JP2001160377A - Tungsten halogen lamp, headlight for automobiles, and illuminator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tungsten halogen lamp, and a headlight for automobiles and an illuminator using the tungsten halogen lamp, in which blue color is enhanced and white light with high color temperature is generated, and in which total light flux equivalent to the conventional tungsten halogen lamp whose color temperature is low, in spite of having a color filter of pigment. SOLUTION: A filament 2 is positioned approximately on the central axis of a translucent airtight container 1 in which halogen and inert gas are enclosed, and on the surface of the translucent airtight container 1, an infrared reflecting interference membrane 5 for which the transmittance of visible light is controlled to an average of 80% or more for the wavelength of 550 nm or shorter and an average of 40% or shorter for longer than 550 nm. Preferably, the infrared light reflex interference membrane 5 is controlled to an average of 85% or more at the wavelength of 540 nm or shorter and 40-80% for the range of more than 540 nm to 560 nm. There is less color shift in the translucent airtight container 1, because the temperature of the filament 2 is uniformized by using quasi rotational ellipsoid or a rotational ellipsoidal shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a halogen bulb having a high color temperature, and a headlight and a lighting device for an automobile using the same.

[0002]

2. Description of the Related Art Halogen bulbs are generally used as light sources for automobile headlights.

[0003] Halogen bulbs used in automobile headlights include those with an infrared reflective film and those without. The former has a color temperature of 3320K, while the latter has a color temperature of 3250K, and the former has slightly more whitish light, but both basically belong to the so-called bulb color category due to the incandescence of tungsten.

However, when the illumination light of the headlight is white light, the visibility is good, so that a color filter film made of a pigment is applied to the outer peripheral surface of the light-transmitting airtight container to emit light. Halogen bulbs with elevated temperatures up to 3500K have also been used.

Further, small high-pressure metal halide discharge lamps which can be restarted instantly recently have come to be used for headlights for automobiles. This discharge lamp efficiently generates white light with a color temperature of about 5000K and emphasized bluish color, so that it has good visibility and has a small light-emitting portion and is close to a point light source, so light distribution control is easy. In addition, there are advantages such as power saving.

[0006]

However, although the color temperature of the halogen bulb coated with the color filter film is slightly higher than that of the high-pressure metal halide discharge lamp, it is still insufficient.

In addition, the color filter film has a low transmittance in a desired transmission wavelength range, and conversely, the transmittance in a desired cutoff wavelength range does not become sufficiently small.

Further, an infrared reflective interference film can be formed under the color filter film. However, since about 5% of light is shielded in a desired transmission wavelength range, the amount of light shielding is increased as a whole. If the input power is increased, the temperature of the halogen bulb increases, causing temperature damage to the lamp. Further, in some cases, the light-transmitting airtight container may swell during operation or may explode in extreme cases.

On the other hand, a high pressure metal halide discharge lamp is
Since the lamp itself is expensive and requires an electronic lighting circuit, not only is it more expensive, but also there is a problem in terms of weight and size of the lighting system in terms of reducing the weight and size of an automobile.

The present invention generates white light having a high color temperature with an enhanced bluish color, and has the same overall color strength as a conventional automotive halogen bulb having a low color temperature despite having a color filter film. It is an object of the present invention to provide a halogen bulb capable of obtaining a luminous flux, a vehicle headlight and a lighting device using the same.

[0011]

According to the first aspect of the present invention, there is provided a halogen light bulb comprising: a light-transmitting airtight container; a filament positioned substantially on a central axis of the light-transmitting airtight container; An infrared reflective interference film having a transmittance of visible light of 550 nm or less and an average of 80% or more and a wavelength of 550 nm or more and an average of 40% or less; and a halogen and non-transparent film sealed in a transparent airtight container. And an active gas.

In the present invention and each of the following inventions, definitions and technical meanings of terms are as follows unless otherwise specified.

<Transparent Airtight Container> The transparent airtight container is made of a transparent and fire-resistant material such as quartz or hard glass.

[0014] Further, in a halogen bulb, the filament is generally formed in a straight line, so that the shape of the translucent airtight container is a portion located around the filament and surrounding the filament. However, it is allowed that the main part has a cylindrical shape around the filament or a spheroid or pseudo spheroid.

Therefore, the main part of the translucent airtight container is
The radiation mainly contributing to illumination among the radiation of the filament is transmitted through that portion. The portions other than the main portion of the translucent airtight container are, for example, an exhaust chip portion which may be provided at the distal end of the main portion, a neck portion and a sealing portion connected to the base end side of the main portion. .

Further, in order to house the filament in the light-transmitting airtight container in an airtight manner, a pinch seal can be adopted when the light-transmitting airtight container is formed of quartz glass or hard glass. Further, in the case of hard glass, a flare seal, a bead seal, or the like can also be employed.

<Regarding Filament> The filament is disposed substantially on the central axis of the translucent airtight container.

[0018] Also, the filament is advantageously of the double coil type.

Further, the filament is generally formed using a tungsten wire. Furthermore, the support of the filament in the translucent airtight container is not limited to a specific configuration, but as is generally performed, by supporting both ends of the filament by the internal introduction line, It can be carried out.

However, if necessary in order to improve the vibration resistance, the filament can be suspended at an intermediate position and / or both ends using an anchor wire.
The anchor wire holds the single coil portion substantially at the center of the double coil filament, and uses a wire made of a refractory metal such as molybdenum or tungsten.

