JPH02242504A - Luminaire - Google Patents

Abstract

PURPOSE:To make it possible to emit light which is converted into one with higher colour temperature with good efficiency and without damaging light rendering properties by forming on the surface of a reflector an optical multi-layer film which reflects light while converting its colour temperature into a higher one, and also causing the reflector to have its maximum reflectance less than a specific wavelength. CONSTITUTION:The luminaire includes a light source 6 and a reflector 5 disposed optically opposite to the light source 6, and the reflector 5 has an optical multi-layer film 12 formed on its surface which film reflects light incident thereon from the light source 6 while converting the colour temperature of the light into a higher one, and the reflector 5 is made to have its maximum reflectance in the range of more than 430nm to less than 500nm. The optical multi-layer film 12 comprises, e.g., a titan oxide (TiO2) film layer 13 of high refractive material and a silicon oxide (SiO2) film layer 14 of low refractive material alternately laminated on each other, and reflects light of the light source 6 while converting it into light with a colour temperature higher than that of the light of the light source 6 by means of the thickness and number of films of each film layer 13, 14. It is thus made possible to obtain a luminaire of high illuminance efficiency and which emits reflected light while converting the light into one with higher colour temperature without damaging light rendering properties.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to lighting equipment such as spotlights, and is particularly applicable to lighting equipment such as spotlights that are used in lighting facilities suitable for store lighting. This invention relates to a reflector for a device that emits light.

(Prior art) Conventional spotlights that emit light with a high color temperature of this type use a filter that converts the colored light of the light source into a high color temperature, and the light that passes through this filter is converted into a high color temperature. A configuration was adopted in which the light was output as illumination light.

(Problem to be solved by the invention) In the spotlight using the above conventional filter, the sixth
As shown in the figure, the filter that converts transmitted light into a high color temperature has a wavelength of 400 nm that exhibits the maximum transmittance within the range of 400 nm to 700 nm+, and has the problem of poor illuminance efficiency. Ta.

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a lighting fixture that has high illuminance efficiency, converts the color temperature to a high color temperature, and emits reflected light without impairing color rendering properties.

[Structure of the invention]

(Means for Solving the Problems) A lighting fixture of the present invention includes a light source and a reflector disposed optically opposite to the light source, and the reflector has a surface that receives light incident from the light source. The invention is characterized in that an optical multilayer film is formed that reflects the color temperature of light converted to a high color temperature, and the reflectance of this reflector has a maximum reflectance in the range from 430 nm to 500 ++ m. It is something.

(Function) In the lighting equipment of the present invention, the light that enters the reflector from the light source is emitted after being reflected by the optical multilayer film with a high color temperature.
Color rendering properties are not impaired, and there is little decrease in illuminance efficiency.

(Example) The configuration of an embodiment of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a main body of the apparatus, which is mounted on the tip of a support 2 that is attached to a structure such as a ceiling surface so that its horizontal and vertical directions can be adjusted. A lamp socket 3 is provided approximately at the center of the front surface of the appliance body 1. Further, a substantially cylindrical shade 4 is attached to the front side of the instrument main body 1, and a reflector 5 is fitted and held in this shade 4.

The reflector 5 contains a light source 6 such as a single-end halogen lamp mounted on the lamp socket 3, has an irradiation opening 7 on the front surface, and is arranged to optically face the light source 6 in the parentheses. 6 is reflected and emitted from the front illumination opening 7 of the reflector 5. Further, a substantially cylindrical holder 8 for holding the reflector 5 is provided in the front opening of the shade 4.

As shown in FIG. 2, the reflector 5 includes a substrate 10 made of a metal such as aluminum, a synthetic resin, or an opaque material such as ceramic, and a surface of the substrate 10 coated with titanium carbide, titanium carbide, etc. It consists of a light-absorbing layer 11 made of silicon carbide or a chromium compound, and an optical multilayer film 12 formed on the surface of this light-absorbing layer 11.
An optical multilayer film that converts the color temperature of light incident from
It has a maximum reflectance below 00 nm. The optical multilayer film 12 is made of, for example, a titanium oxide (TiO2) film layer 13 made of a high refractive material and a silicon oxide (Sin oxide) film layer 13 made of a low refractive material.
2) The film layer 14 is constructed by laminating each film layer alternately, and the thickness of the film layers 13 and 14 and the number of layers make the light from the light source 6 have a color temperature higher than that of the light from the light source 6. It converts the temperature into colored light and reflects it.

