JPH0765793A - Metal halide lamp and lighting system - Google Patents

Abstract

PURPOSE:To obtain a metal halide lamp and a lighting system in which the luminous efficiency is increased and the color temperature is reduced by using sodium, and a special color rendering evaluation number to evaluate the regeneration of the red color is increased without reducing the mean color rendering evaluation number. CONSTITUTION:In a luminous tube 2 an electrode 4 is sealed, at least sodium, a metal halide having the maximum visibility of luminous scope near 555nm, mercury, and a rare gas are sealed. In such a metal halide lamp, a means to regulate the transmission of the light of about 580 to 590nm, of the light discharged from the luminous tube 2, is provided. As a result, since the light of a yellow or an orange color of the visible rays discharged from the luminous tube 2 is suppressed, a special color rendering evaluation number R9 to evaluate the regeneration of the red color is increased, and the mean color rendering evaluation number Ra is also increased. Consequently, the regeration of the red color system is improved, and the merchandise lighting is made effective.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal halide lamp and a lighting device adapted to reflect light emitted from the metal halide lamp by a reflector.

[0002]

2. Description of the Related Art Recently, a small metal halide lamp is used as a light source for store lighting, the small metal halide lamp is housed in a reflector, and the reflector is installed on a low ceiling surface of a store or the like and emitted from the metal halide lamp. BACKGROUND An illuminating device, such as a downlight, that reflects light with a reflector and illuminates a product with this light is used.

Since metal halide lamps have high luminous efficiency, low color temperature, and excellent color rendering properties, they are widely used in various fields. Especially, metal halide lamps using sodium halide as a light emitting metal. In this case, sodium has an emission wavelength of 589 nm and contributes to the above-mentioned various properties, and when used for store lighting, the color reproducibility of the product is excellent, and thus its use is expanding.

For example, in our 150 W type metal halide lamp in which Sn-Na-Tl-In-Li-based halide is enclosed, the luminous efficiency is 80 lm / W, the color temperature Tc is 3000 K, and the average color rendering index Ra is 80. It exhibits a high lamp characteristic.

[0005]

However, with the spread of the metal halide lamps of this type, further improvement of the color rendering properties is desired. Especially when illuminating products in shops such as butcher shops, fresh fish shops, fruits, vegetables, and ikebana, the above-mentioned conventional metal halide lamps have a special color rendering index R9 of -20 to -50 for evaluating the appearance of red. However, it has been evaluated that the appearance of red is not sufficient, and there is a demand for the development of a metal halide lamp that vividly reproduces the colors of meat, fresh fish, fruits, vegetables, and ikebana.

The reason for the poor red reproducibility is presumed to be that the reddish emission color becomes inconspicuous due to the strong yellow or orange emission color around 589 nm of sodium. Therefore, it is possible to avoid using sodium that emits yellow to orange light, but the presence of sodium is indispensable for increasing the luminous efficiency and improving the color rendering of this type of metal halide lamp. , It cannot be removed.

The present invention has been made in view of the above circumstances. An object of the present invention is to evaluate the reproducibility of red color by using sodium to increase the luminous efficiency and lower the color temperature. An object of the present invention is to provide a metal halide lamp and a lighting device in which the color rendering index R9 is increased and the average color rendering index Ra is further improved.

[0008]

According to a first aspect of the present invention, at least sodium, a metal halide having a light emitting region near 555 nm, mercury, and a rare gas are enclosed in an arc tube made of quartz glass with electrodes sealed therein. The metal halide lamp described above is characterized in that it is provided with a means for restricting the transmission of light around 580 to 590 nm of the light emitted from the arc tube.

The invention of claim 2 is characterized in that the metal halide having an emission region near 555 nm is a halide of thallium. The invention of claim 3 is the above-mentioned 58.
The means for restricting the transmission of light in the vicinity of 0 to 590 nm is characterized in that a filter film for restricting the transmission of light in the vicinity of 580 to 590 nm is formed on the inner surface or the outer surface of the arc tube.

