the less the irregular reflection of light and the higher the transmittance. In other words, since the transmittance is approximately proportional to the roughness, the globe surface has a uniform brightness and uniform distribution. Light is obtained.

In order to achieve the above object, it is preferable that the means for changing the transmittance is a light-diffuse milky white color having a light-diffusive color, and the light-diffuse milky white of the glove closest to the light source. Assuming the maximum density, the milky white density in the periphery thereof means that the milky white density is gradually or stepwise reduced as the distance from the maximum milky white density part increases. In contrast to this measure, since the density of the milky white color is substantially proportional to the transmittance, the brightness of the globe surface is uniform, and a uniform light distribution can be obtained.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a side sectional view of a part of a lighting device according to the first and second embodiments of the present invention.
In FIG. 1, reference numeral 1 denotes a non-transparent, light-diffusing milky white glove, which is arranged around a light source 2 and is attached to a mounting base 5 by a screw-in system and can be attached and detached.
A packing 4 such as an O-ring for waterproofing, moisture-proofing, and dust-proofing is sandwiched between the and the mounting base. The light source 2 is screwed into a socket 3, and the socket 3 is provided with a power supply line 6 that is electrically connected. Regarding the thickness of the globe 1, the portion 1a closest to the light source is the thickest, the portion 1b farther from the light source 1b is thinner than the portion 1a, and the portion 1c farther from the light source is thinner than the portion 1b. In other words, the thickness of the globe 1 is set such that the thickness of the globe closest to the light source is the maximum thickness, and the thickness of the peripheral portion gradually becomes thinner as the distance from the maximum thickness portion increases.

Next, the operation of the lighting device will be described. Light emitted from the light source 2 is applied through a globe 1 disposed around the light source 2. The portion of the glove 1a closest to the light source has an appropriate milky white density and thickness set in advance, and is irradiated with appropriate light. In the globe 1b, the distance from the light source is longer than that of the globe 1a.
Since it is thinner and thicker than the globe 1a, the transmittance is higher, the brightness is improved, and the brightness is about the same as that of the globe 1a. The globe 1c is farther from the light source than the globe 1b, so it tends to be dim when the thickness is the same, but since the thickness is thinner than the globe 1b, the transmittance is higher and the brightness is improved. And the brightness is about the same as that of the globe 1b.

As described above, the thickness of the globe closest to the light source is the maximum thickness, and the thickness of the peripheral portion is gradually reduced as the distance from the maximum thickness increases. Irrespective of the distance to the globe, the brightness of the globe surface is uniform, and a uniform light distribution can be obtained.

Next, a lighting device according to a third, a fourth and a fifth embodiment of the present invention will be described. The structure of the lighting device is the same as that of the other parts except for the globe 1.
The details of the glove 1 will be described below because it is similar to 1.

In the case of the second embodiment, the means for making the transmittance different is the thickness of the globe 1, but the third, fourth,
In the case of the fifth embodiment, the thickness is the same, and the transmittance is made different by another means.

In the third embodiment, the means for making the transmittance different is the grain depth, the grain depth of the globe 1 closest to the light source is the largest, and the transmittance is the lowest.
As the grain depth at the periphery is gradually or gradually reduced as the distance from the maximum grain depth increases, the transmittance is gradually or gradually increased. .

In the fourth embodiment, the means for varying the transmittance is the roughness of the grain pattern, the grain pattern of the globe 1 closest to the light source is set to the minimum roughness, and the grain pattern of the peripheral portion is set. The transmittance is gradually or gradually increased as the distance from the grained pattern portion having the minimum roughness gradually increases or gradually increases gradually. Regarding the grain pattern, FIG. 2A shows a rough grain pattern when compared at the same magnification, and FIG. 2B shows a grain pattern that is less coarse than that.

In the fifth embodiment, the means for making the transmittance different is a light-diffusing milky white color,
The light-diffusing milky white color of the globe 1 closest to the light source is the maximum density, the transmittance is the lowest, and the milky white density in the periphery is the farther from the maximum milky whiteness part. Due to the gradual or stepwise reduction of the milky white density, the transmittance is gradually or stepwise increased.

As in the case of the above-described second embodiment, the illuminating device is also configured such that the further away from the light source, the more the globe becomes.
Since the transmittance of 1 is high, the same effect is obtained, that is, the brightness of the globe surface is uniform regardless of the distance between the light source and the globe, and a uniform light distribution is obtained.

Although the embodiments of the present invention have been described independently, overlapping implementations are also applicable.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a part of a lighting device according to first and second embodiments of the present invention.

FIG. 2 is a grain pattern when an enlargement magnification is equal according to a fourth embodiment of the present invention.

FIG. 3 is a cross-sectional side view of a part of a conventional lighting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glove 2 Light source 3 Socket 4 Packing 5 Mounting base 6 Power line 7 Globe in conventional lighting equipment I Luminous intensity S Distance from light source to globe E Luminance inside glove L Luminance

Claims (5)

[Claims] 1. A lighting device, wherein a light transmittance of a glove which is a non-transparent light-diffusing outer member for covering a lighting device is made to vary substantially in proportion to a distance from the light source. 2. The means for varying the transmittance is thick, the thickness of the globe closest to the light source is the maximum thickness, and the thickness of the periphery is gradually increased as the distance from the maximum thickness increases. 2. The lighting device according to claim 1, wherein the lighting device is formed to have a small thickness in a stepwise manner. 3. The means for making the transmittance different is the depth of the grain, wherein the depth of the glove grain closest to the light source is maximized, and the depth of the grain in the peripheral portion increases as the distance from the maximum grain depth increases. The lighting device according to claim 1, wherein the embossing depth is gradually or gradually reduced. 4. The means for making the transmittance different is the roughness of the grain pattern, wherein the glove grain pattern at the portion closest to the light source has the minimum roughness, and the grain pattern at the periphery thereof is from the grain pattern having the minimum roughness. 2. The lighting device according to claim 1, wherein the texture is gradually or gradually increased as the distance increases. 5. The means for varying the transmittance is a light-diffuse milky white color density, the light-diffusible milky white color of the globe closest to the light source is made the maximum density, and the milky white color at the periphery thereof 2. The lighting device according to claim 1, wherein the density of the milky white is gradually or gradually reduced as the distance from the maximum milky white density part increases.