JP2001143658A - High-pressure discharge lamp, light projecting device and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high-pressure discharge lamp, a light projecting device using the high voltage discharge lamp and a projector which increases a bonding strength of a metal foil and a sealing portion and can control generation of a crack of the sealing portion although a high temperature and a high pressure are generated on lighting. SOLUTION: A ribbon-form metal plate which is sealed gas-tightly in a sealing portion of a light-projecting gas-tight vessel formed from a quartz glass to connect electrically an electrode and an outer lead wire and maintains a gas-tightness of the sealing portion is formed so that a shape of a side connected to the electrode satisfies the following requirement; 0.05<=S/L<=0.6, 0.75<=V/W<=0.98, and 0.80<=t/T<=0.98. (L is an entire length mm of a metal foil, S is a length mm of a narrow portion of a metal foil, W is a width mm of a widest portion of a metal foil, V is a width mm of a narrowest portion of a metal foil, T is a maximum thickness mm of a metal foil, and t is a minimum thickness mm of a metal foil).

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 such as a mercury lamp or a metal halide lamp using quartz glass as a light-transmitting airtight container and having a high internal pressure, and an illumination or optical device equipped with the discharge lamp. The present invention relates to a light emitting device and a projector device for displaying images using the light emitting device.

[0002]

2. Description of the Related Art Recently, high-pressure discharge lamps have been employed as light sources for lighting headlights of stores and vehicles and for displaying images on liquid crystal projectors. Further, even in this high-pressure discharge lamp, a short-arc type high-pressure discharge lamp, which is particularly close to a point light source and light distribution control is easy, such as a short metal halide lamp and a xenon lamp, is a recently remarkable liquid crystal projector device. It is widely used as a backlight for a large-screen TV device or a headlight for an automobile or the like.

[0003] For example, a liquid crystal projector is a device for projecting an image, and can project not only a still image but also a moving image. Also, by inputting a video signal or an image signal of a personal computer, various images can be projected, so that it can be used as a presentation tool, or in various fields such as a simple theater or a large screen TV. It is used.

[0004] However, at present, this liquid crystal projector device is expensive and infrequently used, and is not installed in various places in view of cost effectiveness. In many cases, the projector device is carried and used, and is often stored. In particular, since a smaller space is preferable, there is a demand for a smaller and lighter projector device.

To reduce the size and weight of the liquid crystal panel, the size of the liquid crystal panel is reduced year by year, and the size of the liquid crystal panel is about 1.3 inches. In addition, a light source portion used in the miniaturized liquid crystal panel is required to be miniaturized so as to be able to efficiently condense light corresponding to the light source portion.

The most efficient way to reduce the size of the light source is to shorten the arc length of the discharge lamp. However, if the arc length is shortened as in the prior art, the lamp voltage decreases, and accordingly the lamp voltage decreases. There is a problem that the lamp current increases. The increase in the lamp current cannot be adopted because the lighting device becomes large in size and deviates from the target concept of downsizing.

Therefore, in order to shorten the arc length without lowering the lamp voltage, the impedance at the arc is increased, in other words, the amount of the discharge medium is increased so as to increase the pressure in the vessel during operation. I just need.

A lamp having a high pressure during lighting is described, for example, in Japanese Patent Application Laid-Open No. 6-52830. Such a lamp not only reduces the size of the lighting device but also improves the output characteristics of the lamp, making it an optimal lamp for reducing the size and weight.

[0009] For example, during lighting, the pressure in this container is 15M
The short arc type metal halide lamp L9 having a pressure of Pa or more has a structure as shown in a front view in FIG. In FIG. 9, a translucent airtight container 1 made of quartz glass has a bulging portion 12 forming a discharge space 11 at a central portion, and sealing portions 13 extending to both end portions from the bulging portion 12.

The sealing portion 13 is provided in such a manner that a conductive metal body for supplying power to the electrode 5 is hermetically penetrated and sealed in quartz glass forming the hermetic container 1. Molybdenum Mo having a similar thermal expansion coefficient is often used, but its shape is simply a round bar, which is not easily compatible with glass, and has a thin and thick foil shape that absorbs the difference in expansion and contraction between the two.

The metal foils 2 in the sealing portions 13 and 13 have a ribbon-like rectangular shape having a thickness of about 20 μm and a width of about 2.0 mm, and the cross sections thereof are formed at both ends by electrolytic processing or the like. Is thinner, and the cross-sectional shape is flat and substantially rhomboid.

One end of each of the metal foils 2 and 2 has an electrode shaft 3 made of molybdenum (Mo) or tungsten (W) extending into the discharge space 11, and the other end has molybdenum (Mo) or tungsten (W). The external introduction wires 4 whose leading ends are led out of the sealing portion 13 are connected by welding.

The sealing portions 13 and 13 are not formed by heating the glass tube from the surroundings and pressing and squeezing the softened glass tube from outside using a mold such as a pincher. Is formed by baking and shrinking so that the inside of the glass tube is gathered around the center metal foil 2 with a negative pressure, and the cross section of the sealing portion 13 is substantially circular. I have.

Electrodes 5, 5 formed by winding a metal wire such as molybdenum (Mo) or tungsten (W) for several turns are disposed at the positions of the tips of the electrode shafts 3, 3 in the discharge space 11.
Are disposed facing each other with a predetermined discharge gap.

Further, the discharge space 1 of the translucent airtight container 1
1 includes argon Ar and xenon X as a discharge medium.
e, a predetermined amount of mercury Hg and a halogen compound are sealed together with a starting gas such as krypton Kr to constitute a metal halide lamp L9.

However, the short arc lamp L9 as described above has a high pressure in the container 1 during lighting, and at the start of instantaneous lighting or instantaneous relighting immediately after turning off, the lamp current and 20 kV several times that of the stable state. Since the high and low voltage pulses before and after are applied, the temperature of the electrode 5 increases sharply at the time of lighting, and the temperature of the metal foil 2 increases remarkably due to conduction heat and radiation heat from the electrode 5. Then, due to the stress of thermal expansion due to this heat, thermal strain is generated between the metal foil 2 or the electrode shaft 3 of the sealing portion 13 and the quartz glass which is the translucent container 1, and within a relatively short time, this thermal strain is generated. Sealing part 1 of lamp L9 due to thermal strain
3 may have cracks.