According to a fourth aspect of the present invention, in the case of a double-tube lamp in which an arc tube is housed in an outer tube, the outer tube is provided with the above-mentioned 580-5.
It is characterized in that a means for restricting the transmission of light near 90 nm is provided.

According to a fifth aspect of the present invention, the outer pipe is 580-
It is characterized by being formed of neodymium glass that reduces the transmission of light near 590 nm. According to the invention of claim 6, in the case of a double-tube lamp in which an arc tube is housed in an outer tube, a transmissive envelope which surrounds the arc tube is provided in the outer tube, and the envelope includes a light-transmissive envelope near 580 to 590 nm. It is characterized in that means for preventing permeation is provided.

According to a seventh aspect of the present invention, an envelope body is 580-5.
It is characterized by being formed of neodymium glass that reduces the transmission of light near 90 nm. The invention of claim 8 houses a metal halide lamp in which at least sodium, a metal halide having a light emitting region near 555 nm, mercury and a rare gas are sealed in an arc tube made of quartz glass with electrodes sealed therein, and this lamp is housed. And a reflector for reflecting the light emitted from this lamp, and means for controlling the irradiation of light in the vicinity of 580 to 590 nm of the light reflected by the reflector and irradiated forward. Is provided.

The invention of claim 9 is based on the above-mentioned 580 to 590 nm.
A means for controlling the irradiation of light in the vicinity is provided on the front surface of the reflector.
It is characterized in that a front glass for controlling the transmission of light in the vicinity of 0 to 590 nm is provided.

[0014]

According to the present invention, in any of the claims,
580-590nm of visible light emitted from arc tube
Since a means for restricting the irradiation of light in the vicinity is provided, the emission of yellow or orange color in the vicinity is suppressed, so that the special color rendering index R9 for evaluating the reproducibility of red becomes high, and at the same time, the overall color rendering And the average color rendering index Ra also improves. Moreover, since sodium is used, the luminous efficiency is high and the color temperature can be kept low. For this reason, the red-based reproducibility is improved, which is effective for illuminating products and the like.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on a first embodiment applied to a downlight type lighting device used for shop lighting or the like shown in FIGS. In FIG. 1, reference numeral 1 denotes a small-sized metal halide lamp used as a light source and having a single sealed structure.
w, and a crushed sealing portion 3 is formed at one end of an arc tube 2 made of substantially spherical quartz glass having an inner diameter of 12.0 mm, and the sealing portion 3 is sealed with a pair of electrodes 4, 4. . Electrode 4,
Reference numeral 4 denotes an electrode shaft 5 made of tungsten, and electrode coils 6, 6 made of tungsten wire wound around the tips of the electrode shafts 5, 5 respectively. They are facing each other at a distance. The electrode shafts 5 and 5 are connected to metal foil conductors 7 and 7 made of molybdenum sealed in the crushing and sealing portion 3, and external lead wires 8 and 8 are connected to the metal foil conductors 7 and 7. ing. The external lead wires 8 and 8 are led out from the end surface of the crushable sealing portion 3.

In such an arc tube 2, Sn-Na-Tl-In-Li iodide and bromide are filled as a light emitting metal, and mercury as a buffer metal and argon gas as a rare gas are filled. There is.

The single-sealed metal halide lamp 1 having such a structure is housed in the envelope 10. Envelope 10
Is composed of a reflector 12, a front glass 15 that hermetically closes the front opening of the reflector 12, and a base 18 attached to the back surface of the reflector 12.

The reflector 12 is made of, for example, quartz glass,
Effective reflection part 21 consisting of a rotation curve and this effective reflection part 21
Is provided with a concave portion 22 which is continuous with the closed portion 23. The inner portion of the concave portion 22 is closed by a closing wall 23. On the inner surfaces of the effective reflection portion 21 and the concave portion 22, a reflection film 25 made of an aluminum vapor deposition film or the like is formed.

