JPH1145683A - Lighting system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrict the change of a color temperature by dim lighting. SOLUTION: This device has a plurality of emission parts formed with rare gas and metal halide filled in emitting tubes 1a and a control part 2c to control input power to a plurality of emission parts. In this case, a plurality of emission parts contain first emission parts 1c in which a color temperature rises when the input power is reduced and second emission parts 2d in which a color temperature drops when the input power is reduced. Mercury is filled in the emitting tubes 1a for the first emission parts 1c and metal halide is filled in the emitting tubes 1a for the second emission parts 1d, including at least one of sodium or cesium halide and at least one of scandium, europium and lutetium halide.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting device,
In particular, the present invention relates to a lighting device including a plurality of light-emitting portions in which a rare gas and a metal halide are sealed in a space inside a light-emitting tube, and which can be controlled by a control portion.

[0002]

2. Description of the Related Art Metal halide lamps, in which a rare gas and a metal halide are sealed in the inner space of an arc tube, are used for a very wide range of applications because of their features of high brightness, high efficiency, and high color rendering. I have. However, dimming lighting in which the light output is freely changed without changing the color characteristics of the lamp in the lighting device using the lamp has not been realized for the following reasons.

In a general metal halide lamp, a rare gas (gas at normal temperature) for starting the lamp, mercury serving as a buffer gas for maintaining a lamp voltage, and a metal halide emitting a desired light emit light. It is enclosed in the arc tube which is a part.

[0004] The amount of light emitted from a metal halide depends on the vapor pressure of the metal. In addition, enclosed mercury (Hg)
As shown in FIG. 5, the vapor pressure characteristics of metals and metal halides (for example, NaI, CsI, etc.) are all different from each other, so that the evaporation amount of each metal is greatly affected by the change in the coldest point temperature. Therefore, the light emission amount is affected by the coldest point temperature. Therefore, in a metal halide lamp, a lamp design such as an enclosing ratio is performed in accordance with the coldest point temperature at the time of rated output to obtain a light emission balance that can obtain a desired light emission color.

[0005] In the metal halide lamp designed in this way, when the input power is increased or decreased, the coldest point temperature rises and falls accordingly, and the emission spectrum of each metal fluctuates as described above. Will collapse and the light color will change significantly. For example, in a lamp filled with argon, mercury, sodium iodide, and scandium iodide, the color temperature is 4000 K when the lamp is operated at the rated power of 250 W, and the emission spectrum at this time has the characteristics shown in FIG. When this lamp is operated at 175 W, which is 30% of the rated output, the color temperature is 5400.
K, and the emission spectrum at this time has the characteristics shown in FIG.

As described above, when the input power is decreased, the coldest point temperature is decreased, and the emission of sodium and scandium is greatly reduced. On the other hand, mercury does not weaken its light emission because its vapor pressure is high even if the coldest point temperature is slightly lowered, and its effect on light color is rather increased because its relative ratio to the metal halide is increased. Since mercury emits light mainly in the blue region, the radiated light from the lamp changes from white to bluish white, and a large change in the light color occurs as in the values described above.

As described above, in a lighting device using a conventional metal halide lamp, if the input power of the metal halide lamp is changed, the light color changes. Therefore, it is impossible to perform light control with a constant light color. Met.

[0008] As a metal halide lamp in which this disadvantage is improved, there is, for example, a lamp disclosed in JP-A-6-84496. This metal halide lamp is characterized in that a metal halide and a rare gas are filled as filling substances. Since mercury is not sealed, it is said that by lowering the input power, even if the coldest point temperature decreases, the emission spectrum balance is small and the change in emission color can be suppressed low. In the lamp shown in the example, the color temperature changes by 400 K at a dimming ratio of 50%.