When an anchor wire is used, the base end of the anchor wire can be embedded and fixed in an exhaust tip protruding from the top of the airtight container. Further, the base end of the anchor wire can be fixed to a suitable insulating member such as a glass bead or a pinch seal. In addition, an internal introduction line can be fixed together to the glass beads.

<Regarding the Infrared Reflective Interference Film> The infrared reflective interference film is formed on the surface of the translucent airtight container. The “surface” means one or both of the outer surface and the inner surface of the translucent airtight container.

The infrared reflective interference film may be formed on the surface of the main part of the light-transmitting airtight container, and may be formed or not formed on other parts. Good.

Further, it is important that the infrared reflective interference film has a property of satisfactorily transmitting visible light in a partial wavelength range described below. That is, the visible light transmittance is 80% or more on average at 550 nm or less, and preferably 85% or more on average, whereas the visible light transmittance is 40% or more on average over 550 nm.
Hereinafter, it is necessary that the infrared reflective interference film is preferably controlled to be 30% or less.

The term "visible light" refers to electromagnetic waves in a wavelength range that can be perceived as light by the human eye. The wavelength range varies among individuals, and generally has a lower limit of 360 to 400 nm and an upper limit of 7 nm.
Since it is said that the wavelength is about 60 to 830 nm and is undefined, in the present invention, the wavelength range of 400 to 780 nm is regarded as visible light.

By the way, if visible light is expressed as light of six colors of purple, blue, green, yellow, orange and red, visible light having a wavelength of 550 nm or less is perceived by human eyes as purple, blue and green color light.

Further, visible light having a wavelength of more than 550 is perceived by human eyes as yellow, orange and red color light.

The "average" of the transmittance refers to an average value obtained by integrating the transmittance for each wavelength within a specific wavelength range. However, the transmittance for each wavelength is 20 n for convenience of measurement.
It can be measured every m.

As is apparent from the above description, the infrared reflective interference film of the present invention emphasizes violet, blue and green color light among visible light emitted from the filament,
Suppresses yellow, orange and red light.

In the present invention, "infrared reflectiveness"
The term "having a property of reflecting near-infrared light having a wavelength of more than 780 to 1500 nm at an average of 50% or more, preferably 60% or more" means that the film has a property of reflecting it. This is because halogen lamps mainly emit near-infrared radiation having a wavelength of 1500 nm or less. In the wavelength range of 1200 to 1500 nm, the transmittance is 60% or less on average, preferably 55%.
Hereinafter, since there is almost no absorption in this region, it is convenient that the reflectance is 40% or more on average, and preferably 45% or more on average.

Further, the interference film having the above-mentioned optical performance can be constituted by a known multilayer interference film.
The multilayer interference film is formed by alternately forming a plurality of thin films having a high refractive index and thin films having a low refractive index. As the thin film having a high refractive index, for example, titanium oxide (TiO2), tantalum oxide (Ta2O5), zirconium oxide (ZrO2), zinc sulfide (ZnS), or the like can be used. As the low refractive index thin film, silicon oxide (SiO2), magnesium fluoride (MgF2), or the like can be used.
As a method of forming a film, a dipping method, a vapor deposition method, a chemical film forming method (CVD) and the like can be adopted. Then, the infrared reflective interference film only needs to be formed on at least most of the main part of the airtight container.

<Regarding Halogen> Halogen encapsulates a trace amount of one or more of iodine, bromine, chlorine and fluorine, and the above-described halogen can be encapsulated alone or as a compound.

Further, by enclosing the halogen in the form of a compound with a hydrocarbon, handling during production can be facilitated. Then, the evaporation of tungsten is suppressed by the halogen cycle, and blackening of the airtight container is prevented.

<Regarding Inert Gas> As the inert gas, a rare gas such as xenon or argon, nitrogen, or the like can be filled at an appropriate pressure.

<Other Configurations> A base can be provided as needed. In the case of a halogen lamp for an automobile, a standardized base that is compatible with a headlight is attached to the sealing portion of the light-transmitting airtight container.

If necessary, a baseless structure without a base can be adopted.

<Regarding the operation of the present invention> In a normal halogen bulb, the filament is incandescent by energization, so that the wavelength generally peaks at 800 to 1000 nm, and the short wavelength side continuously decreases to about 300 nm. In addition, radiation having a relative energy distribution that continuously decreases from near infrared rays to far infrared rays on the long wavelength side is generated. The color temperature is about 3250K.

On the other hand, in the present invention, the wavelength 5
Since the transmittance of visible light at 50 nm or less is 80% or more on average, it transmits violet, blue, and green visible light well, and the transmittance of visible light over 550 nm is 40 on average.
% Or less, transmission of yellow, orange and reddish visible light is suppressed, so that white light with a bluish enhancement as a whole is obtained.

Thus, a halogen bulb having a color temperature of about 5000K can be obtained. This value is equivalent to the color temperature of a high-pressure metal halide discharge lamp used for automobile headlights. Therefore, if necessary, even when the high-pressure metal halide discharge lamp and the halogen bulb are used in combination, no uncomfortable feeling is caused.

In the present invention, since the interference film acts as a wavelength-selective filter for visible light, the visible light transmittance in the transmission wavelength range is significantly increased, and at the same time, the visible light transmittance in the cut-off wavelength range is increased. It is extremely low, in other words, the light blocking ratio can be increased. For this reason, while suppressing the transmission of visible light of yellow, orange, and red series with large specific energy radiated by the filament, purple,
Although the specific energies of the blue and green emission are relatively small, a luminous flux equivalent to the total luminous flux of a halogen bulb having a color temperature of 3500 K provided with a color filter using a conventional pigment can be obtained.

