JP2002093365A - High pressure discharge lamp, high pressure discharge lamp device and illumination device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high pressure discharge lamp in which occurrence of crack in the quartz glass discharge container is reduced, and a high pressure discharge lamp device and an illumination device using the same. SOLUTION: A sealing metal foil 3 is airtight embedded in a pair of sealing portions 1b that are integrally installed at the both ends of the surrounding part 1a of the quartz glass discharge container 1. An electrode axis 2a of a diameter of 0.40-0.55 mm and a coil 2b that is wound at the top end of the electrode axis 2a are provided. A pair of electrodes 2 made of pure tungsten of which electrode axis 2a base portions are welded to the sealing metal foil 3 so that the distance between the both electrodes become 2 mm or less are provided. A discharge medium that contains a rare gas and mercury of 0.2 mg/mm3 or more and a halogen of 10×10-3 mol/mm3 more respectively against the inside volume of the surrounding part and that has a mercury vapor pressure of 10 MPa or more at the start of lighting is filled in the surrounding part of the quartz glass discharge container. It is more effective if the holding-in depth at the middle part of the electrode axis of the sealing portion is made 3.5 mm or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-pressure discharge lamp in which the pressure of a discharge medium during lighting is 10 MPa or more, a high-pressure discharge lamp device using the same, and a lighting device.

[0002]

2. Description of the Related Art In recent years, floodlights, image display devices, and the like have become widespread, and high-pressure discharge lamps are often used as light sources. Among them, a short arc type high pressure discharge lamp, which is particularly close to a point light source and easy to control light distribution, such as a xenon lamp and a metal halide lamp, has been widely used as a light source for a liquid crystal projector which has recently become popular.

A liquid crystal projector is a device for projecting an image, and can project not only a still image but also a moving image, and projects various images by inputting a video signal or an image signal of a personal computer. be able to. Therefore, it is used as a tool for presentation, as a simple theater or as a large-screen television monitor, and is used in various fields.

[0004] However, such a liquid crystal projector is
Since it is not so popular that it can be installed in each conference room, it is often carried around, and miniaturization and weight reduction are important issues.

[0005] In order to reduce the size and weight, liquid crystal panels for liquid crystal projectors have been miniaturized year by year, and have reached a size of 1.3 inches. Along with this, the light source has to be efficiently focused on a miniaturized liquid crystal panel.
Miniaturization has been demanded.

To reduce the size of the light source, shortening the arc length is the most optically effective means. However, simply shortening the arc length with the conventional specifications simply reduces the lamp voltage. Resulting in. In order to compensate for this and to supply predetermined lamp power, the lamp current must be increased.

However, an increase in the lamp current leads to an increase in the size of the lighting device, which deviates from the concept of downsizing the liquid crystal projector. Therefore, it is not possible to employ a means for shortening the arc length.

Therefore, in order to shorten the arc length without lowering the lamp voltage, the impedance of the arc is increased, in other words, the pressure of the discharge medium during lighting is increased, for example, in Japanese Patent Laid-Open No. Hei 6-52830. And so on. This type of high-pressure discharge lamp is used in combination with a reflecting mirror to obtain high light-collecting efficiency, and to light the discharge medium at a high pressure of 10 MPa or more in order to improve the color rendering while improving the illuminance maintenance rate. It is a configured mercury lamp. (Prior art 1) The high-pressure discharge lamp of this kind shown in Prior art 1 is optimal for reducing the size and weight because the lighting device can be downsized.

On the other hand, JP-A-11-297269 discloses that, in addition to mercury, a metal halide having an ionization voltage of 0.87 times or less of that of mercury is 2 × 10 ^{−4 to} 7 × 10 ⁻² μm.
mol / mm ^{3 to} the discharge vessel, and using a metal such as Li, Na, Ce, Ba, Ca, etc. as the metal halide, stabilizes the arc satisfactorily and increases the red component to improve the color rendering. A high pressure discharge lamp with excellent light emission is described. (Prior art 2) However, the mercury lamp of prior art 1 still lacks color rendering properties, has a color temperature of 8000K or more, and lacks a red component. Has been requested. For this reason, color rendering properties are improved by using color filters.

However, even if a color filter is used,
Only a certain wavelength component in the light emission distribution is cut to adjust the color balance, which causes a problem that the light emission efficiency is reduced accordingly.

On the other hand, in the prior art 2, although the color rendering property can be improved by adding an alkali metal, the addition of a large amount of the alkali metal easily causes devitrification, and the desired life characteristics cannot be obtained. At the same time, the arc becomes thick and the light collection efficiency may be reduced.