Support wires 26, 26 also serving as a pair of conductive wires are hermetically penetrated through the closed wall 23 of the reflector 12, and the ends of the support wires 26, 26 extending inside the reflector 12 are provided. The external lead wires 8 of the metal halide lamp 1 are joined to each other. Therefore, the metal halide lamp 1 has a support wire 2
6, 26, mechanically supported, in this case the lamp 1
Is arranged so that the light emission center of is coincident with or close to the focal position of the effective reflection portion 21. Further, the metal halide lamp 1 is electrically connected to the support wires 26, 26.

Support wires 26, 26 are connecting wires 27,
It is connected to the shell 18 a of the base 18 and the external terminal 18 b via 27. The envelope 10 is filled with an inert gas.

In the downlight illuminator having such a structure, a part of the light emitted from the metal halide lamp 1 directly passes through the front glass 15, and the rest of the light is a reflection film 25 formed on the inner surface of the reflector 12. Is reflected by the front glass 15 toward the front glass 15 and transmitted through the front glass 15 to illuminate the front (downward).

By the way, in the conventional case, the front glass 15 was made of hard glass, but the front glass 15 of the present invention has a means for restricting the transmission of light in the vicinity of 580 to 590 nm, for example, 580. Although a filter film for controlling the transmission of light in the vicinity of ˜590 nm may be formed, in this embodiment, neodymium glass containing neodymium oxide is used as the front glass 15. Neodymium glass reduces the transmission of light near 580 to 590 nm by about 30%.

The average color rendering index Ra, the color temperature Tc, the special color rendering index R9, and the lamp efficiency of the light transmitted through the front glass 15 were measured in the conventional case and the present example, and the results are shown in Table 1. The measured value was obtained.

[0024]

[Table 1]

As is clear from Table 1, in the case of this embodiment, the respective characteristics of the average color rendering index Ra, color temperature Tc and special color rendering index R9 are greatly improved as compared with the conventional one, and particularly The color rendering index R9 reaches 60 points,
The appearance of red color has been significantly improved. In exchange for this, the reduction in lamp efficiency could be limited to about 15%.

The reason for this is that the front glass 15 made of neodymium glass regulates the transmission of light in the vicinity of 580 to 590 nm. That is, FIG. 2 shows the spectral distribution characteristics of the conventional lighting device in which the front glass 15 is made of hard glass, while the spectral distribution characteristics of the lighting device of the present embodiment using the front glass 15 made of neodymium glass are shown in FIG. 3 shows. As can be understood by comparing these spectral distribution characteristics, the spectral distribution characteristics of this embodiment are 580 to 590.
The emission intensity near nm is low. From this fact, the special color rendering index R9 is greatly improved from the conventional -27 point to +60 point, and the average color rendering index Ra and the color temperature Tc are improved in association with this.

Here, the reason for blocking the spectrum of 580 to 590 nm is as follows. That is, this type of metal halide lamp originally uses the emission wavelengths of sodium Na and thallium Tl in order to improve the average color rendering index Ra, color temperature Tc, and lamp efficiency. The emission wavelength of Natrim Na has a main peak at 589 nm (yellow to orange emission color), which enhances the average color rendering and the emission efficiency.

The emission wavelength of thallium Tl is 535.
It has a main peak in the vicinity of nm, which is close to the maximum visibility of 555 nm (greenish emission color). Therefore, by using Thallium Tl, the emission in the maximum visibility of 555 nm is secured and high brightness is obtained. This is because of the reason.

Therefore, in this type of metal halide lamp, it is indispensable to enclose sodium Na and thallium Tl. However, when Natrim Na is used, as can be understood from the spectral distribution characteristics of FIG. 2, the emission intensity in the vicinity of 589 nm (yellow or orange emission color) is too strong, so that this yellow or orange emission is red. Was a cause of hindering the reproducibility of. In other words, in the conventional case, since the focus was on increasing the lamp efficiency,
The red-based special color rendering index R9 tends to be sacrificed.