Further, in the present invention, since the transmittance of green light having the highest relative luminous efficiency is large, light emission with high visibility can be obtained. In addition, since the total luminous flux is the same even though the color temperature is extremely high, illumination with extremely high visibility can be performed.

Further, in the present invention, since the infrared reflective interference film reflects the infrared radiation radiated from the filament and returns the same to the filament, the filament is heated by the returned infrared radiation and the conventional infrared reflective film is provided. The luminous efficiency is increased as in a halogen bulb. Further, in addition to infrared rays, most of the visible light having a wavelength of more than 550 nm is reflected by the infrared reflective interference film and returns to the inside of the translucent airtight container and returns to the filament, thereby contributing to the heating of the filament. For this reason, the decrease in luminous efficiency is reduced accordingly.

Further, in the present invention, the above-mentioned effects can be obtained only by providing the infrared reflective interference film. Therefore, it is not necessary to use a coloring filter film together. Therefore, there is no increase in the amount of light shielding by the colored filter, and the temperature rise of the halogen bulb can be suppressed accordingly.

As described above, the halogen bulb of the present invention is suitable for use in automobiles, but it is also effective when used for other purposes such as general lighting in stores and the like.

According to a second aspect of the present invention, there is provided a halogen light bulb, a light-transmitting airtight container, a filament positioned substantially on an axis of the light-transmitting airtight container, and transmission of visible light formed on a surface of the light-transmitting airtight container. The average is 85% or more at a wavelength of 540 nm or less,
An infrared reflective interference film controlled to an average of 35 to 80% in a range from more than 0 nm to 560 nm; and a halogen and an inert gas sealed in a light-transmitting airtight container. .

According to the present invention, a further preferable configuration is defined. Note that the wavelength range from a wavelength of more than 540 to 560 nm is a boundary region between the transmission wavelength range and the cutoff wavelength range, and thus the transmittance greatly changes due to a slight shift in each wavelength range.

According to the present invention, white light emission in which the bluish color is emphasized can be obtained.

According to the third aspect of the present invention, there is provided a halogen light bulb, comprising: a light-transmitting airtight container; a filament positioned substantially on a central axis of the light-transmitting airtight container; and visible light formed on the surface of the light-transmitting airtight container. Among them, it is characterized by comprising an infrared reflective interference film that mainly transmits only violet, blue and green color light; and a halogen and an inert gas sealed in a light-transmitting airtight container.

The present invention defines an arrangement having an infrared reflective interference film controlled so as to favorably transmit only light in the short wavelength region of green light or less among the visible light emitted by the filament. .

Although the structure is defined by color light, the operation is the same as that of the first aspect.

According to a fourth aspect of the present invention, there is provided a halogen lamp according to any one of the first to third aspects.
The translucent hermetic container has a cylindrical portion and a spheroidal shape having a cylindrical portion and a hemispherical portion connected to both ends of the cylindrical portion; the filament has a rod-like shape and a center in the longitudinal direction is transparent. It is characterized by being substantially at the center of the cylindrical portion of the light-tight container or at the center of the long axis between the two focal points of the spheroidal shape;

According to the present invention, depending on the shape of the light-transmitting airtight container,
A configuration in which the feedback of infrared rays to the filament is controlled well to improve the temperature distribution of the filament is defined.

If the filament has a rod shape, the temperature distribution in the longitudinal direction of the filament becomes high at the center and low at both ends, which causes a short life due to early breaking of the filament.

Therefore, it is required to flatten the temperature distribution in the longitudinal direction of the filament, and the present invention can meet this requirement by defining the shape of the light-transmitting airtight container as described above.

In order to satisfy the configuration of the present invention, there are both a pseudo spheroid and a spheroid.

The pseudo spheroid includes a cylindrical portion and a pair of hemispherical portions connected to both ends of the cylindrical portion.

The minor axis of the spheroid has the same value as the diameter of the cylindrical portion. The major axis is a value obtained by adding the axial length of the cylindrical portion to the diameter of the cylindrical portion.

The filament has a rod shape and is arranged substantially coincident with the central axis of the cylindrical portion of the pseudo spheroid or the long axis of the spheroid. When the center of the filament in the longitudinal direction is a pseudo-spheroid, the filament substantially faces the center in the central axis direction of the cylindrical portion, and when the filament is a spheroid, it substantially faces the center between two focal points.

Thus, in the present invention, when the light-transmitting hermetic container is a pseudo-spheroid, both ends of the cylindrical portion in the direction of the central axis substantially act like the two focal points of the spheroid. Thus, the spheroid and pseudospheroid are
In both cases, infrared rays radiated from the respective portions of the filament are reflected by the infrared reflective interference film, and are largely returned to the vicinity of the two focal positions. As a result, the uniformity of the temperature distribution in the longitudinal direction of the filament is improved, and local overheating of the filament is eliminated, so that short life due to early disconnection is less likely to occur.

Further, since the light-transmitting airtight container has a shape of a pseudo-spheroid or a spheroid, the light rays incident on the infrared reflective interference film are almost perpendicular. For this reason, there is little light color shift that occurs when light rays enter the interference film at an angle.