A small gap is formed around the electrode shaft 3 located in the sealing portion 13 due to a difference in coefficient of thermal expansion. When the internal pressure increases due to a rise in temperature when the lamp L9 is turned on, the vicinity of the metal foil 2 passes through this gap. Stress is transmitted to
When distortion occurs due to this temperature rise and stress, or when the sealing between the metal foil 2 and the quartz glass varies during the manufacturing stage and distortion or cracks occur in the quartz glass, immediately after lighting due to these, However, there is a problem that the sealing portion 13 ruptures.

Further, as described above, the short arc discharge lamp has a pressure of 15 M in the translucent airtight container during operation.
Due to the high pressure of Pa or more, the stress caused by the blinking of the lamp and the processing distortion during the formation of the hermetic container increase, causing cracks in the sealing portion of the hermetic container. In some cases, not only the container, but also the reflectors, light control bodies, and the like of the equipment provided with the airtight container may be damaged.

[0019]

DISCLOSURE OF THE INVENTION The present inventors have investigated the cracks generated in the sealing portion of the light-transmitting airtight container, and have found that one of the causes is the metal foil.

That is, as shown in FIG. 9 described above, the electrode shaft 3 and the external introduction line 4 for supplying power to the electrode 5 in the airtight container 1 are provided.
The conductive metal foil 2 for making an electrical connection with the substrate is formed in a ribbon-like shape so as to well absorb these differences in expansion and contraction.

The metal foil 2 has a thickness of about 20 μm, which is almost the same for each type, in consideration of the sealing property with quartz glass, and its width can be changed depending on the current capacity and the dimensions of the electrode 5. However, it is designed to be as small as possible due to sealing problems.

The sealing portion 13 of the lamp L9 having such a configuration is described.
In consideration of the above, the connection between the metal foil 2 and the electrode shaft 3 is the largest in terms of capacity and volume with respect to the glass portion. That is, although this connection portion is a member having a similar thermal expansion coefficient, it can be said that there are many extraneous portions existing in the glass and the portion where the distortion is the largest.

It has been found that the connection part having a large distortion is close to the discharge space 11 and is easily broken from a place where the stress is large such as a high temperature and a high internal pressure during lighting. On the other hand, the connection portion between the metal foil 2 and the external introduction wire 4 can be said to be a portion having a large distortion. However, since it is separated from the discharge space 11, the temperature is low and the atmosphere is at atmospheric pressure.

The ribbon-shaped rectangular metal foil 2 embedded in the glass of the sealing portion 13 has a substantially flat cross section by electrolytic polishing or the like in order to alleviate distortion and maintain airtightness. Although it is finished so as to become thinner toward both ends of the rhombus, there are cracks starting from the vicinity of the corner of the metal foil 2 as a starting point, and the glass near the corner has a distortion. It turned out to be concentrated.

At the tip of the corner, small bubbles may remain when the glass melted during sealing contracts. Then, the remaining air bubbles expand due to a rise in temperature at the time of lighting and give stress to the sealing portion 13, or as described above, the minute gap around the electrode shaft 3 is connected to the air bubbles, and the metal halide compound enters. May occur rarely.

For this reason, Japanese Patent Application Laid-Open No. H10-255720 discloses that a metal foil of a discharge lamp is directed toward an electrode joint portion.
A discharge lamp bulb structure having a narrow width (conventional example 1) is described, and JP-A-11-111226 discloses a short arc in which a light emitting space side end of a metal foil is formed in a curved shape. An ultra-high pressure discharge lamp (conventional example 2) is described.

However, as in the conventional example 1 or the conventional example 2, the metal foil is formed narrower toward the light emitting portion side, and the shape of the end portion on the light emitting portion side is formed in a curved shape. Although it was possible to reduce cracks and the like originating from the corners of the foil, it was found that cracks alone could not be sufficiently reduced by other factors.

[0028] For this reason, the present inventors have further improved the structure of the metal foil embedded in the sealing portion to increase the bonding strength between the metal foil and the sealing portion glass. An object of the present invention is to provide a high-pressure discharge lamp capable of suppressing the occurrence of cracks and the like in a sealing portion, a light projecting device and a projector using the high-pressure discharge lamp.

[0029]

A high-pressure discharge lamp according to a first aspect of the present invention is a quartz glass transparent lamp having a bulging portion forming a discharge space and a sealing portion extending to an end side from the bulging portion. A light-tight hermetic container; a ribbon-shaped metal foil hermetically sealed in the sealing portion, having a bulging portion side narrower than an end portion and having the following requirements: 0.05 ≦ S / L ≦ 0.6 0.75 ≦ V / W ≦ 0.98 (L: full length of metal foil mm, S: length of narrow portion of metal foil mm, W: metal Width m of the widest part of the foil
m, V: width of the minimum narrow portion of the metal foil mm) An electrode shaft connected to one end of the metal foil and provided with an electrode at the tip of the side extending into the bulging portion; the other end of the metal foil And a discharge medium which is enclosed in the translucent airtight container.

When the lamp is turned on, the high temperature and high pressure of the translucent airtight container causes stress to be applied to the sealing portion, but the metal foil in the vicinity of the connection between the electrode shaft and the metal foil in the sealing portion must satisfy the above requirements. Since the capacity (volume) of the connecting portion is reduced by making the metal foil narrower than the other side of the metal foil so as to satisfy the material, the amount of foreign materials with respect to the glass is reduced, and the stress can be reduced. Further, in terms of current, there is a rod-shaped electrode shaft capable of taking a larger amount of current than a metal foil, so that there is no need to worry about a cross-sectional area.

If the value of S / L is smaller than 0.05, there is little area for narrowing the metal foil, so that the end of the metal foil on the arc tube side is apt to crack, and the lamp may be damaged at the early stage of the life. There is a danger that this will occur. On the other hand, if the value of S / L is larger than 0.6, the narrow region of the metal foil becomes too large, so that a region where the current density of the metal foil becomes large occurs. For this reason, the temperature of the metal foil rises, so that the temperature of the side connected to the external lead wire of the metal foil rises, and as a result, the metal foil may be blown.

If the value of V / W is smaller than 0.75, the width of the minimum narrow portion of the metal foil becomes too small, so that the current density in that portion becomes large. For this reason, the temperature of the junction between the metal foil and the electrode rises, and the metal foil in the vicinity thereof may expand thermally, possibly increasing the distortion in the sealing portion, and the lamp may be damaged during its life. When the value of V / W is larger than 0.98, the narrow portion of the metal foil is wide, so that the end of the metal foil on the arc tube side is easily cracked, and the lamp may be damaged at an early stage of the life. Occurs.