Therefore, in the present invention, the emission intensity of the yellow to orange emission color is suppressed so that the emission intensity of the entire visible light is flattened, the red special color rendering index R9 is increased, and the average value is increased. The color rendering index Ra is also increased.

For this reason, in the case of the present embodiment using neodymium glass containing neodymium oxide as the front glass 15 as described above, the neodymium glass is 5
Since the transmission of light around 80 to 590 nm is reduced to about 30%, the emission intensity around 589 nm (yellow or orange luminescent color) is suppressed as described above, and the average color rendering index as shown in Table 1 Ra and the color temperature Tc can be improved, and the red-based special color rendering index R9 can be significantly improved. In this case, since the emission intensity of yellow or orange is suppressed, there is concern that the lamp efficiency will decrease, but the light around 580 to 590 nm is cut by about 70%. The reduction in efficiency can be minimized.

The present invention is not limited to the illuminating device composed of the single-sealed metal halide lamp 1 and the envelope 10 as described above. That is, FIG. 4 shows a second embodiment of the present invention. In the figure, reference numeral 50 is a reflector having a curved surface, 51 is a front glass attached to the front opening of the reflector 50, and 52 is a reflector. It is a socket attached to the back surface of 50. The reflector 50 accommodates a double-tube metal halide lamp 55 using the T-shaped outer tube 30. In this metal halide lamp 55, a base 35 is attached to one end of a T-shaped outer tube 30, and an arc tube 31 is housed in the outer tube 30. The arc tube 31 has electrodes 32, 32 sealed at both ends. The arc tube 31 is filled with iodide and bromide of Sn—Na—Tl—In—Li as a light emitting metal, and with mercury as a buffer metal and argon gas as a rare gas.

The metal halide lamp 55 as described above is attached to the reflector 50 by screwing the base 35 attached to one end into the socket 52 provided on the back surface of the reflector 50, and the emission center of the metal halide lamp 55 is the reflector 50. It is located at or near the focal point. Therefore, the light emitted from the metal halide lamp 55 is reflected by the reflecting surface of the reflector 50, passes through the front glass 51, and is projected forward.

In the illuminating device having such a structure, when neodymium glass containing neodymium oxide is used for the front glass 51, the neodymium glass is 580 to 590 nm.
Since the transmission of light in the vicinity is regulated, similar to the above embodiment,
It is possible to suppress the emission intensity near 589 nm (yellow or orange color), improve the average color rendering index Ra and the color temperature Tc, and significantly improve the red color rendering index R9.

In the case of the first and second embodiments, 580 to 590 nm of the light emitted from the illumination device is used.
The front glass 1 is a means for controlling the transmission of light in the vicinity.
Although the example in which neodymium glass is used for 5 or 51 has been described, the present invention is not limited to this.

For example, instead of using the neodymium glass as the front glass 15 or 51, a filter film for restricting the transmission of light in the vicinity of 580 to 590 nm may be formed on the outer or inner surface of the conventional hard glass. As this type of optical interference film, a multilayer selective absorption film is known in which a large number of high-refractive-index metal oxides and low-refractive-index metal oxide films are alternately laminated. Can be used.

Further, instead of forming a filter film for restricting the transmission of light in the vicinity of 580 to 590 nm on the outer or inner surface of the front glass 15 or 51, the reflector 12 or 50
As a reflective film formed on the inner surface of the 580-59 nm by absorbing or transmitting light in the vicinity of 580-590 nm
However, a reflection film composed of a selective absorption film that regulates reflection of light near 0 nm but reflects light of other wavelengths may be used.

Furthermore, on the inner or outer surface of the outer tube 30 of the metal halide lamp 1 or 55 and the arc tubes 2 and 31,
You may form the filter film which controls transmission of the light of 580-590 nm vicinity.

As described above, the illuminating device in which the filter film for restricting the reflection and transmission of the light in the vicinity of 580 to 590 nm is used in the parts other than the front glass 15, 51 is a reflector not using the front glass 15. Can also be implemented.