Therefore, the present inventors have completed an invention for improving the above and filed an application as Japanese Patent Application No. 11-370595. The present invention comprises a quartz glass discharge vessel; a pair of electrodes sealed inside the quartz glass discharge vessel; and mercury, a rare gas, a halogen and an alkali metal,
Halogen is 10 ^{− based on} the internal volume of the quartz glass discharge vessel.
³ μmol / mm ³ or more, wherein the alkali metal contains at least Li and the integrated radiation power of the emission spectrum distribution at a wavelength of 402.5 to 407.5 nm is A, and the integrated radiation at a wavelength of 667.5 to 672.5 nm A high-pressure discharge characterized by comprising: an amount of medium satisfying the following expression when the power is B, and a medium sealed in a quartz glass discharge vessel having a pressure at the time of lighting of 10 MPa or more. It is a lamp.

0.15 ≦ B / A ≦ 0.45 According to the above invention, it is possible to improve color characteristics such as color rendering and color temperature without sacrificing light-collecting efficiency, luminous efficiency and life characteristics. it can.

[0014]

However, this type of high-pressure discharge lamp in which the lighting pressure is 10 MPa or more,
As compared with a high-pressure discharge lamp having a relatively low pressure of about 1 to 2 MPa at the time of lighting, there is a problem that cracks are easily generated in the quartz glass discharge vessel during lighting. In addition, "crack" means a crack generated inside a quartz glass discharge vessel, particularly, a sealing portion.

Cracks in the quartz glass discharge vessel that occur during lighting are often caused by the electrodes sealed in the quartz glass discharge vessel. For example, if the diameter of the electrode shaft is too small, the temperature of the electrode will be too high, and the electrode will be consumed by free halogens in the quartz glass discharge vessel. As a result, the consumed tungsten precipitates on the inner surface of the quartz glass discharge vessel, causing blackening of the surrounding portion of the quartz glass discharge vessel. When the blackening progresses, the internal pressure eventually rises due to a rise in the temperature of the surrounding portion, and the surrounding portion expands, and in extreme cases, the quartz glass discharge vessel tends to burst.

If the diameter of the electrode shaft is too large, the consumption of the electrode is reduced, but the difference in thermal expansion between the electrode shaft and the quartz glass increases during the manufacture of the high-pressure discharge lamp. The present invention that causes cracks is a high-pressure discharge lamp in which cracks in a quartz glass discharge vessel are reduced,
An object is to provide a high-pressure discharge lamp device and a lighting device using the same.

More specifically, the present invention provides a high-pressure discharge lamp in which the occurrence of cracks in a quartz glass discharge vessel is reduced by improving the electrodes, and a high-pressure discharge lamp device and a lighting device using the same. Aim.

Further, the present invention provides a high-pressure discharge lamp in which the occurrence of cracks in a quartz glass discharge vessel is reduced by further improving the electrode support structure, and a high-pressure discharge lamp device and a lighting device using the same. With the goal.

[0019]

A high-pressure discharge lamp according to the present invention has a surrounding portion surrounding a discharge space and a pair of sealing portions integrated at both ends of the surrounding portion. A sealing metal foil hermetically embedded in a pair of sealing portions of the quartz glass discharge vessel; and a diameter of 0.40 to 0.55
mm long electrode shaft and coil part wound around the tip of the electrode shaft, the base end is welded to the sealing metal foil, the middle part is held in the quartz glass of the sealing part, and the tip part is surrounded A pair of electrodes made of pure tungsten protruding into the inside of the chamber and having a distance between the electrodes of 2.0 mm or less; a rare gas, 0.2 mg / mm ³ or more of mercury and A discharge medium containing at least a halogen of × 10 ⁻³ μmol / mm ³ or more and enclosed in an enclosure of a quartz glass discharge vessel and having a mercury vapor pressure of 10 MPa or more when turned on. I have.

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

<Regarding the Quartz Glass Discharge Vessel> The quartz glass discharge vessel is a discharge vessel made of quartz glass. If necessary, the inner surface of the translucent quartz glass discharge vessel has halogen-resistant or metal-resistant properties. Forming a transparent coating or modifying the inner surface is acceptable.

In the quartz glass discharge vessel, a surrounding portion is formed at an intermediate portion in the longitudinal direction, and a pair of sealing portions are integrally formed at both ends of the surrounding portion. The surrounding part forms a space surrounding the discharge space inside. The space can be formed in a shape such as a sphere, a spheroid, or a spindle. The pair of sealing portions extend in a rod shape from the surrounding portion, support the electrodes described below inside, seal both ends of the quartz glass discharge vessel, and further supply power to the electrodes via the introducing conductor. It is possible to perform in an airtight manner. In order to achieve this, the electrode and the lead-in conductor are connected with a sealing metal foil in the middle, and the quartz glass of the sealing part is hermetically adhered to the sealing metal foil to seal the quartz glass discharge vessel. Stop. In this case, the pressure resistance can be increased by using a reduced pressure sealing method.