The present invention relates to a high-pressure discharge lamp such as a short-arc mercury lamp, a short-arc metal halide lamp, a super-high-pressure mercury lamp, a xenon lamp, a general discharge lamp, or the like, using a translucent airtight container made of quartz glass. Applicable to high pressure discharge lamps.

Further, in the translucent airtight container made of quartz glass of the present invention, even if the central bulging portion and the sealing portion at the end portion are integrally formed, the bulging portion is formed at the rear. The sealing part tube may be joined and integrated.

A high-pressure discharge lamp according to a second aspect of the present invention is the high-pressure discharge lamp according to the first aspect, wherein the metal foil has the following requirements. 0.1 ≦ S / L ≦ 0.6 0.75 ≦ V / W ≦ 0.98 (L: full length of metal foil mm, S: length of narrow portion of metal foil mm, W: width m of the widest part of the metal foil
m, V: width of the minimum narrow part of the metal foil mm)

When the value of S / L is smaller than 0.1, the area for narrowing the metal foil is small, so that the processing of the metal foil becomes difficult. For this reason, if the value of S / L is in the range of 0.1 to 0.6, cracks are less likely to occur at the end on the arc tube side, and a high-pressure discharge lamp capable of reducing damage to the lamp during its life can be manufactured by a simple manufacturing method. Can be provided.

A high pressure discharge lamp according to a third aspect of the present invention is a translucent airtight container made of quartz glass having a bulging portion forming a discharge space and a sealing portion extending to an end side from the bulging portion; A ribbon-shaped metal foil that is hermetically sealed in the sealing portion and has a thinner portion on the bulging portion side than the end portion and has the following requirements: 0.05 ≦ S / L ≦ 0.6 0.80 ≦ t / T ≦ 0.98 (where L: total length of metal foil mm, S: length of thin portion of metal foil mm, T: maximum thickness of metal foil mm) , T ...
An electrode shaft connected to one end of the metal foil and provided with an electrode at the tip of the side extending into the bulging portion; and an electrode shaft connected to the other end of the metal foil and It is characterized by comprising: an external introduction line led out of the sealing portion; and a discharge medium sealed in the translucent airtight container.

The reason for setting the S / L range to 0.05 to 0.6 is to achieve the same effect as described in the first aspect.

If t / T is smaller than 0.8, the cross-sectional area of the minimum width portion of the metal foil becomes too small, so that the current density in that portion becomes large. For this reason, the temperature of the junction between the metal foil and the electrode rises, and the metal foil in the vicinity thereof may be thermally expanded, resulting in an increase in distortion in the sealing portion. Therefore, the lamp may be damaged during its life. When the value of V / W is larger than 0.98, the narrow portion of the metal foil is thick, so that the end of the metal foil on the arc tube side is easily cracked, and the lamp is damaged at an early stage of life. May occur.

At this time, the shape of the thin portion of the metal foil may be formed such that the corners are curved. By forming in this manner, the peripheral edge of the metal foil has a smooth curved shape without protruding corners, so that the peripheral edge at the time of sealing is uniformly familiar with glass and does not locally generate strong distortion. In addition, since there is no corner, no minute air bubbles remain near the tip.

A high pressure discharge lamp according to a fourth aspect of the present invention is a quartz glass translucent hermetic container having a bulging portion forming a discharge space and a sealing portion extending to an end side from the bulging portion; A ribbon-shaped metal foil hermetically sealed in the sealing portion, the width of the bulging portion being smaller than the end portion and having a smaller thickness, and having the following requirements: 0.05 ≦ S /L≦0.6 0.75 ≦ V / W ≦ 0.98 0.80 ≦ t / T ≦ 0.98 (where L: total length of metal foil mm, S: narrow width of metal foil) Length of part, W ... Width m of maximum wide part of metal foil
m, V: width of the minimum narrow portion of the metal foil mm T: maximum thickness of the metal foil mm, t: minimum thickness of the metal foil mm) This was connected to one end of the metal foil and extended into the bulging portion. An electrode shaft provided with an electrode at the end on the side; an external lead-in extending to the other end of the metal foil and led out of the sealing portion; and a discharge medium sealed in the translucent airtight container And;

By forming in this way, claim 1
And a high-pressure discharge lamp having the effects of claim 3 can be provided.

A high-pressure discharge lamp according to a fifth aspect of the present invention is the high-pressure discharge lamp according to any one of the first to fourth aspects, wherein the discharge medium has a pressure at the time of lighting of 0.2 mg / g or more. It is characterized by containing mercury of ³ mm or more.

With such a configuration, miniaturization,
It is possible to provide a safe lamp that can achieve high efficiency and can prevent damage due to cracks or the like generated in a sealing portion.

The light emitting device according to claim 6 of the present invention is
It is characterized by comprising a reflecting mirror and the high-pressure discharge lamp according to any one of claims 1 to 5 arranged facing the reflecting mirror.

In the light projecting device in which the high-pressure discharge lamp having the same effect as described in the first to fifth aspects is incorporated in the reflecting mirror, damage to the sealing portion of the lamp due to cracks or the like can be prevented.

The light projecting device of the present invention can be applied to a spotlight for illumination and the like. In addition, it is possible to emit light in a wide wavelength range from an ultraviolet region to an infrared region as well as a radiated light or a visible light castle. In addition, on the front of the reflector,
A lens, a protective cover, and the like may be provided.

The light projecting device of the present invention can be widely used for general indoor and outdoor lighting, store lighting, backlight of projectors, headlights of automobiles and railway cars, and the like.

According to a seventh aspect of the present invention, a projector device according to the sixth aspect, an optical system lens disposed in front of a reflecting mirror of the light emitting device, and a reflection device of the light emitting device. A display screen is provided between the mirror and the optical lens.

Since the projector device of the present invention includes the light projecting device according to the sixth aspect, the projector device according to the sixth aspect has the following advantages.
Has the same effect as described in (1).

The projector device of the present invention can be applied not only to a liquid crystal display screen but also to light irradiation in many fields such as photochemistry, semiconductor production, and imaging.

[0052]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing a high-pressure discharge lamp according to the present invention, for example, a short arc mercury discharge lamp L1.

In the figure, reference numeral 1 denotes a substantially oval light-transmitting airtight container made of quartz glass, a bulging portion 12 forming a discharge space 11 at a central portion, and a sealing portion 1 extending to both ends from the bulging portion 12.
The sealing portions 13 and 13 have a thickness of 15 to 35 μm whose thermal expansion coefficient is close to that of the quartz glass.
Each of the metal foils 2A made of molybdenum Mo in a ribbon shape is sealed.