According to a fifth aspect of the present invention, there is provided a halogen lamp according to any one of the first to fourth aspects, wherein:
The translucent airtight container has a cylindrical portion having a radius a at the center portion and a length L of the filament having an axial length of L / 6 to L / 2, and a radius continuous with both ends of the cylindrical portion. a) having a spherical portion; and the filament has a rod-like shape, and its longitudinal center is substantially opposed to the center of the cylindrical portion of the translucent airtight container.

The present invention defines an even more preferable configuration as compared with claim 4. That is, the minor axis is a and the major axis b =
It is possible to obtain a pseudo spheroid substantially the same as the spheroid a + (L / 6 to L / 2). Filament length L
Performs an optical action such that the focal point is located at L / 6 to L / 2 on the center side.

Further, the pseudo spheroid has a cylindrical and hemispherical surface despite performing the same optical action as that of the spheroid, so that the manufacture of the mold becomes extremely easy. There is an advantage that the cost can be reduced as compared with the case of the shape.

According to a sixth aspect of the present invention, there is provided an automotive headlight comprising: a four-light type headlight body having a pair of left and right low-beam headlight bodies and a high-beam headlight body; A high-pressure metal halide discharge lamp installed;
The halogen bulb according to any one of claims 1 to 5, which is disposed as a light source on a high beam headlight body;
It is characterized by having.

In a four-light headlight, the high beam headlights are generally arranged from the center, and the low beam headlights are arranged on both sides. In the present invention, their relative positions are determined. That is, the arrangement does not matter.

The "headlight main body" includes all parts of the headlight except for a lamp serving as a light source. Therefore, when a high-pressure metal halide discharge lamp is used, its lighting circuit is also included.

Further, if the reflecting mirror of the headlight body is manufactured by molding a synthetic resin and vapor-depositing a high-reflectance metal such as aluminum on the reflecting surface, the weight can be reduced.
The accuracy of light control is improved. However, if necessary, a sheet metal or metal may be cast and used as a reflecting surface as it is, or a reflecting mirror may be manufactured by depositing a high-reflectance metal on the reflecting surface.

Further, the front light-transmitting plate may be a transparent transparent synthetic resin body or a glass body, or a prism may be formed in whole or in part to provide a light control action.

Further, it is preferable that the high temperature metal halide discharge lamp and the halogen bulb have substantially the same color temperature of light emission.
If the difference of 0K or less is to some extent, it is practically allowable.

Next, the operation of the present invention will be described.

When the high-pressure metal halide discharge lamp is compared with the halogen bulb of the first to fifth aspects, the former requires a lighting circuit device, and the price including this is too expensive to compare with the latter. In addition, a lighting circuit device is indispensable for a lamp, so that the lamp is large and bulky, and the weight is extremely large. However, since the light emitting portion is small and point-shaped, it is easy to control the light and a sharp light distribution is obtained, and a sufficient luminous flux is obtained with a lamp power of 35 W, thereby saving power.

On the other hand, the halogen lamp of the present invention
On the contrary, it is very inexpensive, small and lightweight. However, it has low luminous efficiency and requires about 70 W of electric power to be used for automobile headlights.

However, they are common in that they can emit white light having a color temperature of 5000 K with blue light emphasized.

By the way, in Japan, many automobiles are concentrated in urban areas. Therefore, when turning on the headlights at night, it is much more common to turn on the low beam than to turn on the high beam.

Therefore, in the present invention, the use of the halogen lamps of claims 1 to 5 for the headlights for the high beam makes it possible to reduce the frequency of use and to reduce the total power consumption. Headlight is obtained.

In addition, since the light source colors of both the low beam and the high beam are uniform, no uncomfortable feeling is given, and since the light is white light, a headlight with good visibility can be obtained.

According to a seventh aspect of the present invention, there is provided a lighting device comprising: a lighting device main body; and the halogen bulb according to any one of the first to fifth aspects supported by the lighting device main body. .

The term “illumination device” has a broad concept including all devices that use the light emitted from a halogen bulb for some purpose. Therefore, for example, it includes not only headlights but also lighting equipment for stores, optical fiber light source devices, display devices, and the like.

The “illumination device main body” means the remaining portion of the illumination device excluding the halogen bulb.

Thus, in the present invention, since the halogen bulb emits white light in which the bluish color is emphasized, a lighting device with good visibility can be obtained.

[0081]

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

FIG. 1 is a front view showing a halogen lamp for an automobile as a halogen lamp according to a first embodiment of the present invention.

FIG. 2 is a front view showing a wire valve state.

FIG. 3 is a side view of the same.

FIG. 4 is a conceptual diagram of a principal part for explaining the shape of the light-transmitting airtight container.

In each figure, 1 is a translucent airtight container, 2 is a filament, 3 is a pair of internal introduction lines, 4 is a pair of external introduction lines, 5 is an infrared reflective interference film, and 6 is a base.

<About Translucent Airtight Container 1> The translucent airtight container 1 is made of hard glass and has a main portion 1a, a neck portion 1b, a sealing portion 1c, and an exhaust chip portion 1d.

The main portion 1a has a pseudo spheroidal shape. That is, as shown in FIG.
And a pair of hemispherical portions 1a2, 1a2.

The cylindrical portion 1a1 has a radius a and a length s in the central axis direction.

The radius of the hemispherical portion 1a2 is a.

The main portion 1a has a pseudo-spheroidal shape having the same effect as the spheroidal shape having the minor axis 2a and the major axis 2b = 2a + s.

The neck portion 1b is formed continuously and integrally with the base end of the main portion 1a.