Furthermore, the present invention provides a reflector 1 as described above.
The present invention can be applied not only to the metal halide lamp that constitutes the lighting device in combination with 2, 50, but also to the lamp itself.

That is, FIG. 5 illustrates, as a third embodiment of the present invention, a double-tube type metal halide lamp using a T-shaped outer tube 30 similar to the second embodiment. In the figure, reference numeral 31 designates a bulb sealed at both ends, and electrodes 32, 32 are sealed so as to face a bulb made of quartz glass, and the bulb 31 is made of Sn-Na- as a luminescent metal.
In addition to encapsulating Tl-In-Li iodide and bromide, mercury is enclosed as a buffer metal and argon gas is enclosed as a rare gas. This arc tube 31 has lead wires 33, 33 connected to the electrodes 32, 32 connected to support wires 34, 34, whereby the arc tube 3
1 is mechanically supported in the outer tube 30 and is electrically connected to a base 35 through support wires 34, 34.

In the outer tube 30, as a transparent enclosure,
An intermediate tube 36 is housed. The intermediate tube 36 is composed of a glass tube which is open at both ends and surrounds the arc tube 31, and is supported by a support wire 34 via holders 37.

In the case of this embodiment, 580 to 59
Means for restricting the transmission of light near 0 nm is provided in the intermediate tube 36. That is, in this example, the intermediate tube 36 is made of glass containing neodymium oxide.

In such a structure, when the light emitted from the arc tube 31 passes through the intermediate tube 36, 58
Since the transmission of light in the vicinity of 0 to 590 nm is regulated, the special color rendering index R9 is increased and the average color rendering index Ra is also improved, as in the illumination device of FIG. Moreover, the color temperature can be kept low and the luminous efficiency can be kept high.

In the case of such a triple-tube structure, instead of forming the intermediate tube 36 with neodymium glass, the inner or outer surface of the intermediate tube 36 is made to transmit the light around 580 to 590 nm as described above. A restricting filter film may be formed.

Furthermore, the present invention can be applied to a metal halide lamp having a single-sealed double tube structure shown in FIG. In this embodiment, the single-sealed arc tube 2 shown in FIG. 1 is used.
Is housed in a single-sealed outer tube 40 to form a double tube structure. The structure of the arc tube 2 is the same as that in FIG. 1 and its description is omitted. The outer tube 40 has a crushed seal portion 4 at one end.
1 and the metal foil conductors 42, 42 made of molybdenum are sealed in the sealing portion 41. The outer lead wires 8 of the arc tube 2 housed in the outer tube 40 are the metal foil conductors 4 described above.
2, 42 are connected. And these metal foil conductors 4
External power supply lines 43, 43 are connected to 2, 42.

Also in this case, the arc tube 2 is filled with Sn-Na-Tl-In-Li iodide and bromide as the light emitting metal, and mercury as the buffer metal and argon gas as the noble gas. Is enclosed.

In the double-tube metal halide lamp having such a structure, if the outer tube 40 is made of neodymium glass, when the light emitted from the arc tube 2 passes through the outer tube 40, the wavelength of 580 to 590 nm is around. Since the transmission of light is regulated, the special color rendering index R9 is increased and the average color rendering index Ra is also improved, as in the illumination device of FIG. Moreover, the color temperature can be kept low and the luminous efficiency can be kept high.

Instead of the outer tube 40 made of neodymium glass, a filter film for restricting the transmission of light in the vicinity of 580 to 590 nm is formed on the inner surface or the outer surface of the outer tube 40 as indicated by reference numeral 45. May be.

Furthermore, the metal halide lamp of the present invention is not limited to a structure in which it is surrounded by an outer tube or an envelope, but there is also a type in which the arc tube is exposed and used for lighting. In the case of such a structure, the inner or outer surface of the arc tube is 580 to 590 nm.
A filter film that regulates the transmission of light in the vicinity may be formed.