The electrode shaft 3 extending from the molybdenum Mo, tungsten W, or the like, having a shaft diameter D of 0.3 to 1.3 mm, extending into the discharge space 11 at one end of the metal foils 2A, 2A, On the other end side, an external introduction wire 4 having a wire diameter of 0.4 to 1.0 mm, whose leading end made of molybdenum Mo, tungsten W, or the like is led out of the sealing portion 13, is connected by welding. . Reference numerals 5 and 5 denote a portion of the tip of the electrode shaft 3 located in the discharge space 11 and a metal foil 2A such as tungsten W having a width corresponding to the width of the side 21 to which the external introduction wire 4 on the outer end side of the sealing portion 13 is connected. In comparison, the connection portion 22 side of the discharge space 11 and the electrode shaft 3 is formed narrower.

Further, the sealing portions 13 and 13 are heated by heating the glass tube from the surroundings, and the softened glass tube is gathered from the outside around the metal foil 2A by shrinking and shrinking.
The sealing section 13 has a substantially circular cross section.

The discharge space 1 of the translucent airtight container 1
In a short arc mercury discharge lamp L, a predetermined amount of a water line Hg and an arcon Ar gas are sealed as discharge media.
1.

As a specific example of the lamp L1, the translucent airtight container 1 made of, for example, quartz glass has a total length of about 8 m.
m, the maximum diameter of the bulging part 12 is about 9 mm, the internal volume of the discharge space 11 is about 50 mm ³ , the length of the sealing part 13 is about 25 mm, and the cross-sectional diameter is about 5.5 mm.

Also, a metal foil 2A made of molybdenum Mo
Has a maximum thickness of about 20 μm and a width of the wide portion 21 of about 2 m
m, the length is approximately 17 mm, and the width of the width sandwiching portion 22 is approximately 1.9.
The electrode shaft 3 made of tungsten W wire, which is 5 mm in length and about 4 to 8 mm in length and welded to the narrow portion 22, has a shaft diameter of about 0.4
mm, the length is about 9 mm, and the external introduction wire 4 has an outer diameter of about 0.4 mm and has a length led out of the sealing portion 13.

Also, about 15 mg of mercury Hg is placed in the depositing discharge space 11 so that the lamp voltage becomes about 80 V or more.
Argon gas of about 33.3 kPa (Pascal) at room temperature is sealed.

The short arc mercury lamp L1 having such a configuration is operated at a lamp power of 100 to 150 W,
As a result of increasing the internal pressure during lighting, when the lamp voltage is stable, the electric characteristics of the lamp voltage are about 80 V and about 55 to 60 lm /
The luminous efficiency of W is obtained.

When the lamp L1 is turned on, the temperature of the sealing portion 13 rises to a high temperature, and the inside of the discharge space 11 also rises to a high-pressure atmosphere exceeding 15 MPa (megapascal). Distortion occurs due to a difference in thermal expansion coefficient between the electrode shaft 3 or the metal foil 2A in the portion 13 and the glass. These stresses are applied at a high temperature and in the vicinity of the connection (welding) portion 22 between the metal shaft 2 and the periphery of the electrode shaft 3 that is not completely sealed with the glass in the sealing portion 13.

However, the lamp L1 shown in this embodiment
Since the width or the thickness of the metal foil 2A near the connection (welding) portion 22 in the sealing portion 13 is formed to be narrower or thinner, the number of dissimilar materials decreases with respect to glass and stress is reduced. Damage due to cracks or the like generated in the sealing portion 13 can be prevented. Such a metal foil can be formed by electropolishing.

The sealing portion 13 of the lamp L1 is burned and shrunk to collect the glass at the center and to form a substantially circular cross section, so that the thermal processing distortion is almost uniform in any part, and the high temperature and high pressure are applied. However, damage such as crack generation in the sealing portion 13 can be prevented.

The inventors of the present invention have made various investigations on metal foils, and have obtained the results shown in the following table. It can be seen that the effect of the metal foil is remarkable when the metal foil is within the numerical range described in the claims. Was.

Table 1 shows that the short arc mercury lamp L1 using the same metal foil 2A as shown in the above embodiment was changed from the sample A to the sample L by changing the treatment of the narrow portion 22 of the metal foil 2A. Prototype metal foil 2A of various shapes and form short arc mercury lamp L1 to break the lamp in the initial stage (initial damage), blow out the metal foil during its lifetime (lifetime foil blowout), and in the flashing test The result of investigating the damage situation (flashing test) of the lamp is shown. The metal foil 2A has a total length L of about 17 m.
m, the width W of the wide portion 21 is about 2 mm, and the maximum thickness is about 20 μm.
m, and the shapes of the narrow portions to be joined to the electrodes by the sample are prototyped as follows. (Sample A: length S of the narrow portion 22 is about 5 mm, width V of the narrow portion 22 is about 1.95 mm, and minimum thickness is about 20 μm), (Sample B: length S of the narrow portion 22) Is about 5 mm, the width V of the narrow portion 22 is about 1.5 mm, and the minimum thickness is about 20 μm.
... the length S of the narrow portion 22 is about 5 mm, and the width V of the narrow portion 22
Is about 1.6 mm and the minimum thickness is about 20 μm), (Sample D ...
The length S of the narrow portion 22 is about 1.2 mm, the width V of the narrow portion 22 is about 1.6 mm, and the minimum thickness is about 20 μm.
... The length S of the narrow portion 22 is about 2.9 mm, the width V of the narrow portion 22 is about 2.0 mm, and the minimum thickness is about 18 μm. About 7 mm, the width V of the narrow part 22 is about 1.95 mm, and the minimum thickness is about 16 μm. (Sample G: the length S of the narrow part 22 is about 5 mm, and the width V of the narrow part 22 is (About 1.4 mm, minimum thickness is about 20 μm), (Sample H
... The length S of the narrow portion 22 is about 14 mm, the width V of the narrow portion 22 is about 1.95 mm, and the minimum thickness is about 16 μm. (Sample I: The length S of the narrow portion 22 is about 5 mm) The width V of the narrow portion 22 is about 1.95 mm and the minimum thickness is about 15 μm. (Sample J: the length S of the narrow portion 22 is about 5 mm, and the width V of the narrow portion 22 is about 1 0.5 mm, minimum thickness is about 13 μm), (Sample K
... the length S of the narrow portion 22 is about 5 mm, and the width V of the narrow portion 22
Is about 1.3 mm, and the minimum thickness is about 16 μm. For comparison, a conventional lamp L9 (sample L... Having the same width as that of the above embodiment except for the metal foil except for the above-described embodiment) (a rectangular (long rectangular) ) Has a total length L of about 17 mm and a width W of about 2
(0 mm, V / W: 1.0) were manufactured under the same sealing conditions, and the occurrence of breakage during initial lighting (lighting for 5 minutes) was examined.