The sealing portion 1c has a pinch seal structure, and is formed at the base end of the neck portion 1b.

Further, the sealing portion 1c is formed integrally with a substantially horizontal rectangular position regulating protrusion 1c1 at the center of the front and rear decentered planes by using a mold at the time of pinch sealing.

The exhaust tip portion 1d is formed so as to project integrally from the top portion of the main portion 1a. An exhaust pipe is welded to the top of the main part 1a in advance during manufacturing, and after the interior of the main part 1a is evacuated, halogen and an inert gas are sealed and then the sealing is cut off.
d is formed.

<Regarding Filament 2> The filament 2 is made of a rod-shaped tungsten double coil filament, has a length L in the axial direction, and is arranged so that the length direction coincides with the central axis of the translucent airtight container 1. ing. The length s of the cylindrical portion 1a1 of the translucent airtight container 1 in the central axis direction is set so as to fall within the range of the following expression.

L / 6 ≦ s ≦ L / 2 The filament 2 is divided into right and left from both ends.
A pair of coil legs 2 extending at right angles to the axial direction
a and 2b.

<Regarding the pair of internal introduction lines 3> The pair of internal introduction lines 3 extend apart from each other in parallel with the central axis of the translucent airtight container 1, and the base end side is embedded in the sealing portion 1c. Have been.

The tip of the internal introduction wire 3 is stepped in height, and the tip of the inner lead 3 is connected to the pair of coil legs 2a of the filament 2 and the tip of the lower end is connected to the other coil leg 2b. Thus, the filament 2 is supported at a predetermined position.

<Regarding the pair of external introducing lines 4> The pair of external introducing lines 4 have their tips buried in the sealing portion 1c.
And it is butt-welded to the base ends of the pair of internal introduction wires 3, and the other portions are exposed to the outside of the translucent airtight container.

<Regarding the Infrared Reflective Interference Film 5> As shown in FIGS. 2 and 3, the infrared reflective interference film 5 includes the main portion 1a of the translucent airtight container 1, that is, the exhaust tip portion 1c and the neck portion 1b. It is formed in the removed part and has the spectral transmission characteristics shown in FIGS. In FIG. 1, the infrared reflective interference film 5 is expressed as if it is formed so as to be raised or thick on the outer surface of the translucent airtight container 1, but this is the configuration. Is emphasized to make it easier to understand, and the actual thickness is about several to 5 μm.

FIG. 5 is a view mainly showing a wavelength 98 of the infrared reflective interference film in the first embodiment of the halogen lamp of the present invention.
5 is a graph showing spectral transmission characteristics in a region of 0 nm or less together with those of a conventional halogen lamp for an automobile.

FIG. 6 is a graph showing the spectral transmission characteristics of the infrared reflective interference film mainly in the region of a wavelength of 980 nm or more together with those of a conventional halogen lamp for automobiles.

In each figure, the horizontal axis represents the wavelength (nm), and the vertical axis represents the transmittance (%). Curve A shows the spectral transmittance characteristics of the embodiment of the present invention, curve B shows the spectral transmittance characteristics of a conventional halogen bulb having a pigment color filter film, and curve C shows the spectral transmittance characteristics of a conventional halogen bulb having an infrared reflective interference film. Show. In addition, in FIG. 5, each of the curves has a wavelength range from 380 nm to 1000 nm of 20 n.
It is obtained by connecting data measured at m intervals by a straight line.

Note that the curve C matches the curve A at a wavelength of 520 nm or less and a wavelength of 940 nm or more.

As is clear from the figures, the spectral transmittance characteristic of the embodiment of the present invention is, as shown by the curve A, the wavelength 55 nm.
The average transmittance of visible light in the range of 0 nm or less is 84.
The visible light transmittance in a range of 4% and a wavelength exceeding 550 nm is 28.8% on average. Further, the transmittance of visible light in the wavelength range of 540 nm or less is 85.3% on average, and the transmittance of visible light in the range of wavelengths exceeding 560 nm is 2 on average.
The transmittance of visible light in the range of 8.8% and a wavelength exceeding 540 to 560 nm was 70.1% on average. The visible light that does not pass through the infrared reflective interference film 5 mainly in the wavelength range of 560 to 780 nm is the wavelength 780 to 150 described later.
The light is reflected together with the infrared light of 0 nm, returns to the filament 2 inside the translucent airtight container 1, and contributes as a heat source for heating the filament 2.

Next, the spectral reflectance of infrared rays is 780
The average is 75% in the range from more than nm to 1000 nm. Further, it was 41% in the wavelength range of more than 1200 to 1500 nm. In addition, the wavelength exceeding 1500 nm to 2
In the range of 500 nm, the reflectance is not high as in the past,
This range is practically not a problem because the radiation from the filament is also small.

On the other hand, the spectral transmittance characteristic of a conventional halogen bulb having a pigment color filter film is represented by a curve B.
As shown in (2), although the transmittance for visible light other than blue light is suppressed, the transmittance in the entire visible light region is 50% or more, and a sufficient bluish enhancement effect cannot be obtained. Further, no infrared reflection effect is observed.

Next, as shown by a curve C, the spectral transmittance characteristic of the conventional halogen lamp provided with the infrared reflective interference film has a good infrared reflectance, while a visible light transmittance is low. The average is 85% or higher over the entire area. For this reason,
There is no function as a color filter. In addition, the wavelength 120
In the range of 0 to 1500 nm, it was 33.5%.

