JPH10302723A - Metal halide lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lamp having a specific range of the color temperature, an average color rendering evaluation number and chromaticity coordinates, and further having the capability of lighting an irradiated object with good blue light and improving even color rendering properties around the irradiated object by applying the constitution that a multilayer light interference film for specifying a light transmission factor characteristics in a specific wavelength zone is formed on the surface of a heat resistant cylindrical body laid on the external surface of a luminous tube sealing specific metal and gas inside. SOLUTION: A heat resistant cylindrical body 2 is laid on the external surface of a luminous tube 1 containing the iodide of dysprosium, neodymium and cesium, and mercury and rare gas sealed inside. A multilayer light interference film 3 is formed out of the metallic oxide of TiO2 , and SIO2 on the surface of the heat resistance cylindrical body 2, and has a light transmission factor characteristic of 50% or more, 20% or less and 0 to 50% in the respective wavelength zones of visible rays having wavelength of 380 nm to (510±10nm), 700 to 780 nm, and others. In addition, the color temperature of a lamp is between 6000 K and 7000 K, and an average color rendering evaluation number is equal to or above 95. Also, the chromaticity coordinates of the lamp are taken as X between 0.215 and 0.225 and Y between 0.18 and 0.22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a metal halide lamp, and more particularly to a metal halide lamp having improved blue color rendering as a color characteristic of the lamp.

[0002]

2. Description of the Related Art In general, metal halide lamps have better emission efficiency and color rendering properties than high-pressure mercury lamps by enclosing a metal iodide together with mercury and a rare gas in a quartz arc tube and emitting the metal iodide. Has lamp characteristics. In addition, compact metal halide lamps having a short arc length contain various additives, are further improved in color temperature and color rendering, and are used for general store lighting.

[0003] Of the above metal halide lamps, 100
Lamps with a high color temperature of 00K or higher have inferior color rendering properties as compared with lamps with a low color temperature and a medium color temperature.
With blue irradiation light in a wavelength range of nm to 500 nm,
It is used as a lamp for show-up lighting in a store or as an aquarium effect lighting. Here, in order to achieve a high color temperature in blue, indium iodide and mercury are used as additives to be sealed in the arc tube, and 455 nm of the indium is used.
Near emission and mercury 403nm, 435nm, 546n
Lamps that utilize m emission have been proposed.

[0004]

However, it is difficult to obtain a lamp that emits blue light with good color rendering properties, because the lamp uses a line spectrum of indium and mercury. Also, in the case of show-up illumination of an object to be illuminated, it is necessary not only to irradiate the object with blue light but also to illuminate the periphery of the object to be illuminated. It becomes a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and provides a metal halide lamp having good color rendering properties and a blue emission characteristic. In addition, the color rendering properties around the irradiated object can be improved. In addition, a metal halide lamp that is effective as a light source for aquarium lighting, which can provide a blue color exhibiting effective color rendering for store show-up lighting and aquarium effect lighting, and further contains a large amount of wavelength components having a high underwater transmittance of 450 nm to 550 nm. The purpose is to provide.

[0006]

In order to achieve the above object, the present invention provides a lamp having a color temperature of 6000K to 7000K.
K, an arc tube enclosing at least dysprosium, neodymium, and cesium iodide, mercury, and a rare gas so that the average color rendering index is 95 or more; and a heat-resistant cylinder around the arc tube. Is arranged on the surface of the cylindrical body.
composed of a metal oxide of iO ₂ and SiO ₂ , and 380
50% in the wavelength region of nm to (510 ± 10 nm)
Forming a multilayer light interference film having the above light transmittance, light transmittance of 20% or less in a wavelength region of 700 nm to 780 nm, and light transmittance of 0 to 50% in a wavelength region of other visible light; The tube and the cylindrical body are held in the outer sphere, and the chromaticity coordinates are X = 0.215 to 0.2 as lamp characteristics.
225, wherein Y = 0.18 to 0.22.

[0007] A white light having good color rendering properties due to emission of the above-mentioned dysprosium, neodymium and cesium iodides and mercury is formed on the surface of a heat-resistant cylinder, and has a specific light transmittance characteristic in a predetermined wavelength region. Since the light is selectively transmitted by the multilayered light interference film and the chromaticity coordinates are defined so as to be located substantially on the locus of the black body, a lamp having blue light with good color rendering properties can be obtained.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a 150W according to the present invention.
FIG. 2 is a side view showing one embodiment of the metal halide lamp of FIG. In the figure, reference numeral 1 denotes a quartz arc tube in which at least main electrodes are sealed at both ends and iodides of dysprosium, neodymium and cesium, mercury and argon gas are sealed. A heat-resistant cylindrical body 2 is provided on the outer periphery of the arc tube 1,
A multilayer optical interference film 3 is provided on the inner and outer surfaces. The interference film 3 is composed of a ten-layer film in which five layers of TiO ₂ and SiO ₂ are alternately laminated, and a dip method using an organic metal compound solution as a material is used for the formation.

Here, the spectral transmittance characteristics of the multilayer optical interference film 3 are shown in FIG. As shown in FIG.
380 nm to 500 n in the visible light range of 780 nm to 780 nm
m or in the wavelength range from 380 nm to 520 nm,
It has a light transmittance characteristic of 50% or more, and 700 nm to 780
It has a light transmittance characteristic of 20% or less in a wavelength region of nm, and has a light transmittance characteristic of zero or less than 50% in other visible wavelength regions. The arc tube 1 and the cylindrical body 2 to which the optical multilayer interference film 3 is attached are held via an arc tube mount structure in an outer bead having a base 4 fixed to one end. In the figure, reference numeral 6 denotes a getter.