[Table 1]

As is clear from Table 1 above, the occurrence rate of breakage at the time of initial lighting and the occurrence rate of non-conformity in the blinking test are higher in the product of the present invention (samples A to G) than in the conventional product (sample L). This proved to be lower than that, confirming that the reliability could be improved.

Further, as for the length of the narrow portion 22 of the metal foil 2A, if the length S of the narrow portion 22 is long, the volume becomes small and the temperature of the metal foil 2A rises. Then, oxidation occurs at the welded portion of the non-hermetic external introduction wire located at the end side of the metal foil 2A, and if this oxidation proceeds, the metal foil 2A is blown out (samples H and K). As described above, when the value of S / L exceeds 0.6, this phenomenon becomes remarkable. Therefore, according to the results of the trial production by the present inventors, the relationship S / L between the length S of the narrow portion 22 and the total length of the metal foil 2A is determined for the length of the metal foil 2A.
Is less than 0.1, the result is close to the sample C in Table 1, and the damage occurrence rate at the time of initial lighting is high. When the S / L exceeds 0.6, the reliability during the life is increased. Is reduced.

If the width of the minimum narrow portion of the narrow portion 22 is too small, the thermal strain on the surface where the electrode shaft 3 and the metal foil 2A are joined increases during the flashing test. In this case, there is a defect that causes inconvenience (sample B).

If the thickness of the minimum narrow portion of the narrow portion 22 is too small, the joining of the electrode shaft 3 and the metal foil 2A during the blinking test is performed in the same manner as when the width of the minimum narrow portion is too small. Since the thermal strain on the surface being heated is large, there is a problem that the spot becomes unsatisfactory during the blinking test (samples J and K).

Therefore, in consideration of the above, the total length Lmm of the metal foil, the length Smm of the narrow portion of the metal foil, the width Wmm of the maximum wide portion of the metal foil, the width Vmm of the minimum narrow portion of the metal foil, the width Vmm of the metal foil, When the maximum thickness of the foil is Tmm and the minimum thickness of the metal foil is tmm, the relationship between them is preferably in the following numerical range.

0.1 ≦ S / L ≦ 0.6

0.75 ≦ V / W ≦ 0.98

0.80 ≦ t / T ≦ 0.98

FIGS. 2 and 3 are enlarged front views showing another embodiment of the introduction conductor portion used in the high-pressure discharge lamp of the present invention. In FIG. 2 and FIG. The description is omitted here.

In the metal foil 2A shown in the above embodiment, the width of the foil to which the electrode shaft 3 is connected is made smaller stepwise than the other side. The configuration of this narrow 22 portion is, for example, as shown in FIG. As in the metal foil 2 </ b> B shown in FIG. 2), some side surfaces on the side of the end are formed as inclined portions 24, 24 tapering toward the end. At this time, if the requirements for the shape of the metal foil fall within the range defined in claim 1, the high-pressure discharge lamp can be suitably configured. As a comparative example, when the side surfaces of the entire metal foil 2C as shown in FIG. 2 (b) are formed as the inclined portions 24, the problems caused by cracks in the vicinity of the metal foil 2C of the sealing portion 13 which have conventionally occurred have been reduced. However, there is a problem that the metal foil is melted during the life at the joint between the external lead wire 4 and the metal foil 2C.

Since the metal foil 2B has a small metal body near the connection (welding) portion 23 in the sealing portion 13 similarly to the metal foil 2A shown in the above embodiment,
With respect to glass, an extraneous material is reduced, thereby reducing stress and preventing the sealing portion 13 from being damaged by cracks or the like.

In the metal foil 2D shown in FIG. 3A, the corner on the side where the electrode shaft 3 is connected is formed not with the above-mentioned right angle or obtuse angle but with a curvature of a curved shape 25, and the portion is formed stepwise. It is formed so as to be thin, so that the foil width on the end side is necessarily narrower than the other side, and the thickness of the foil on the end side is smaller than the other side. Further, the metal foil 2E shown in FIG.
Are formed with a curve 26 having an arbitrary porosity without protruding corners, and the portion is thinner than other portions, as in 2D. When the thickness of the end of the metal foil at this time is t, and the maximum value of the thickness of the other end is T,
It is desirable that the value of t / T be in the range of 0.8 to 0.98.

The metal foils 2D and 2E shown in FIGS. 3A and 3B have the same functions and effects as those of the metal foils 2A to 2C, and protrude from the periphery of the metal foils 2D and 2E. Since it has a smooth curved shape 25 or 26 with no corners, the periphery is uniformly compatible with glass at the time of sealing and there is no local strong strain, so fine bubbles are generated near the tip. Nothing remains.

Accordingly, there is no local distortion or bubbles remaining on the connection portion side of the sealing portion 13 on the electrode shaft 3 side, so that a high-pressure discharge lamp in which cracking of the sealing portion 13 is prevented is provided. be able to. The ends of the metal foils 2D and 2E on the side connected to the external introduction line 4 may be curved 25 or 26. However, the temperature is lower than that on the electrode shaft 3 connection side, and the atmospheric pressure atmosphere is lower. Therefore, the corner may be the same as the conventional one.

FIGS. 4 to 6 are perspective or front views showing another embodiment of the high-pressure discharge lamp of the present invention.
In the drawings, the same parts as those in FIGS. 1 to 3 are denoted by the same reference numerals, and description thereof will be omitted.

First, a lamp L2 shown in FIG. 4 has a double tube structure for a vehicle headlight, a store lighting, and a short tube metal halide lamp L3 having the same shape as the short arc mercury lamp L1. This is a single-sided high-pressure discharge lamp for a backlight of a liquid crystal projector or the like.

The metal halide lamp L3 forming the arc tube has a maximum output of about 6.5 m at a rated output of 35 W.
m, approximately 30 mm in length at both ends of an airtight container 1 made of quartz glass having a substantially elliptical shape having a maximum internal length of approximately 7.0 mm.
3a are formed, and the thickness shown in FIG. 3A is about 25 μm and the width is about 2.0 m in this sealing part.
m, a metal foil 2D made of molybdenum Mo having a length of 15 mm is sealed.