<Regarding the base 6> As shown in FIG. 1, the base 6 includes a base body 6a, a bulb supporting portion 6b, and a lamp mounting portion 6.
c and a socket mounting portion 6d to support the wire bulb of the halogen bulb shown in FIGS. The “wire bulb” refers to a state before the base of the halogen bulb is attached.

The base body 6a is formed by molding a synthetic resin, has a hollow interior and accommodates a not-shown receiver, and has an inverted L-shape as a whole. The receiver receives the external lead-in wire 4 of the halogen bulb to form a connection,
It is connected to a socket mounting section 6d described later.

The bulb supporting portion 6b fixes the wire bulb of the halogen bulb inserted into the base body 6a accurately at a predetermined position, and fixes it so that it does not undesirably fall off.
In order to surely achieve this, the bulb supporting portion 6b is provided with the position regulating protrusion 1 formed on the sealing portion 1c of the translucent airtight container 1.
The sealing portion 1c is sandwiched between a pair of front and back metal plates 6b2 having the fitting portion 6b1 of c1, and both ends are spot-welded to sandwich the sealing portion 1c.

The lamp mounting portion 6c is a portion for inserting a halogen bulb into a headlight main body (not shown) from the back of the reflector and mounting the same, and includes an O-ring 6c1 and a fixing portion 6c2. .

[0114] The O-ring 6c1 is a waterproof means for mounting the halogen bulb in a watertight manner on the reflector of the headlight.

The fixing section 6c2 fixes the base 6 to the reflecting mirror.

Next, the spectral distribution characteristics of the present embodiment and the conventional halogen lamp will be described with reference to FIGS.

FIG. 7 is a graph showing the spectral distribution characteristics of a general halogen lamp for an automobile having no optical filter film.

FIG. 8 is a graph showing the spectral distribution characteristics of the halogen lamp according to the first embodiment of the present invention.

FIG. 9 is a graph showing the spectral distribution characteristics of a conventional halogen lamp for an automobile having a pigment color filter film.

FIG. 10 is a graph showing the spectral distribution characteristics of a conventional halogen lamp for an automobile having an infrared reflective interference film.

In each figure, the horizontal axis indicates wavelength (nm), and the vertical axis indicates relative energy. The scale indicating the relative energy in each drawing indicates the magnitude of the relative value. That is, the same scale in each drawing means the same energy intensity.

A general halogen bulb contains visible light from violet to red as shown in FIG. 7, but has a spectral distribution characteristic in which the spectral energy intensity increases from violet to red light. .

On the other hand, in the present embodiment, as shown in FIG. 8, an infrared reflective interference film having the transmittance characteristics shown in FIGS. Of the visible light, the violet, blue and green light color components pass through without being absorbed, but most of the yellow, orange and red light color components with large radiant energy are absorbed by the infrared reflective interference film. Therefore, the transmission of light in the visible light range is reduced.

Next, as shown in FIG. 9, a conventional halogen bulb provided with a pigment color filter film has a large amount of blue light components, a large amount of red light components, and yellow and orange cannot be ignored. As many. On the other hand, the green light component is small.

For this reason, the color temperature cannot be increased. Further, the visibility is not sufficient.

On the other hand, as shown in FIG. 10, a conventional halogen bulb having an infrared reflective interference film transmits visible light as it is over almost the entire wavelength range and transmits infrared light of about 800 to
Good blocking over 1500 nm.

Table 1 shows the main characteristics of the halogen lamp used for the present embodiment described above and the conventional high beam for an automobile. The road surface illuminance ratio is data at a distance of 50 m. "Conventional 1" is a general halogen lamp for automobiles not having the optical filter film shown in FIG.
"Conventional 2" is a conventional halogen lamp for automobiles provided with the pigment color filter film shown in FIG. "Conventional 3"
Is a conventional halogen lamp for automobiles provided with the infrared reflective interference film shown in FIG.

[0128]

Table 1 Classification Total luminous flux (lm) Road surface illuminance (lx) Illuminance ratio Color temperature (K) Conventional 1 1850 10.3 1.39 3250 Present embodiment 1700 9.7 1.31 5000 Conventional 2 1700 9.7 1 .31 3500 Conventional 3 2350 13.4 1.81 3320 FIG. 11 is a conceptual diagram of a main part for explaining the shape of a translucent airtight container in the second embodiment of the halogen lamp of the present invention.

In the figure, the same parts as those in FIG. 4 are denoted by the same reference numerals, and description thereof will be omitted.

The present embodiment is different in that the main part has a spheroidal shape.

That is, in this embodiment, the light-transmitting airtight container has a minor axis of 2a, a major axis of 2b, and b = a + (L / 6 to
L / 2).

FIG. 12 is a front view showing a third embodiment of the halogen lamp of the present invention.

The same parts as those in FIG. 1 are denoted by the same reference numerals and description thereof will be omitted.

This embodiment is different in that a light-shielding film 7 is provided on the outer surface of the top portion 1a1 of the main portion 1a of the translucent airtight container 1 and the outer surface of the exhaust chip portion 1d.

That is, the region where the infrared reflective interference film 5 is formed is indicated by a dotted line, but the top portion 1a1 of the main portion 1a and the exhaust chip portion 1
At the base of d, an infrared reflective interference film 5 is formed,
Further, a light-shielding film 7 is formed thereon.

The light-shielding film 7 is black or brown, and its outer surface is preferably non-reflective.