In the embodiment described above, the reflector 5 is a substrate 10 made of a non-transparent material.
However, as shown in FIG. 3, a substrate 10 made of a transparent material such as glass or synthetic resin, and this substrate
For example, a titanium oxide (TiO2) film layer 13, which is a high refractive material, and a silicon oxide (SiO2) film layer, which is a low refractive material, are formed on the surface of the
n2) It is also possible to construct the optical multilayer film 12 in which the film layers 14 and each film layer are alternately laminated.

Next, the operation of this embodiment will be explained.

Light from a light source 6 of a lighting fixture such as a spotlight attached to the ceiling of a structure is incident on a reflector 5,
The reflected light is reflected by the optical multilayer film 12 of the reflector 5 as colored light having a color temperature higher than that of the light from the light source 6, and is emitted from the irradiation aperture 7. The reflectance of the light reflected by this optical multilayer film 12 has a maximum reflectance of 430 nm or more and 5C) Onm or less, and the decrease in illuminance is small (color rendering properties are not impaired).

That is, when the light source 6 is a halogen lamp with a color temperature of 2850 K, as light is removed from the short wavelength side, the illuminance starts to decrease at 500 nm, as shown by characteristic curve A in Figure 4, and its average color rendering Since the evaluation number starts to decrease around 430 nm as shown by characteristic curve B in FIG.
It is assumed that color rendering properties are not impaired.

The optical multilayer film 12 has a film thickness as shown in the following table, for example, where n is the refractive index, d is the actual film thickness, and λ0 is the control wavelength.

(See next page below) The spectral reflectance (at the time of vertical incidence) has a maximum reflectance at 470 nm, as shown in FIG.

In a lighting fixture in which a 12V 100W piece 1-1 metal halogen lamp is used as the reflector 5 in which the optical multilayer film 12 is formed on the glass substrate 10, the color temperature of the irradiated light is 3800, and the color rendering index (Ra) is is 90, and the illuminance is reflectance 8
The color rendering index (Ra) is about 6% compared to the 5% aluminum reflector, and in the case of equipment using conventional filters, the color rendering index (Ra)
is 93, and the illuminance is 52%, so the color rendering index is hardly impaired and the decrease in illuminance is small.

〔Effect of the invention〕

According to the present invention, an optical multilayer film is formed on the surface of the reflector to reflect the color light that has been converted from the color temperature of the light incident from the light source to a high color temperature, and the reflectance of the reflector is 430 nm or more and 500 nm or more. Since it has the maximum reflectance below nm,
It has good efficiency and emits light converted to a high color temperature without impairing color rendering properties.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view of a lighting fixture showing one embodiment of the present invention, Fig. 2 is an enlarged sectional explanatory view of a part of the same reflector, and Fig. 3 shows another embodiment. An enlarged cross-sectional explanatory diagram of a part of the reflector, FIG. 4 is a characteristic diagram of spectral reflectance, efficiency, and color rendering of the same reflector as above, FIG. 5 is a characteristic diagram of spectral reflectance of the same reflector as above, and FIG. FIG. 3 is a spectral transmittance characteristic diagram of a conventional filter. 5. Reflector, 6. Light source, 12. Optical multilayer film. March 1-6, 1989 Inventor: Tatsuo Maruyama

Claims (1)

[Claims] (1) A light source and a reflector disposed optically opposite to the light source, the reflector having a surface that reflects colored light obtained by converting the color temperature of the light from the light source to a high color temperature. A lighting device comprising an optical multilayer film formed thereon, the reflector having a maximum reflectance in a range of 430 nm or more and 500 nm or less.