Next, an experimental example will be described. A 150 W metal halide lamp according to the present invention (Example 1), a 150 W metal halide lamp in which indium iodide, mercury, and a rare gas are sealed in an arc tube so as to emit blue light (Comparative Example 1); Is 6000K-70
A multi-layer optical interference film is formed on the surface of a heat-resistant cylinder and an arc tube containing dysprosium, neodymium, and cesium iodide, mercury, and a rare gas so that the average color rendering index is 95K or more at 00K. A prototype 150 W metal halide lamp (Comparative Example 2) was manufactured, and the spectral distribution of each lamp and its chromaticity coordinate points were measured.

FIG. 3 is a graph showing the spectral distribution characteristics of the lamp of the first embodiment.
Shown in 4 and 5 show spectral distribution characteristics of the lamps of Comparative Example 1 and Comparative Example 2. FIG. Note that the first embodiment shown in FIG.
Since the radiation intensity is lower than that of the other comparative examples, the vertical axis of the figure is enlarged. As is apparent from FIG. 3, the wavelength of 380 nm to 520 nm is obtained by the action of the multilayer optical interference film having a specific light transmittance characteristic in a predetermined wavelength range as compared with the comparative example lamp.
It is recognized that the light-emitting element has a spectral distribution characteristic mainly of light emission near m. Table 1 shows chromaticity coordinate points measured as these lamp characteristics.

[0012]

[Table 1]

FIG. 6 is a chromaticity coordinate diagram of Lampno of the first embodiment and comparative examples 1 and 2. As is clear from FIG.
The chromaticity coordinate point of the lamp of the first embodiment is substantially on the extension of the blackbody radiation locus, and soft blue light is obtained as the irradiation light. On the other hand, although the chromaticity coordinate point of the lamp of Comparative Example 1 is close to the extension line of the blackbody radiation locus, the illuminating light is dark blue, and the present invention shown in FIG. Are more effective. Further, the chromaticity coordinate point of the lamp of Comparative Example 2 is substantially on the extension line of the blackbody radiation locus, and white light effective for general store illumination can be obtained, but the blue light targeted by the present invention is not irradiated.

Further, curves A and B shown in FIG. 7 are provided on the inner and outer surfaces of the arc tube and the heat-resistant and heat-resistant cylinder filled with dysprosium, neodymium and cesium iodide, mercury and a rare gas.
A 150 W metal halide lamp on which a multilayer optical interference film having a spectral transmittance characteristic as shown in FIG.
4) was prototyped, and the chromaticity coordinate points of the lamp were measured in the same manner as described above. Table 2 shows the measurement results.

[0015]

[Table 2]

FIG. 8 is a chromaticity coordinate diagram of the lamps of Example 1, Comparative Examples 3 and 4. As is clear from FIG. 8, the chromaticity coordinate points of the lamp of Comparative Example 3 in which the multilayer optical interference film having the spectral transmittance characteristic shown by the curve A in FIG. The irradiation light is bluish-green in addition to being away from the trajectory extension line. Further, the lamp of Comparative Example 4 in which the multilayer optical interference film having the spectral transmittance characteristic shown by the curve B in FIG. 7 is applied has a transmittance of not less than 20% at a wavelength of 700 nm or more, and the irradiation light is close to purple, so that the color rendering properties are high. Has become a bad lamp.

[0017]

As described above with reference to the embodiments,
According to the present invention, a metal halide lamp having better color rendering properties and a blue emission color can be obtained. In addition to irradiating the irradiated object with blue light, the color rendering property around the irradiated object can also be improved, so that an effective color rendering property for show-up lighting and aquarium effect lighting in a store is provided. A blue color is obtained. Further, since it contains many wavelength components having a high transmittance of 450 to 550 nm in water, a metal halide lamp most suitable as an illumination light source for an aquarium can be obtained.

[Brief description of the drawings]

FIG. 1 is a side view showing one embodiment of a metal halide lamp according to the present invention.

FIG. 2 is a characteristic diagram showing a spectral transmittance of a multilayer optical interference film of one example according to the present invention.

FIG. 3 is a spectral distribution diagram of the metal halide lamp of Example 1 according to the present invention.

FIG. 4 is a spectral distribution diagram of the lamp of Comparative Example 1.

FIG. 5 is a spectral distribution diagram of the lamp of Comparative Example 2.

FIG. 6 shows Example 1 and Comparative Examples 1 and 2 according to the present invention.
3 is a chromaticity coordinate diagram of the lamp of FIG.

FIG. 7 is a characteristic diagram showing the spectral transmittance of the multilayer optical interference films of Comparative Examples 3 and 4.

FIG. 8 shows Example 1 and Comparative Examples 3 and 4 according to the present invention.
3 is a chromaticity coordinate diagram of the lamp of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Arc tube 2 Heat-resistant cylinder 3 Multilayer interference film 4 Cap 5 Outer bead 6 Getter

Claims (1)

[Claims] 1. The lamp has a color temperature of 6000K to 7000.
K, an arc tube enclosing at least dysprosium, neodymium, and cesium iodide, mercury, and a rare gas so that the average color rendering index is 95 or more; and a heat-resistant cylinder around the arc tube. Is arranged on the surface of the cylindrical body.
composed of a metal oxide of iO ₂ and SiO ₂ , and 380
50% in the wavelength region of nm to (510 ± 10 nm)
Forming a multilayer light interference film having the above light transmittance, light transmittance of 20% or less in a wavelength region of 700 nm to 780 nm, and light transmittance characteristics of 0 to 50% in a wavelength region of other visible light; The tube and the cylinder are held in the outer sphere, and the chromaticity coordinate is X = 0.215 to 0.
225, wherein Y = 0.18 to 0.22.