<Regarding Sealing Metal Foil> The sealing metal foil is airtightly embedded in a pair of sealing portions of a quartz glass discharge vessel.
Form an airtight introduction. In general, the sealing metal foil is preferably a molybdenum foil.

<Regarding a Pair of Electrodes> Each of the pair of electrodes is formed of pure tungsten, and has an elongated electrode shaft and a coil portion wound around the tip of the electrode shaft. Note that “pure tungsten” refers to tungsten having a purity of 99.9% or more. The electrode shaft must be set so that its diameter falls within the range of 0.40 to 0.55 mm. If the diameter is less than 0.40 mm, the electrode shaft will be consumed at the time of lighting for about 1000 hours, causing undesirable thinning of the electrode shaft. Further, if the lamp is kept lit as it is, the exhausted tungsten adheres to the inner surface of the surrounding portion of the quartz glass discharge vessel, lowering the screen illuminance or expanding the surrounding portion. If the diameter of the electrode shaft is less than 0.40, inconvenience will occur, which is not possible. On the other hand, if the diameter of the electrode shaft exceeds 0.55 mm, cracks are generated around the contact portion between the electrode shaft and the quartz glass in the sealing portion of the quartz glass discharge vessel, which is not possible. The diameter of the electrode shaft is preferably set to 0.1.
45 to 0.5 mm.

Further, in the present invention, the pair of electrodes are sealed so as to cause a so-called short arc type discharge, as is apparent from the fact that the distance between the electrodes is set to 2.0 mm or less. I have. The short arc type is a so-called electrode stable type in which the arc discharge is stabilized by the electrodes by reducing the distance between the electrodes formed in the translucent discharge vessel. For this reason, the light emission of the high-pressure discharge lamp can be made as close as possible to the point light source, so that the light can be efficiently condensed by an optical system such as a reflector or a lens. The distance between the electrodes is preferably 1.5 mm or less.

Further, the electrode is supported at a predetermined position by holding the intermediate portion of the electrode shaft in the quartz glass of the sealing portion. However, when the intermediate portion of the electrode shaft is welded to the quartz glass, cracks tend to occur in the quartz glass due to the difference in the thermal expansion coefficient between the two. Particularly, since the electrode shaft is made of pure tungsten, the heat between the electrode and the quartz glass is increased. Cracks occur due to differences in expansion coefficients. In order to prevent this, it is possible to wind a fine tungsten wire finely around the electrode shaft at a relatively large appropriate pitch so that the quartz glass comes in loose contact with the thin wire.

<Discharge Medium> In the present invention, the discharge medium enclosed in the surrounding portion of the quartz glass discharge vessel contains at least a rare gas, mercury and halogen. Further, a light-emitting metal can be included as desired.

As the rare gas, argon, krypton, xenon, or the like can be used.

Mercury is added to the inner volume of the quartz glass discharge vessel in an amount of 0.2 mg / mer to obtain a desired lamp voltage.
Enclose mm ³ or more.

Halogen is any of I, Br and Cl
Or one or more kinds, preferably made of Br,
10 × 10^-3μmol /
mm ³The above amount is enclosed. The amount of halogen enclosed is above
If it is less than the lower limit, the arc tends to be unstable. What
In the present invention, the upper limit of the amount of enclosed halogen is specified.
However, inconveniences such as corrosion of the electrode occur as much as possible.
A sensible value is wise, in this case 10
^-2μmol / mm³The degree can be used as a guide.

When a luminescent metal is included as desired, an alkali metal is preferred as the luminescent metal. Among them, when the red light component is increased and the illuminance maintenance ratio is improved, Li may be contained. Further, it is permissible to include a metal such as Na in addition to Li. Note that L
Since the filling amount of i is relatively small, it can be specified by the emission spectrum of the high-pressure discharge lamp rather than directly specifying the filling amount. For example, it is defined by the ratio of the radiation power of Li to the radiation power of mercury in the spectrum, and the wavelength of the emission spectrum distribution is 40
Wavelength 667.5 to 672.5 n for integrated radiation power A with a wavelength width of 5 nm between 2.5 and 407.5 nm
The ratio B / A of the integrated radiation power B having a wavelength width of 5 nm between m and m is defined to be in the range of 0.15 to 0.45. Here, the wavelength 667 m. The integrated radiation power B of 5 to 672.5 nm includes the resonance spectrum of Li. Further, the integrated radiation power A at a wavelength of 402.5 to 407.5 nm includes the resonance spectrum of mercury. By the way, Li
Is less than 0.15, the red component in the emission spectrum is insufficient, and the desired effect cannot be obtained. On the other hand, when the amount of Li exceeds 0.45, the illuminance maintenance ratio decreases.