Thus, in the present embodiment, the provision of the light-shielding film 7 allows the infrared-reflective interference film 5 formed on the lower surface of the light-shielding film 7 to reflect infrared light to the filament 2. Works effectively.

However, it is more difficult to form the infrared reflective interference film 5 for the top portion 1a1 and the exhaust tip portion 1d to have a uniform film thickness over the whole of the other main portions 1a. If the thickness of the infrared reflective interference film is not uniform, required visible light transmission control is not performed, and there is a possibility that visible light radiated from the portion to the outside may have an undesired light color. Therefore, since the light-shielding film 7 is formed, by blocking visible light from these portions, undesired light-colored light is not emitted.

Further, since the exhaust chip portion 1d has a discontinuous shape as compared with the main portion 1a of the translucent airtight container 1, the visible light transmitted through the exhaust chip portion 1d disturbs the desired light distribution. Cheap. However, since the light shielding film 7 blocks the emission of visible light from the exhaust tip 1d, the light distribution is less likely to be disturbed.

Further, when the reflected light from the reflecting mirror is incident on the top portion of the translucent airtight container 1 and the exhaust chip portion 1d, the light is re-reflected at these portions and the light distribution is disturbed. Since the reflected light is absorbed, disturbance of the light distribution hardly occurs.

FIG. 13 is a perspective view of a main part of an automobile showing an automobile headlight as an embodiment of the lighting device of the present invention.

FIG. 14 is an enlarged perspective view of an essential part of the headlight, similarly showing the headlight from the back.

FIG. 15 is a front view showing the same high-pressure metal halide discharge lamp.

In each figure, 11 is an automobile, 12 is a headlight, 13 is a high-pressure metal halide discharge lamp, 14
Is a high pressure metal halide discharge lamp lighting device, and 15 is a halogen bulb.

The automobile 11 has a pair of headlights 12 on the left and right of the front part of the body 11a.

The headlight 12 includes a low beam headlight 12a and a high beam headlight 12b.

The low beam headlight 12a is located outside the front surface of the body 11a,
1, a front prism cover 12a2, a high-pressure metal halide discharge lamp 13, and a high-pressure metal halide discharge lamp lighting device 14.

As shown in FIG. 14, the high-pressure metal halide discharge lamp 13 includes an arc tube 13a, an outer tube 13b, an external lead wire 13c, an insulating coating 13d, a base 13e, and the like. Has a color temperature of 500K.

The arc tube 1a is composed of a light-transmitting discharge vessel 1a1 and a pair of electrodes 1a sealed at both ends of the light-transmitting discharge vessel 1a1.
2, 1a2, and an ionizing medium composed of a halide of a luminescent metal, mercury, and a rare gas sealed in the translucent discharge vessel 1a1.

As a rare gas, xenon is sealed at a high pressure, and is configured so that xenon emission first contributes at the time of instantaneous restart.

High pressure metal halide discharge lamp lighting device 1
Reference numeral 4 mainly includes a high-frequency inverter, and turns on the high-pressure metal halide discharge lamp 13 at a high frequency.

The high beam headlight 12b includes a reflecting mirror 12b1, a front prism cover 12a2, and a halogen bulb 12b3.

The halogen bulbs shown in FIGS. 1 to 4 are used.

[0154]

According to the first aspect of the present invention, the filament is positioned substantially on the central axis of the light-transmitting airtight container, and halogen and an inert gas are sealed therein, so that the surface of the light-transmitting airtight container is visible. By forming an infrared reflective interference film whose light transmittance is controlled to 80% or more on average at a wavelength of 550 nm or less, and 40% or less on average at a wavelength of more than 550 nm, violet, blue, and green of visible light are formed. Since it transmits visible light well and suppresses transmission of yellow, orange and red-based visible light, it is possible to obtain white light having a high color temperature with an enhanced bluish color, and infrared light and a wavelength exceeding 550 nm. Since the visible light is reflected and returned to the filament, a halogen bulb having high luminous efficiency can be provided.

According to the second aspect of the present invention, in addition, the infrared reflective interference film is controlled so that the transmittance of the visible light is 85% or more on average at a wavelength of 540 nm or less, and 40 to 80% on the average in a range of a wavelength exceeding 540 to 560 nm. By doing so, it is possible to provide a halogen bulb capable of obtaining white light in which blue is further emphasized.

According to the third aspect of the present invention, the filament is located substantially on the central axis of the translucent airtight container, and halogen and an inert gas are sealed therein. By forming an infrared reflective interference film that transmits only blue and green light, it transmits violet, blue and green visible light well, and yellow, orange and red visible light out of visible light. Since the transmission of light is suppressed, blue light is emphasized, and white light with a high color temperature can be obtained.
Since the infrared rays are reflected and returned to the filament, a halogen bulb having high luminous efficiency can be provided.

According to the fourth aspect of the present invention, the light-transmitting airtight container is a pseudo-spheroid or a spheroid consisting of a pair of hemispheres connected to both ends of the cylindrical portion, and the filament is rod-shaped. Accordingly, it is possible to provide a halogen bulb in which the uniformity of the temperature distribution of the filament is improved and the short life due to the early disconnection of the filament is not easily generated.

According to the fifth aspect of the present invention, in addition, the length of the filament is L, and the transparent airtight container has a radius a and a length L / L.
By comprising a cylindrical portion of 6 to L / 2 and a pair of hemispheres having a radius a, the uniformity of the temperature distribution of the filament, which is good for returning infrared rays, is improved, and the short life due to the breaking of the filament is prevented. It is possible to provide an inexpensive halogen bulb that is easy to manufacture.