Further, one end of the metal foil 2D has a tip facing the discharge space 11 and has a shaft diameter of about 0.4 mm and a length of about 6 mm.
Electrode shaft 3 made of tungsten W containing thorium Th
However, the other end has a wire diameter of about 0.5 mm and a length of about 3
An external lead wire 4 made of 0 mm molybdenum Mo is connected by spot welding.

In this airtight container 1, about 1.4 mg of Scl-Nal having a mixing ratio of 1: 7 was used as a discharge medium.
About 0.6 mg of a halogen compound and starting gas are used as a starting gas for xenon xe, which is about 5 mg at the time of lighting.
It is sealed at 0 Torr. The lamp power during stable lamp operation is 35 to 45 W, the lamp voltage is 1 to 2 A, and the tube wall load is set to 65 W / cm 2 or more.

The sealing portions 13, 13 of the lamp L3
Is formed by heating the glass tube from the surroundings and forcibly pressing and crushing the softened glass tube from the outside with a mold such as a pincher, and its cross section is almost flat, and the sealing section is The cross section has a substantially rectangular shape of 2 mm × 4 mm.

The metal halide lamp L3 is
It is accommodated in an outer container 10 made of quartz glass having an inner diameter of about 8.5 mm and an inner length of about 45 mm. Both ends 15 of the outer container 10 are reduced in diameter to seal the inner lamp L3. It has a double pipe structure welded to the stoppers 13, 13. In the figure, reference numeral 6 denotes a stainless steel base having a thickness of about 0.2 mm and a width of about 3 m for holding one end of the surrounding container 10.
m, a stainless steel cylindrical support 61 having a diameter of about 11 mm.

The thickness is about 0.1 mm and the width is about 5 mm
Enclosure 10 in which a buffer 62 made of a material having a lower hardness than the base material such as nickel Ni, tantalum Ta, niobium Nb or aluminum Al is used.
Is sealed to the support 61, and the support 61 is compressed by means such as screwing or caulking so as to be held together, and the external lead-in wires 4 protruding from both ends of the internal metal halide lamp L3. 4 (one not shown) is electrically connected to the terminal portion directly or via a lead wire 41.

Then, in the high-pressure discharge lamp L3, the metal foil 2D in the sealing portion 13 is replaced with the metal foil 2 shown in the above embodiment.
Similarly to A, the connection (welding) portion 23 in the sealing portion 13
Is thinned and the periphery is formed in a curved shape by electropolishing. For this reason, foreign materials are reduced with respect to the glass, so that the stress is reduced and damage due to cracks or the like generated in the sealing portion 13 can be prevented. In addition, since the peripheral edge of the metal foil 2D has a smooth shape with no protruding corners, the peripheral edge is uniformly adapted to glass during sealing, so that strong local distortion does not occur and corners are not generated. Since there is no air bubble, no minute air bubbles remain near the tip.

Accordingly, there is no local distortion or bubbles remaining on the connection portion side of the sealing portion 13 on the electrode shaft 3 side, so that a high-pressure discharge lamp L2 in which cracking or the like of the sealing portion 13 is prevented is provided. can do.

The thickness is about 25 μm and the width is about 2.0
The metal foil connecting portion 23 made of molybdenum Mo having a rectangular shape having a thickness of about 0.5 mm is subjected to electrolytic polishing to have a curvature of about 0.5 mm, about 1 mm, about 3 mm, about 5 mm, and a thickness of the section of 22 μm.
m, each of which is processed to have a length of about 2 mm, and the introduced conductor is roughened using these metal foils 2D, and the short arc metal halide lamp L3 shown in the above-described embodiment is formed.
Were produced in each case.

For each of the five metal halide lamps L3, the lighting power is 70 W, the stable power rating is 35 W,
Lighting 9 minutes 45 seconds under conditions of 20 kW pulse pressure at start-
The lights were turned on and off repeatedly for 15 seconds, and for each of the remaining five lamps, a lighting power of 84 W, a stable power rating of 42 W, and a starting pulse voltage of 2, corresponding to a 20% increase in the above conditions.
Under the condition of 0 kW, blinking for 3 minutes and turning off for 3 minutes were repeated, and a visual inspection was performed for the state of occurrence of hooks in the sealing portion 13.

As a result, in each lamp L3 manufactured using the metal foil 2D of each curvature, the total number was about 7,000 times under the former condition, and the total number was about 2 times under the latter condition.
Even when the lamp was flashed 5000 times, the lamp L3 in which cracks occurred in the sealing portion 13 was not found, and good results were obtained.

In this type of lamp L3, the same results as above were obtained even if the lamps with different ratings, the type and amount of the metal halokene compound, the type of starting gas and the pressure, the structure of the electrodes, etc. were changed. .

The lamp L2 of this embodiment has a buffer 61 made of a material having a lower hardness than the material for forming the base 6, such as nickel Ni, tantalum Ta, niobium Nb, or aluminum AI, in the support 61 of the gold 6. Since the lamp L2 is fixed by interposing it, a temperature change due to the blinking of the lamp L2, a forced test such as applying a vibration and impact to the lamp L2,
No crack was found in the sealing portion 13, or no metal was loosened or dropped from the surrounding container 10.

The high-pressure discharge lamp L4 shown in FIG.
The discharge lamp L1 is of a general type having a double tube structure.
Alternatively, L3 is supported on lead wires 71, 72 of stem 7 via band members 73, 73, and this stem 7 is housed and sealed in an envelope 10 made of hard glass or quartz glass. It is.

The discharge lamp L4 is also sealed in the sealing portion 13.
Since no local distortion or bubbles remain on the connection portion side of the electrode shaft 3, cracks and the like in the sealing portion 13 can be prevented.

Further, a discharge lamp L composed of these double tubes is used.
2 and L4 are heat insulation and lead wires 7 of the internal lamps LI and L3.
In addition to preventing oxidation of the lamps 1 and 72 and blocking ultraviolet rays, they protect the internal lamps L1 and L3 when the airtight container 1 ruptures.

The high-pressure discharge lamps L1 to L4 shown in FIGS. 1 to 5 have sealing portions 1 at both ends of a quartz glass tube.
3 and 13 were formed, but the high-pressure discharge lamp L5 shown in FIG.
The sealing member 13 is formed at one end of the translucent airtight container 1 by a mold such as a pincher.
In F and 2F, an inclined portion 27 is formed on one side surface on the connection portion side with the electrode shaft 3.

[0099] Even in the case of the one-side sealed lamp L5, the same operation and effect as those of the above-described embodiment can be obtained.