Further, since the amount of Li to be encapsulated is very small, it can be encapsulated in the form of a mercury halide containing Li at a predetermined ratio without being encapsulated alone.

<Operation of the Present Invention> In the present invention, the diameter of the electrode shaft made of pure tungsten is 0.40 to 0.40.
When the thickness is 0.55 mm, the temperature of the electrode is maintained at an appropriate value, so that consumption of the electrode due to free halogen is reduced. For this reason, it is possible to suppress the thinning of the electrode after lighting for 1000 hours to about 20% or less. Thereby, the blackening of the quartz glass discharge vessel is suppressed, so that the screen illuminance is reduced and the surrounding portion of the quartz glass discharge vessel is less likely to expand. Further, cracks due to contact between the electrode shaft and the quartz glass during the manufacture of the high-pressure discharge lamp are significantly reduced.

Further, since the electrode is made of pure tungsten, the familiarity between the electrode and the quartz glass is improved, which is effective in reducing the occurrence of cracks.

Further, the mercury vapor pressure at the time of lighting is 10 MPa.
With the above, the arc shrinks, so that a high light-collecting efficiency can be obtained.

According to a second aspect of the present invention, in the high-pressure discharge lamp according to the first aspect, the electrode is a pure tungsten thin wire wound around an intermediate portion of an electrode shaft held in quartz glass. Characterized by having a holding coil made of

The present invention defines a configuration in which a nip coil is wound around a portion of the intermediate portion of the electrode shaft which is held by the quartz glass to prevent welding of the quartz glass to the electrode shaft.

That is, the holding coil wound around the intermediate portion of the electrode shaft is made of a fine wire made of pure tungsten, preferably having a diameter of 0.05 to 0.1 mm, similarly to the electrode shaft.
Preferably, the pitch is 100 to 200%.

Then, a winding coil made of a fine tungsten wire is wound around a portion held by the quartz glass at an intermediate portion of the electrode shaft, so that the welding coil is fused with the quartz glass and the electrode shaft. In addition, since the holding coil itself is also made of pure tungsten, welding of quartz glass to the holding coil is effectively prevented. As a result, it is possible to further reduce the occurrence of cracks due to the difference in the coefficient of thermal expansion at the holding portion of the electrode shaft made of quartz glass.

According to a third aspect of the present invention, there is provided the high-pressure discharge lamp according to the first or second aspect, wherein the sealing portion has an indentation depth of 3 mm in which an intermediate portion of the electrode shaft is inflated with quartz glass. 0.5 mm or more.

According to the present invention, the occurrence of cracks in the quartz glass discharge vessel in the holding portion is reduced by defining the holding depth of the electrode axis by the quartz glass in the sealing portion as described above.

That is, the withstand pressure of the quartz glass discharge vessel increases as the gripping depth of the sealing portion with the silica glass in the middle of the electrode shaft increases, but the gripping depth is 3.5 mm. It was found that when the above was reached, the crack generation rate sharply decreased. Conversely, if the gripping depth is less than 3.5 mm, a sufficiently low crack generation rate cannot be obtained. Although the reason for the above is not necessarily clear, since the rupture occurs from the welded portion between the sealing metal foil and the electrode shaft, the larger the grip length is related to the lower the temperature of the welded portion. It is estimated that it is not.

The shape of the end of the holding portion of the quartz glass on the side of the discharge space has a small conical shape extending toward the discharge space from a portion where the quartz glass appears to be in visual contact with the electrode axis. May be formed so as to form a space which is not perpendicular to the electrode axis, or quartz glass may form a surface perpendicular to the electrode axis. The former shape is formed when the sealing portion is sealed by a reduced pressure sealing method centering on the sealing metal foil. Even if the end shape of the holding portion of the quartz glass is any of the above, the holding depth by the quartz glass of the electrode shaft is a portion where the quartz glass appears to be in visual contact with the electrode shaft, It is the distance between the edge of the sealing metal foil.

Further, a gripping coil may or may not be wound around an intermediate portion of the electrode shaft facing the gripping portion of the sealing portion.

Thus, in the present invention, the provision of the above-described structure improves the pressure resistance of the quartz glass discharge vessel and significantly reduces the burst rate.

The high-pressure discharge lamp device according to claim 4 is
A high-pressure discharge lamp according to any one of claims 1 to 3, further comprising: a concave reflector fixed integrally with the high-pressure discharge lamp and surrounding at least a light emitting portion of the high-pressure discharge lamp.

In the present invention, it is appropriate that the high-pressure discharge lamp and the concave reflector are fixed in a predetermined positional relationship by a fixing means such as an inorganic adhesive such as a die cement. However, if necessary, both can be integrally fixed in a detachable form.