Further, the metal halide lamp of the present invention is
It is not limited to encapsulating a Sn-Na-Tl-In-Li halide as a luminescent metal, but Dy-Ho-Tm-
It may be a metal halide lamp in which a halide of Na-Tl is enclosed, and in short, it is applicable to a metal halide lamp in which the emission wavelengths of those in which a halide of sodium Na and thallium Tl is enclosed are utilized.

[0052]

As described above, according to the present invention, the emission of light in the vicinity of 580 to 590 nm of the visible light emitted from the arc tube is restricted, so that yellow or orange light emission in the vicinity is suppressed. As a result, the special color rendering index R9 for evaluating the red color reproducibility becomes high, and at the same time the overall color rendering balance is improved, so that the average color rendering index Ra becomes high. Moreover, since sodium and thallium are used, the luminous efficiency is high and the color temperature can be kept low. As a result, the reddish reproducibility is improved, and the fresh food is effective as a light source for illumination of products with high color fashion.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a lighting device using a metal halide lamp as a light source according to a first embodiment of the present invention.

FIG. 2 is a spectral distribution characteristic diagram of a conventional lighting device.

FIG. 3 is a spectral distribution characteristic diagram of the illumination device of the present invention.

FIG. 4 is a sectional view of an illuminating device using a metal halide lamp as a light source, showing a second embodiment of the present invention.

FIG. 5 is a configuration diagram of a double-tube type metal halide lamp showing a third embodiment of the present invention.

FIG. 6 is a cross-sectional view of a metal halide lamp having a single-sealed double-tube structure according to a fourth embodiment of the present invention.

[Explanation of symbols]

1,55 ... Metal halide lamp 2,31
... Arc tube 3 ... Sealing part 4, 32 ... Electrode 10 ... Envelope 15 ... Front glass 18, 35 ... Base 21 ... Reflecting part 25 ... Reflecting surface 30 ... Outer tube 36 ... Intermediate tube (transparent enclosure) 4
5 ... Filter membrane

Claims (9)

[Claims] 1. A metal halide lamp in which at least sodium, a metal halide having an emission region near 555 nm, mercury, and a rare gas are enclosed in an arc tube made of quartz glass with an electrode sealed, and emitted from the arc tube. A metal halide lamp characterized by being provided with a means for restricting the transmission of light in the vicinity of 580 to 590 nm of the light emitted. 2. The metal halide lamp according to claim 1, wherein the metal halide having an emission region near 555 nm is a thallium halide. 3. The means for controlling the transmission of light in the vicinity of 580 to 590 nm is 580 to 5 on the inner surface or the outer surface of the arc tube.
The metal halide lamp according to claim 1 or 2, wherein a filter film is formed to control the transmission of light near 90 nm. 4. A double-tube lamp in which an arc tube is housed in an outer tube, the outer tube is provided with means for restricting transmission of light in the vicinity of 580 to 590 nm.
Alternatively, the metal halide lamp according to claim 2. 5. The metal halide lamp according to claim 4, wherein the outer bulb is made of neodymium glass that reduces the transmission of light near 580 to 590 nm. 6. In the case of a double-tube lamp in which an arc tube is housed in an outer tube, a transmissive envelope which surrounds the arc tube is provided in the outer tube, and the envelope is configured to transmit light in the vicinity of 580 to 590 nm. The metal halide lamp according to claim 1, further comprising a blocking means. 7. The metal halide lamp according to claim 6, wherein the enclosure is made of neodymium glass that reduces transmission of light near 580 to 590 nm. 8. A metal halide lamp in which at least sodium, a metal halide having a light emitting region near 555 nm, mercury and a rare gas are enclosed in an arc tube made of quartz glass with electrodes sealed therein, and the lamp is housed. A lighting device including a reflector that reflects the light emitted from the lamp, provided with means for restricting the irradiation of light in the vicinity of 580 to 590 nm of the light that is reflected by the reflector and is irradiated forward. A lighting device characterized by the above. 9. The means for controlling the irradiation of light in the vicinity of 580 to 590 nm is provided with a front glass for restricting the transmission of light in the vicinity of 580 to 590 nm on the front surface of the reflector. Illumination device described.