Although it is not a classification for metal halide lamps, there are three types of light source colors for fluorescent lamps: bulb color, warm white, white, day white, and daylight color (JIS Z 9112). Although this division method is not strictly determined to match the light color sense perceived by humans, it is generally used in the lighting industry and is considered to be one of the criteria for determining color change. Considering this criterion, the change in the color temperature in the above embodiment is 3700K.
From 4100K to warm white to white. This color change width is an amount by which the difference in color can be sufficiently sensed by human senses, and although it is more effective than a lamp in which mercury is sealed, it is considered that its dimming performance is not sufficient.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide an illumination using a metal halide lamp in which a rare gas and a metal halide are sealed in an arc tube. It is an object of the present invention to provide an illumination device in which the amount of light emission can be varied without substantially changing the light color, that is, the change in color temperature due to dimming lighting is suppressed.

[0011]

According to the present invention, in order to solve the above-mentioned problems, according to the first aspect of the present invention, there are provided a plurality of light emitting portions each having a rare gas and a metal halide sealed in an arc tube. A lighting device comprising: a control unit that controls input power to the plurality of light-emitting units; wherein the plurality of light-emitting units include a first light-emitting unit whose color temperature increases when input power is reduced; Color temperature decreases when power is reduced.
And a light-emitting unit.

According to the second aspect of the present invention, the first aspect is provided.
The lighting device according to claim 1, wherein mercury is sealed only in the arc tube of the first light emitting unit of the first and second light emitting units, and metal halide sealed in the arc tube of the second light emitting unit. Wherein the halide is at least one of sodium or celsium halide and at least one of scandium, europium or lutesium halide.

[0013]

1 to 3 show a first embodiment of a lighting device according to the present invention. As shown in the schematic diagram of FIG. 1, the lighting device has a plurality of lighting devices. It is configured to include two lamps 1, a lighting device 2, and a device 3.

Each of the two lamps 1 has an arc tube 1a formed of a translucent material such as quartz glass, and is formed so as to secure a closed space with a translucent material such as quartz glass or hard glass. It is configured to be housed in the outer tube 1b. The two lamps 1 are metal halide lamps in which at least a metal halide and a rare gas are sealed inside an arc tube 1a. The first light emitting unit 1c has a higher temperature, and the other light emitting unit 1d has a lower color temperature when the input power is reduced. The arc tube 1
A vacuum or low-pressure gas is sealed in the closed space between the light emitting tube 1a and the outer tube 1b. During the operation of the lamp, the outside air and the light emitting tube 1a are substantially thermally insulated from each other, and the light emitting tube 1a is cooled. Are being restricted.

When the input power is reduced, the color temperature rises. Inside the arc tube 1a, which is the first light emitting portion 1c of one of the lamps 1 (lamp A), for example, 16 mg of a metal halide as a light emitting substance is provided. Of sodium iodide and 4 mg of scandium iodide, argon as a rare gas, and a predetermined amount of mercury as a buffer gas. Table 1 shows the measurement results of the color temperature change when one of the lamps 1 (Lamp A) configured as described above is illuminated by changing the input power. The total luminous flux is 52% of the total luminous flux at the time of input of 250 W. When the input power is reduced from 250 W to 175 W, the color temperature increases by about 800 K.

When the input power is reduced, the color temperature is lowered. Inside the arc tube 1a as the second light emitting portion 1d of the other lamp 1 (lamp B), for example, 16 mg of a metal halide as a light emitting substance is provided. Of sodium iodide, 4 mg of scandium iodide, and 200 Torr of xenon as a rare gas. That is, mercury is not sealed inside the arc tube 1a of the second light emitting section 1d. Table 1 shows the measurement results of the color temperature change when the lamp 1 (Lamp B) configured as described above is dimmed and turned on while changing the input power. The total luminous flux of the lamp 1 at the time of 175 W input is shown in Table 1. Is 32% of the total luminous flux when the input power is 250 W, and when the input power is reduced from 250 W to 175 W, the color temperature becomes about 8%.
Decrease by 00K or more.

The lighting device 2 includes lighting circuits 2a and 2b for lighting two lamps 1 of a lamp A and a lamp B;
The control unit 2c is configured so that the two lamps 1 can be lit and lit by the control unit 2c. The appliance 3 has one of the lamps 1 having the first light emitting portion 1c whose color temperature increases when the input power is reduced.
In addition, two types of lamps 1 having the second light emitting portion 1d whose color temperature is reduced when the input power is reduced are mounted.