FIG. 7 is a partially sectional front view showing an embodiment of a light projecting device 7 of the present invention incorporating the short arc discharge lamp L1 or L3, and FIGS.
The same parts are denoted by the same reference numerals, and description thereof is omitted.

In FIG. 7, reference numeral 6 denotes a lamp L1 or L3.
And a terminal portion 63 attached to one sealing portion 13 of the translucent airtight container 1 and connected to the external introduction line 4, the terminal portion 63 and the other external introduction line 4 are connected to the power supply lines 72 and 73. The power supply 71 is connected to the lighting power supply 71 via the power supply.

Reference numeral 8 denotes a reflecting mirror formed of a material such as glass or metal, and has a light reflecting curved surface 81 which forms a quadratic curved surface such as a paraboloid of revolution or an ellipsoid of revolution. Is the short arc discharge lamp L1 (with gold 6 or L3)
... the same applies hereinafter) to the base cylindrical portion 8 for fixing the 6 portions of the base.
2 protrudes from the body. 6 parts of the gold of the lamp L1 (L3) are inserted into the base cylindrical part 82, and are fixedly joined with a heat resistant adhesive 83 mainly composed of silica and alumina.

Reference numeral 84 denotes a light interference film such as a dichroic film formed on the light reflecting curved surface 81 or a total light reflecting film made of chromium, aluminum, silver or the like.
And a low-refractive-index layer made of silicon oxide Si02.

The light projecting device 7 having such a configuration is supplied with electricity from the lighting power supply device 71 and is supplied with the short arc discharge lamp L1.
When (L3) is turned on, part of the light from the lamp L1 (L3) is direct light and part of the light is incident on the visible light transmitting infrared reflecting film 84, and the visible light becomes reflected light to form the reflecting mirror 8 It is emitted forward of The infrared light incident on the visible light transmitting infrared reflecting film 84 passes through the reflecting film 84 and the reflecting mirror 8 and is emitted to the rear of the reflecting mirror 8, and visible light with less heat rays can be emitted in front of the reflecting mirror 8. . Also, on the front of the reflector,
A lens, a protective cover, and the like may be provided.

The short arc discharge lamp L1 (L3) attached to the reflecting mirror 8 also has the metal foil 2A (2
Since the portion to which the electrode shaft 3 is connected in D) is formed to be narrow, even if the sealing portion 13 becomes hot at the time of lighting or the inside of the discharge space 11 becomes a high-pressure atmosphere, the sealing portion 13 is formed. Glass can be prevented from being damaged such as cracks and leaks. Therefore, the light emitting device 7 having the same operation and effect as described above.
Can be provided.

FIG. 8 is a schematic diagram showing an embodiment of a liquid crystal projector 9 of the present invention using the above-mentioned light projecting device 7. In the figure, the same parts as those in FIG. The description is omitted.

In FIG. 8, reference numeral 91 denotes an optical system lens;
Denotes a projection surface such as a screen, and a liquid crystal screen 93 is provided as a display screen between the light projecting device 7 and the optical system lens 91.

The liquid crystal projector 9 transmits the light radiated from the lamp L 1 (L 3) in the light projecting device 7 to the reflecting mirror 8.
And projects the image on a projection screen 92 via an optical system lens 91. An image displayed on a liquid crystal screen 93 disposed between the light projecting device 7 and the optical system lens 91 is projected onto the projection screen 92. It is designed to be enlarged and projected.

The lamp L1 (L3) in the light projecting device 7 provided in the projector device 9 can also prevent damage such as cracks and leaks in the glass of the sealing portion 13 at the time of lighting, and thus has a short life. There is no danger of becoming Therefore,
Since the light projecting device 7 having the above-described operation and effect is provided, it is possible to provide the liquid crystal projector device 9 which does not require replacing the light projecting device 7 in a short time.

The present invention is not limited to the above embodiment. For example, the high-pressure discharge lamp is not limited to the above-described short arc type discharge lamp, and halogens such as iodine and bromine as halogens, scandium Sc, sodium Na, thallium Tl, indium ln, tin Sn, dysprosium Dy, aluminum Al, Metal halide lamps filled with halides of metals such as zinc Zn, manganese Mn, holmium Ho and thulium Tm, ultra-high pressure mercury lamps and xenon lamps filled with high pressure xenon gas may be used. The lamp is not limited to the circular shape, and may be an elliptical shape, a spherical shape, a straight tube shape, or the like.

The present invention also relates to a high-pressure discharge lamp, such as a general mercury lamp or a metal halide lamp, in which the pressure in the discharge space of the container does not become too high and the sealing is formed into a substantially rectangular cross section using a pincher. Of course, it can be applied.

The electrodes of the high-pressure discharge lamp according to the present invention are not limited to those in which a coil is wound around the electrode shaft, and the tip of the electrode shaft itself may be used as an electrode or an electrode on an individual may be provided. In the lamp to be turned on, the cathode side electrode and the anode side electrode may have different specifications. Further, the welding means for connecting the metal foil and the electrode shaft is not limited to spot welding, but may be applied by other welding means such as resistance welding, arc welding and plasma welding.

Further, the lamp, the light projecting device and the projector device of the present invention are not limited to those described in the embodiments, and can be applied to light irradiation in many fields such as illumination, photochemistry, semiconductor manufacturing, and imaging. is there.

[0114]

According to the first aspect of the present invention, the width of the metal foil portion to which the electrode shaft is connected is reduced, and the shape of the metal foil is defined to reduce the stress of the sealing portion. Thus, it is possible to provide a high-pressure discharge lamp having a long life and improved quality, in which damage due to cracks or the like generated in the sealing portion can be prevented.

According to the second aspect of the invention, in addition to the effect of the first aspect, by using a metal foil which is easy to manufacture, a high-pressure discharge lamp which can be easily manufactured can be provided.

According to the third aspect of the present invention, the thickness of the metal foil portion to which the electrode shaft is connected is reduced, and the shape of the metal foil is defined to reduce the stress of the sealing portion. Thus, the present invention can provide a high-pressure discharge lamp having a long life and improved quality, which can prevent damage due to cracks or the like generated in the sealing portion. Further, it is possible to provide a high-pressure discharge lamp having improved quality with a long life without strong distortion or bubbles remaining locally, and with little risk of cracks, leaks or the like occurring in the sealing portion.

According to the fourth aspect of the present invention, a high-pressure discharge lamp having the effects of the first or third aspect can be provided.

According to the fifth aspect of the present invention, the effect of any one of the first to fourth aspects is obtained, and further, the high-pressure discharge lamp can be reduced in size and increased in efficiency.