In order to fix the high-pressure discharge lamp to the concave reflecting mirror, a base fixed to the sealing portion of the translucent discharge vessel can be used.

Further, the high-pressure discharge lamp does not have to be entirely surrounded by a concave reflecting mirror, and for example, a sealing portion of one electrode may protrude from the concave reflecting mirror to the outside.

Further, as the concave reflecting mirror, one having glass or metal as a base can be used. In any configuration, for example, by employing a dichroic mirror having visible light reflection / heat ray transmission performance on the reflection surface, it is possible to reduce the projection of heat rays on the illuminated surface.

Further, a translucent front cover can be provided in the front opening of the concave reflecting mirror. In this case, the space between the concave reflecting mirror and the translucent front cover can be made airtight. However, it does not have to be airtight. Then, in order to fix the translucent front cover to the concave reflecting mirror, the translucent front cover may be adhered with a silicone adhesive or low-melting glass, or may be mechanically fixed with a metal frame.

Further, by forming a visible light transmitting / heat ray reflecting film on the inner surface or the outer surface of the light-transmitting front cover, the heat rays projected on the illuminated surface can be more effectively blocked.

Further, if necessary, the transparent front cover may be provided with a function of a color filter that transmits light in a specific wavelength range favorably with respect to visible light. However, the inclusion of a small amount of Li makes it necessary to include a red light component. Therefore, it is not necessary to compensate for the shortage of the red light component by cutting the green light component using a color filter.

Thus, the high-pressure discharge lamp device of the present invention is suitable as a light source for a projection device such as a liquid crystal projector. However, it can also be adapted as a light source for lighting equipment such as automobile headlights, spotlights and downlights, and fiber optic lighting devices.

Further, in the present invention, by closing the opening surface of the concave reflecting mirror with the light-transmitting front cover, even if the high-pressure discharge lamp ruptures, the light-transmitting front cover causes the fragments to be surrounded by the light-transmitting front cover. Spattering can be prevented.

According to a fifth aspect of the present invention, there is provided a lighting device, comprising: a lighting device main body; and a high-pressure discharge lamp device according to the fourth aspect, which is disposed in the lighting device main body.

In the present invention, the illuminating device is a broad concept including any device utilizing the light emission of a high-pressure discharge lamp. Therefore, a light projecting device such as a liquid crystal projector and an overhead projector, a vehicle headlight, a lighting fixture, and a display device And an optical fiber lighting device. Of course, the lighting equipment may be either indoor or outdoor.

Thus, according to the present invention, it is possible to obtain a lighting device having improved color characteristics, that is, color rendering and color temperature, without lowering the light-collecting efficiency and the light-emitting efficiency.

[0059]

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

FIG. 1 is a front view showing a first embodiment of the high-pressure discharge lamp of the present invention.

FIG. 2 is an enlarged front view of the same electrode.

In each figure, 1 is a quartz glass discharge vessel,
2, 2 are a pair of electrodes, 3 is a sealing metal foil, 4 is a lead conductor,
5 is a base and 6 is a connection conductor.

The quartz glass discharge vessel 1 is made of quartz glass, and has a central surrounding portion 1a and a pair of sealing portions 1 at both ends.
b, 1b. The surrounding portion 1a has a spheroidal shape with a maximum diameter of 9 mm and an outer diameter substantially close to a sphere, but has an inner surface in a spheroidal shape elongated in the axial direction. The pair of sealing portions 1b, 1b have a length of about 20 mm,
A is integrated with the surrounding portion 1a at both ends by a seal tube connection structure.

The electrode 2 has an electrode shaft 2a, a coil portion 2b, and a holding coil 2c. The electrode shaft 2a is
It is a 0.45 mm pure tungsten rod. Coil section 2b
In this example, a pure tungsten wire of 0.15 mm is double-wound around the tip of the electrode shaft 2a by close winding. The holding coil 2c is formed by winding a pure tungsten fine wire of 0.075 mm at a 150% pitch at least in the middle portion of the electrode shaft at a position facing the holding portion 1b1 made of quartz glass in at least the sealing portion 1b. The distance between the electrodes is 1.4 mm.

The sealing metal foil 3 is made of molybdenum and has a thickness of 20 μm, a width of 1.5 mm and a length of 17 mm. The sealing metal foil 3 is welded to the electrode shaft 2a at one end and the lead conductor 5 to the other end, and is integrated with both ends of the translucent quartz glass discharge vessel 1. Are hermetically buried inside the sealing portions 1b, 1b. Also,
The hermetic sealing between the sealing portion 1b and the sealing metal foil 3 is obtained by a reduced pressure sealing method.