The two lamps 1 (Lamp A + Lamp B) of the lighting device thus constructed are changed from 250 W to 175 W.
When the color temperature change was measured by changing the input power to each lamp 1, the color temperature change width from 250 W to 175 W could be suppressed to 110 K as shown in Table 1.
FIG. 2 shows an emission spectrum when the input power is 250 W, and FIG. 3 shows an emission spectrum when the input power is 175 W.

[0019]

[Table 1]

With such a configuration, in the lighting device according to the present embodiment, the first light emitting portion 1c and the second light emitting portion 1d, which are the light emitting portions of the two lamps 1, are provided.
When the lighting is performed by controlling the control unit 2c to reduce the input power, that is, when the dimming lighting is performed so as to reduce the light output, the one lamp 1 having the first light emitting unit 1c in which mercury is sealed becomes The color temperature increases, and the color temperature of the other lamp 1 having the second light emitting portion 1d decreases, thereby canceling each other's change in color temperature. For this reason, the amount of light emission can be varied by changing the input power without substantially changing the light color, that is, the change in color temperature due to dimming lighting can be greatly suppressed, and therefore, the light color hardly changes. Practical dimming lighting becomes possible.

The lighting device according to the second embodiment of the present invention also includes:
Schematically, it has the same configuration as that of the first embodiment, and the difference from the first embodiment is that the second light emitting unit 1d
And the other lamp 1 (lamp C) is enclosed in the arc tube 1a, and the other components are configured in the same manner as in the first embodiment.

The filling of the other lamp 1 (lamp C) constituting the second light emitting portion 1d inside the light emitting tube 1a is, for example, 16 mg of sodium iodide and 4 mg of iodine as a metal halide as a light emitting substance. For example, xenon of 200 Torr is sealed as lutetium fluoride and a rare gas. Table 2 shows a change in color temperature when the other lamp 1 (lamp C) is turned on while changing the input power from 250 W to 175 W.
Shown in The first light emitting section 1c uses one of the lamps 1 (lamp A) in the first embodiment.
When the two lamps 1 (lamp A + lamp C) of the illuminating device thus configured are measured by changing the input power to each lamp 1 from 250 W to 175 W, the change in color temperature is obtained.
As shown in Table 2, the color temperature change width from 250 W to 175 W could be suppressed to 169 K. Even with this configuration, substantially the same effects as in the first embodiment can be obtained.

[0023]

[Table 2]

The third embodiment of the lighting device of the present invention also
Schematically, it has the same configuration as that of the first embodiment, and the difference from the first embodiment is that the second light emitting unit 1d
Are enclosed in the arc tube 1a of the other lamp 1 (lamp D), and the other components are configured in the same manner as in the first embodiment.

The sealed substance inside the arc tube 1a of the other lamp 1 (lamp D) constituting the second light emitting portion 1d is, for example, 16 mg of sodium iodide and 4 mg of iodine as a metal halide as a light emitting substance. And 200 Torr of xenon as a rare gas are enclosed. Table 3 shows a change in color temperature when the other lamp 1 (lamp D) is turned on while changing the input power from 250 W to 175 W. The first light emitting section 1c uses one of the lamps 1 (lamp A) in the first embodiment. When the two lamps 1 (lamp A + lamp D) of the lighting device thus configured are measured for color temperature change by changing the input power to each lamp 1 from 250 W to 175 W, as shown in Table 3, 250 W is obtained as shown in Table 3. From 175W to 187K. Even with this configuration, substantially the same effects as in the first embodiment can be obtained.

[0026]

[Table 3]

The fourth embodiment of the lighting device of the present invention also
Schematically, it has the same configuration as that of the first embodiment, and the difference from the first embodiment is that the second light emitting unit 1d
Are enclosed in the arc tube 1a of the other lamp 1 (lamp E), and the other components are configured in the same manner as in the first embodiment.