According to the sixth aspect of the present invention, in the case where the high-pressure discharge lamp having the effects described in the first to fifth aspects is incorporated in a reflecting mirror, high quality and high reliability without short life is generated. It is possible to provide an improved light emitting device.

According to the seventh aspect of the present invention, there is provided a projector having a high-quality and high-reliability projector which does not have a short life and is provided with a light projecting device having the effects described in the sixth aspect. .

[Brief description of the drawings]

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

FIGS. 2 (a) and 2 (b) are enlarged front views showing another embodiment of the introduction conductor portion used in the high-pressure discharge lamp of the present invention.

FIGS. 3 (a) and 3 (b) are enlarged front views showing another embodiment of the introduction conductor portion used in the high-pressure discharge lamp of the present invention.

FIG. 4 is a perspective view showing another embodiment of the high-pressure discharge lamp of the present invention.

FIG. 5 is a front view showing another embodiment of the high-pressure discharge lamp of the present invention.

FIG. 6 is a front view showing another embodiment of the high-pressure discharge lamp of the present invention.

FIG. 7 is a partial sectional front view showing an embodiment of a light projecting device of the present invention.

FIG. 8 is a schematic explanatory view showing an embodiment of the projector device of the present invention.

FIG. 9 is a front view showing a conventional high-pressure discharge lamp.

[Explanation of symbols]

L1, L3: High pressure discharge lamp arc tube (short arc discharge lamp) L2, L4: High pressure discharge lamp (double tube discharge lamp) L5: High pressure discharge lamp (single-side sealed discharge lamp) 1: Translucent airtight container 11: Discharge space 12: Swelling portion 13: Sealing portion 2A to 2F: Metal foil 22: Narrow portion 24, 27: Inclined portion 25, 26: Curved portion 3: Electrode axis 4: External introduction line 5: Electrode 7 : Light projecting device 8: Reflecting mirror 9: Projector device (liquid crystal projector device) 91: Optical lens 93: Display screen

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuo Otani 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Inside Toshiba Litec Corporation (72) Inventor Hisashi Yoshida 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo (72) Inventor Satoko Ishikawa 4-3-1 Higashi-Shinagawa, Shinagawa-ku, Tokyo In-house Toshiba Litec Corporation (72) Inventor Yasutaka Gogami 3-3-1 Shinmachi, Ome-shi, Tokyo 1 In-house Toshiba Digital Media Engineering Co., Ltd. (72) Inventor Hiroyuki Kato 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Inside (72) Inventor Nansei Murase 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo No. 1 Toshiba Litec Co., Ltd. (72) Inventor Atsushi Saita 4-3-1 Higashi Shinagawa, Shinagawa-ku, Tokyo (72) Inventor Toshihiko Ishigami 4-3-1, Higashishinagawa, Shinagawa-ku, Tokyo Toshiba LITEC Corporation (72) Inventor Mikio Matsuda 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Inside Itec Co., Ltd. (72) Inventor Kozo Uemura Toshiba Litec Co., Ltd. 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo

Claims (7)

[Claims] A translucent airtight container made of quartz glass having a bulging portion forming a discharge space and a sealing portion extending to an end portion thereof, and an end hermetically sealed in the sealing portion. And a ribbon-shaped metal foil formed so that the bulging portion side is narrower than the bulging portion side and has the following requirements: 0.05 ≦ S / L ≦ 0.6 0.75 ≦ V / W ≦ 0. 98 (however, L: total length of metal foil mm, S: length of narrow portion of metal foil mm, W: width m of maximum wide portion of metal foil
m, V: width of the minimum narrow portion of the metal foil mm) An electrode shaft connected to one end of the metal foil and provided with an electrode at the tip of the side extending into the bulging portion; the other end of the metal foil A high-pressure discharge lamp, comprising: an external lead-in connected to the side and led out of the sealing portion; and a discharge medium sealed in the translucent airtight container. 2. The high-pressure discharge lamp according to claim 1, wherein the metal foil has the following requirements. 0.1 ≦ S / L ≦ 0.6 0.75 ≦ V / W ≦ 0.98 (L: full length of metal foil mm, S: length of narrow portion of metal foil mm, W: width m of the widest part of the metal foil
m, V: width of the minimum narrow part of the metal foil mm) 3. A translucent airtight container made of quartz glass having a bulging portion forming a discharge space and a sealing portion extending to an end portion thereof; an end hermetically sealed in the sealing portion. And a ribbon-shaped metal foil formed so that the thickness of the bulging portion side is smaller than that of the bulging portion side and having the following requirements: 0.05 ≦ S / L ≦ 0.6 0.80 ≦ t / T ≦ 0 .98 (however, L: total length of metal foil mm, S: length of thin portion of metal foil mm, T: maximum thickness of metal foil mm, t ...
An electrode shaft connected to one end of the metal foil and provided with an electrode at the tip of the side extending into the bulging portion; connected to the other end of the metal foil and sealed. A high-pressure discharge lamp, comprising: an external introduction line led out of the stop; and a discharge medium sealed in the translucent airtight container. 4. A translucent airtight container made of quartz glass having a bulging portion forming a discharge space and a sealing portion extending to an end thereof, and an end hermetically sealed in the sealing portion. And a ribbon-shaped metal foil which is formed narrower and thinner on the bulging part side than the part side and has the following requirements: 0.05 ≦ S / L ≦ 0.6 0.75 ≦ V / W ≦ 0.98 0.80 ≦ t / T ≦ 0.98 (L: full length of metal foil mm, S: length of narrow portion of metal foil mm, W: maximum of metal foil Wide part width m
m, V: width of the minimum narrow portion of the metal foil mm, T: maximum thickness of the metal foil mm, t: minimum thickness of the metal foil mm) is connected to one end of the metal foil and extends into the bulging portion. An electrode shaft provided with an electrode at the leading end of the projecting side; an external lead-in extending to the other end of the metal foil and led out of the sealing portion; and enclosed in the translucent airtight container. A high-pressure discharge lamp, comprising: a discharge medium. 5. The high-pressure discharge lamp according to claim 1, wherein the discharge medium contains 0.2 mg / mm ³ or more of mercury at a lighting pressure of 20 MPa or more. 6. A light projecting device comprising: a reflecting mirror; and the high-pressure discharge lamp according to claim 1 disposed facing the reflecting mirror. 7. A light projecting device according to claim 6, an optical system lens disposed in front of a reflecting mirror of the light projecting device, and a space between the reflecting mirror and the optical system lens of the light projecting device. And a display screen arranged in the projector.