On the other hand, between the sealing portion 1b and the electrode shaft 2a of the electrode 2, the electrode 2 is supported by being loosely contacted without the quartz glass welded by the interposition of the holding coil 2c.

The sealing medium is an alkali metal containing mercury, argon, halogen and at least Li. Mercury is contained in a predetermined amount such that the lamp voltage becomes 80 V or more, and as halogen, Br is 10 × 1 per unit volume of the enclosure 1a.
0 ^{-3 μmol} / mm ³ or more, wherein each and alkali metal contains trace amounts of several tens of ppm of Li Hg
It is sealed as a Br2-Li pellet in the surrounding portion 1a of the quartz glass discharge vessel 1. The noble gas is argon.

The introduction conductor 4 is made of a molybdenum wire, the tip is welded to the sealing metal foil 3, and the base is exposed to the outside from the sealing portion 1b. Although the introduction conductor 4 has a symmetrical structure in the figure, the introduction conductor on the left side is not visible from the outside because it is located in a base 5 described later.

The base 5 has a cylindrical body 5a and a screw terminal 5b. The tubular body 5a is made of a metal such as brass, and one end of the tubular body 5a is fixed to an end of one of the sealing portions 1b by a die cement. The screw terminal 5b has a thread groove formed around it, a base end thereof is fixed to the cylindrical body 5a and protrudes from the cylindrical body 5a to the outside, and is connected to the corresponding introduction conductor 4 inside the screw terminal 5b.

The connecting conductor 6 is made of a nickel wire, and the tip is welded to the introducing conductor 4 projecting outward from the other sealing portion 1b.

Thus, the high-pressure discharge lamp of the present embodiment is lit at a lamp power of 100 to 150 W. Then, a luminous efficiency such that the mercury vapor pressure during lighting exceeds 15 MPa and the amount of light reaching the screen exceeds 10 lm / W is obtained.

FIG. 3 is a graph showing the relationship between the outer diameter of the electrode shaft and the reduction ratio of the electrode shaft in relation to the first embodiment of the high-pressure discharge lamp of the present invention. In the figure, the horizontal axis represents the outer diameter of the electrode axis (mm), and the vertical axis represents the electrode thinning rate (%).

FIG. 4 is a graph showing the relationship between the outer diameter of the electrode shaft and the crack occurrence rate in relation to the first embodiment of the high-pressure discharge lamp of the present invention. In the figure, the horizontal axis indicates the outer diameter of the electrode axis (mm), and the vertical axis indicates the crack occurrence rate (%).

As can be understood from both figures, when the outer diameter of the electrode shaft is in the range of 0.40 to 0.55 mm, the electrode thinning rate becomes about 20% or less and the crack occurrence rate becomes about 1% or less.

FIG. 5 is an enlarged front view of a main part of a high-pressure discharge lamp according to a second embodiment of the present invention. In the figure, the same parts as those in FIG.

The present embodiment is different in that the gripping depth 1 of the gripping portion 1b1 of the sealing portion 1b is regulated to 3.5 mm or more, for example, 5 mm.

The grip depth is in the range indicated by l in the figure. That is, in the present embodiment, since the sealing portion 1b is sealed by the reduced pressure sealing method, the shape of the end of the holding portion 1b1 on the discharge space side is such that quartz glass is visually formed on the electrode shaft portion 2a. Is formed so as to form a small conical space cs extending toward the discharge space from a portion that appears to be in contact with the surface of the quartz glass. It refers to the distance between the part that appears to be in contact and the end of the sealing metal foil 3.

FIG. 6 is a graph showing the relationship between the gripping depth and the withstand pressure of the quartz glass discharge vessel relating to the second embodiment of the high-pressure discharge lamp of the present invention. In the figure, the horizontal axis represents the gripping depth l (mm), and the vertical axis represents the hydrostatic pressure resistance (M
Pa) are shown.

As can be understood from the figure, the hydrostatic pressure resistance increases as the holding depth l increases.
Saturation will eventually occur, but if the holding depth l is 3.5 mm or more, a required hydrostatic pressure of 20 MPa or more can be obtained.

FIG. 7 is a graph showing the relationship between the gripping depth and the frequency of occurrence of lamp rupture relating to the second embodiment of the high-pressure discharge lamp of the present invention. In the figure, the horizontal axis represents the gripping depth l (mm), and the vertical axis represents the lamp burst occurrence frequency (%).

As can be understood from the drawing, if the gripping depth l is 3.5 mm or more, the frequency of occurrence of lamp rupture becomes
0%.

FIG. 8 is an enlarged front view of a main part of a high-pressure discharge lamp according to a third embodiment of the present invention. In the figure, the same parts as those in FIG.

This embodiment is different from the first embodiment in that the shape of the end of the holding portion 1b1 of the sealing portion 1b on the discharge space side is such that quartz glass forms a surface perpendicular to the electrode axis.