According to the sixth aspect of the present invention, a high-pressure metal halide discharge lamp is provided as a light source in the low beam headlight body of a four-light headlight body including a pair of left and right low beam headlight bodies and a high beam headlight body. By installing the halogen bulb according to the first to fifth aspects of the present invention in the high beam headlight main body, it is possible to perform headlight illumination with low power consumption and excellent light distribution control when a normal low beam headlight is used. Infrequently used high-beam lights are inexpensive, small and lightweight light sources, so they are inexpensive, compact and lightweight, and all headlights have high color temperature and excellent visibility, and color temperature It is possible to provide an automobile headlight that has no difference or little discomfort.

According to the seventh aspect of the present invention, it is possible to provide a lighting device having the effects of the first to fifth aspects of the present invention.

[Brief description of the drawings]

FIG. 1 is a front view showing a halogen lamp for an automobile as a first embodiment of a halogen lamp according to the present invention.

FIG. 2 is a front view showing the same wire valve state.

FIG. 3 is a side view of the same.

FIG. 4 is a conceptual diagram of a main part for explaining the shape of the light-transmitting airtight container.

FIG. 5 is a graph showing the spectral transmittance characteristics of the infrared reflective interference film in the first embodiment of the halogen lamp of the present invention together with those of a conventional halogen lamp for an automobile.

FIG. 6 is a view showing a wavelength 98 of the infrared reflective interference film.
Graph showing spectral transmission characteristics in a region of 0 nm or more together with those of a conventional halogen lamp for an automobile.

FIG. 7 is a graph showing a spectral distribution characteristic of a general automotive halogen bulb having no optical filter film.

FIG. 8 is a graph showing the spectral distribution characteristics of the halogen lamp according to the first embodiment of the present invention.

FIG. 9 is a graph showing a spectral distribution characteristic of a conventional automotive halogen bulb having a pigment color filter film.

FIG. 10 is a graph showing a spectral distribution characteristic of a conventional automotive halogen bulb having an infrared reflective interference film.

FIG. 11 is a conceptual diagram of a main part for explaining the shape of a translucent airtight container in a second embodiment of the halogen bulb of the present invention.

FIG. 12 is a front view showing a third embodiment of the halogen lamp of the present invention.

FIG. 13 is a perspective view of a main part of an automobile showing an automobile headlight as an embodiment of the lighting device of the present invention.

FIG. 14 is an enlarged perspective view of an essential part of the headlight, showing the headlight from the back.

FIG. 15 is a front view showing the same high-pressure metal halide discharge lamp.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Translucent airtight container 1a ... Main part 1a1 ... Cylindrical part 1a2 ... Hemispherical part 1b ... Neck part 1c ... Sealing part 1c1 ... Position control protrusion 1d ... Exhaust chip part 2 ... Filament 2a ... Coil leg 2b ... Coil leg 3 ... Internal lead line 4 External lead line 5 Infrared reflective interference film

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // F21W 101: 10 F21Y 101: 00 F21Y 101: 00 F21M 3/02 G

Claims (7)

[Claims] 1. A translucent airtight container; a filament positioned substantially on the central axis of the translucent airtight container; and a visible light formed on the surface of the translucent airtight container having an average transmittance at a wavelength of 550 nm or less. An infrared reflective interference film controlled to be 80% or more and an average of 40% or less at a wavelength exceeding 550 nm; and a halogen and an inert gas sealed in a translucent airtight container. Halogen bulb. 2. A translucent airtight container; a filament positioned substantially on the central axis of the translucent airtight container; and a visible light formed on the surface of the translucent airtight container having an average transmittance at a wavelength of 540 nm or less. 85% or more, more than 540 to 560 nm, and an infrared reflective interference film controlled to an average of 40 to 80% in the range of from 540 to 560 nm; and a halogen and inert gas sealed in a translucent airtight container. A halogen bulb. 3. A light-transmitting airtight container; a filament positioned substantially on a central axis of the light-transmitting airtight container; and a violet, blue, and green type of visible light formed on the surface of the light-transmitting airtight container. An infrared-reflective interference film that transmits only light of the following; a halogen and an inert gas sealed in a light-transmitting airtight container;
A halogen bulb characterized by comprising: 4. The light-transmitting airtight container has a shape having a cylindrical portion and a hemispherical portion continuous with both ends of the cylindrical portion or a spheroidal shape; the filament has a rod-like shape and has a longitudinal shape. 4. The halogen according to claim 1, wherein the center of the direction is substantially at the center of the cylindrical portion of the translucent airtight container or at the center between two spheroidal focal points. light bulb. 5. The light-transmitting airtight container has a central portion having a radius a and an axial length having a length L / 6 of a filament.
円 筒 L / 2 cylindrical portion, radius a continuous at both ends of the cylindrical portion
The filament has a rod-like shape, and the center in the longitudinal direction is substantially opposed to the center of the cylindrical portion of the light-tight airtight container. A halogen bulb according to any one of the above. 6. A four-lamp headlight body including a pair of left and right low-beam headlight bodies and a high-beam headlight body; a high-pressure metal halide discharge lamp disposed as a light source on the low-beam headlight body; A headlight for an automobile, comprising: the halogen bulb according to any one of claims 1 to 5, which is provided as a light source in the headlight body. 7. A lighting device comprising: a lighting device main body; and the halogen bulb according to claim 1 supported by the lighting device main body.