The filling of the other lamp 1 (lamp E) constituting the second light emitting portion 1d inside the light emitting tube 1a is, for example, 16 mg of cesium iodide and 4 mg of iodine as a metal halide as a light emitting substance. For example, xenon of 200 Torr is sealed as scandium halide and a rare gas. Table 4 shows the change in color temperature when the other lamp 1 (Lamp E) is turned on with the input power changed from 250 W to 175 W.
Shown in The first light emitting section 1c uses one of the lamps 1 (lamp A) in the first embodiment.
When the two lamps 1 (lamp A + lamp E) of the lighting device thus configured are measured by changing the input power to each lamp 1 from 250 W to 175 W,
As shown in Table 4, the color temperature change width from 250 W to 175 W could be suppressed to 194K. Even with this configuration, substantially the same effects as in the first embodiment can be obtained.

[0029]

[Table 4]

The inventor of the present application has proposed a lamp in which europium iodide or lutetium iodide is used instead of scandium iodide as the filling of the other lamp 1 (lamp E) in the arc tube 1a in the present embodiment. Prototype one lamp 1
As a result of measuring the same color temperature change in combination with (Lamp A), it was confirmed that substantially the same effect as in the present embodiment was obtained.

In each of the above-described embodiments, the metal halide or rare gas sealed inside the arc tube 1a has been described with specific examples including the amount of the metal halide. The types of the rare gas and the rare gas, and the amount of the noble gas are not limited to those illustrated. Further, in each of the above embodiments, the lamp 1 has two lamps, that is, the lamp 1 having the first light emitting portion 1c and the lamp 1 having the second light emitting portion 1d. Not only
For example, as shown in FIG. 4, a lamp in which a first light-emitting unit and a second light-emitting unit are provided in one outer tube may be used. Any number of two or more lamps may be used as long as they include a combination of the unit and the second light emitting unit. Further, the same effect can be naturally obtained even if the above-mentioned lamp is an electrodeless metal halide lamp having no electrode in the arc tube.

[0032]

As described above, according to the present invention, when the light emitting unit is controlled by the control unit to perform dimming lighting, that is, the input power to the light emitting unit is reduced to reduce the amount of light emission. When lit, the color temperature of the first light-emitting unit increases, and the color temperature of the second light-emitting unit decreases, thereby canceling each other's change in color temperature. Therefore, the amount of light emission can be varied by changing the input power without substantially changing the light color, and the change in the color temperature due to dimming lighting can be greatly suppressed. Dimmable lighting is possible.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a lighting device according to a first embodiment of the present invention.

FIG. 2 shows an emission spectrum diagram of the above, when the input power is 250 W.

FIG. 3 is an emission spectrum diagram of the above, when the input power is 175 W;

FIG. 4 is a schematic diagram showing a different example of the lamp.

FIG. 5 is a vapor pressure characteristic diagram of a luminescent material used for a metal halide lamp.

FIG. 6 shows an emission spectrum diagram of a conventional metal halide lamp in which mercury is sealed, in which the input power is 250 W
It is the time.

FIG. 7 shows an emission spectrum diagram of the above, when the input power is 175W.

[Explanation of symbols]

 1a Arc tube 1c First light emitting unit 1d Second light emitting unit 2c Control unit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takuma Hashimoto 1048 Odakadoma, Kadoma, Osaka Prefecture Inside Matsushita Electric Works, Ltd.

Claims (2)

[Claims] 1. A lighting device comprising: a plurality of light-emitting portions in which a rare gas and a metal halide are sealed in an arc tube; and a control portion for controlling input power to the plurality of light-emitting portions. The plurality of light emitting units include a first light emitting unit whose color temperature increases when input power is reduced, and a second light emitting unit whose color temperature decreases when input power is reduced. Lighting equipment. 2. A metal halide sealed inside the arc tube of the second light emitting portion while mercury is sealed only inside the arc tube of the first light emitting portion of the first and second light emitting portions. 2. The lighting device according to claim 1, wherein at least one of sodium or celsium halide and at least one of scandium, europium or lutesium halide is used. 3.