FIG. 9 is a partial front sectional view showing an embodiment of the high-pressure discharge lamp device of the present invention.

In the figure, the same parts as those in FIG. 1 are denoted by the same reference numerals, and the description is omitted. 11 is a high-pressure discharge lamp, 12 is a concave reflecting mirror, 13 is an inorganic adhesive, 14 is a relay terminal, 15 is a wire harness, and 16 is a front cover.

The high-pressure discharge lamp 11 has the same structure as that shown in FIG.

The concave reflecting mirror 12 comprises a glass substrate 12a having a concave inner surface, a visible light reflecting / heat ray transmitting film 12b, and a cylindrical portion 12c. The glass substrate 12a has a concave portion on the inner surface formed into a curved surface based on a paraboloid of revolution, and a cylindrical portion 12c integrally formed outside the top portion. The visible light reflection / heat ray transmission film 12b is formed of a dichroic reflection film.

To attach the high-pressure discharge lamp 11 to the concave reflecting mirror 12, the base 5 is inserted into the cylindrical portion 12c, and the light emission center of the high-pressure discharge lamp 11 is matched with the focal point of the concave reflecting mirror 12 so that the base 5 Adhesive 13 between the cylindrical part 12c
To fix both.

The connection conductor 6 is welded to the introduction conductor 5 on one electrode 2 side of the high-pressure discharge lamp 11 and led out to the rear side of the concave reflecting mirror 12. That is, the connection conductor 6 is led out to the back side of the concave reflecting mirror 12 through a through hole 12d formed in a part of the mirror surface.

The relay terminal 14 is fixed near the through hole 12d on the outer surface of the concave reflecting mirror 13. The connection between the connection conductor 6 connected to the high-pressure discharge lamp 11 and the wire harness 15 is relayed.

The wire harness 15 includes a connector 15a and a pair of insulated conductors 15b and 15c. The connector 15 is detachably connected to and connected to a connector at an output end of a lighting device (not shown), and is also connected to one end of the insulated conductors 15b and 15c. The other end of the insulated conductor 15 b is connected to the relay terminal 14. The other end of the insulated conductor 15c is connected to the screw terminal 5b of the base 5 by being tightened with a knurled nut 5c.

The front cover 16 is made of a transparent glass plate, and is adhered to the front opening end of the concave reflecting mirror 12.

When the connector 15a of the wire harness 15 is connected to the lighting device and the high-pressure discharge lamp 11 is turned on, the light rays generated from the high-pressure discharge lamp 11 The light enters the reflective film 12b, and the visible light is reflected and emitted in parallel with the optical axis, passes through the front cover 16, and is used for illumination. On the other hand, heat rays are transmitted through the visible light reflection / heat ray transmitting film 12b, further transmitted through the glass substrate 12a, and radiated to the back side of the concave reflecting mirror 12, thereby suppressing a rise in temperature of the liquid crystal display and the like. can do.

FIG. 10 is a conceptual sectional view showing a liquid crystal projector as one embodiment of the illumination device of the present invention.

In the figure, 21 is a high-pressure discharge lamp device,
22 is a liquid crystal display means, 23 is an image control means, 24 is an optical system, 25 is a high pressure discharge lamp lighting device, 26 is a main body case, and 27 is a screen.

The high-pressure discharge lamp device 21 is the same as that shown in FIG.

The liquid crystal display means 22 displays an image to be projected by liquid crystal, and is illuminated from the back by a high pressure discharge lamp device 21.

The image control means 23 drives and controls the liquid crystal display means 22, and may have a television receiving function if necessary.

The optical system 24 projects the light passing through the liquid crystal display means 22 onto a screen 27.

The high pressure discharge lamp lighting device 25 turns on the high pressure discharge lamp device 21.

The main body case 26 is provided with each of the above elements 21 to 2
6 is stored.

[0102]

According to the first to third aspects of the present invention, a sealing metal foil is hermetically buried in a pair of sealing portions provided integrally at both ends of a surrounding portion of a quartz glass discharge vessel. 0.4
It is provided with an electrode shaft of 0 to 0.55 mm and a coil wound around the tip of the electrode shaft, and is made of pure tungsten in which the base end of the electrode shaft is welded to a sealing metal foil so that the distance between the electrodes is 2 mm or less. A pair of electrodes, each containing at least 0.2 mg / mm ³ or more of mercury and 10 × 10 ⁻³ μmol / mm ³ or more of halogen with respect to the inner volume of the rare gas and the surrounding portion, and mercury vapor at the time of lighting By enclosing the discharge medium having a pressure of 10 MPa or more in the surrounding portion of the quartz glass discharge vessel, it is possible to provide a high-pressure discharge lamp in which the occurrence of cracks in the quartz glass discharge vessel is reduced.

According to the second aspect of the present invention, in addition to the above, the electrode is provided with a holding coil made of a pure tungsten thin wire wound around an intermediate portion of the electrode shaft held in the quartz glass. Further, it is possible to provide a high-pressure discharge lamp in which cracks in the quartz glass discharge vessel are further reduced.

According to the third aspect of the present invention, in addition to the holding depth of 3.5 mm or more holding the middle portion of the electrode axis of the sealing portion by the quartz glass, the withstand voltage is improved. A high-pressure discharge lamp in which cracks are significantly reduced can be provided.

According to the fourth aspect of the present invention, it is possible to provide a high-pressure discharge lamp device having the concave reflecting mirror fixed integrally with the high-pressure discharge lamp and having the effects of the first to third aspects.

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

[Brief description of the drawings]

FIG. 1 is a front view showing a high-pressure discharge lamp according to a first embodiment of the present invention.

FIG. 2 is an enlarged front view of the same electrode.

FIG. 3 is a graph showing the relationship between the electrode shaft outer diameter and the electrode shaft thinning rate in relation to the first embodiment of the high-pressure discharge lamp of the present invention.

FIG. 4 is a graph showing the relationship between the electrode shaft outer diameter and the crack occurrence rate in relation to the first embodiment of the high-pressure discharge lamp of the present invention.

FIG. 5 is an enlarged front view of a main part showing a second embodiment of the high-pressure discharge lamp of the present invention.

FIG. 6 is a graph showing the relationship between the gripping depth and the pressure resistance of a quartz glass discharge vessel relating to the second embodiment of the high-pressure discharge lamp of the present invention.

FIG. 7 is a graph showing the relationship between the gripping depth and the frequency of occurrence of lamp rupture relating to the second embodiment of the high-pressure discharge lamp of the present invention.

FIG. 8 is an enlarged front view of a main part showing a third embodiment of the high-pressure discharge lamp of the present invention.

FIG. 9 is a partial front sectional view showing one embodiment of the high-pressure discharge lamp device of the present invention.

FIG. 10 is a conceptual cross-sectional view showing a liquid crystal display device as one embodiment of the lighting device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Quartz glass discharge container 1a ... Surrounding part 1a1 ... Holding part 1b ... Sealing part 2 ... Electrode 2a ... Electrode shaft 2b ... Coil part 2c ... Holding part coil 3 ... Sealing metal foil 4 ... Leading conductor 5 ... Base 5a: cylindrical body 5b: screw terminal 6: connecting conductor

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiromichi Kawashima 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Inside Toshiba Litec Corporation (72) Inventor Satoko Ishikawa 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo No. Toshiba Litec Co., Ltd. (72) Inventor Tetsuo Otani 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo (72) Inventor Hisashi Yoshida Hisashi 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo (72) Inventor Mamoru Furuya 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo F-term (reference) 5C015 JJ01 QQ32 QQ54 RR01 RR05 SS04 5C039 HH04 5C043 AA14 CC05 DD11 EA09

Claims (5)

[Claims] 1. A quartz glass discharge vessel comprising: a surrounding portion surrounding a discharge space; and a pair of sealing portions integrated at both ends of the surrounding portion; Embedded metal foil; diameter 0.40 to 0.55
mm long electrode shaft and coil part wound around the tip of the electrode shaft, the base end is welded to the sealing metal foil, the middle part is held in the quartz glass of the sealing part, and the tip part is surrounded A pair of electrodes made of pure tungsten protruding into the inside of the chamber and having a distance between the electrodes of 2.0 mm or less; a rare gas, 0.2 mg / mm ³ or more of mercury and A discharge medium containing at least halogen of × 10 ⁻³ μmol / mm ³ or more and enclosed in the surrounding portion of the quartz glass discharge vessel and having a mercury vapor pressure of 10 MPa or more when turned on. High pressure discharge lamp. 2. The electrode according to claim 1, wherein the electrode is provided with a holding coil made of a pure tungsten thin wire wound around an intermediate portion of the electrode shaft held in the quartz glass. High pressure discharge lamp. 3. The high-pressure discharge lamp according to claim 1, wherein the sealing portion has a gripping depth of 3.5 mm or more in which an intermediate portion of the electrode shaft is gripped by quartz glass. 4. A high pressure discharge lamp according to claim 1, further comprising: a reflector fixed integrally with the high pressure discharge lamp and surrounding at least a light emitting portion of the high pressure discharge lamp. A high-pressure discharge lamp device characterized by the above-mentioned. 5. A lighting device comprising: a lighting device main body; and the high-pressure discharge lamp device according to claim 4 disposed in the lighting device main body.