JPH1173917A - High-presure discharge lamp and illuminating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the sealing work, without having the possibility of off- centering or leakages in confronting electrodes by providing an inner lead bar having an electrode at the top on the side protruded into a swollen part through a separator, provided adjacent to a cylindrical body within a hold tube or the cylindrical body. SOLUTION: In a sealing work, internal and external lead bars 5A, 5b and a separator 6S are sealed in the state, where they are held substratially on the central axis of a sealing tube part 3, and the glasses of the sealing tube part 3 or a hold tube 6H strongly heated near a heat source such as gas burner are fused well, and they are mutually fluidized, fused together and integrated. Since the part closer to the central part of the internal and external lead bars 5A, 5B and the separator 6S held substratially on the central axis are not laid in fused state, and regularly enclosed by the hold tube 6H situated outside, consequently they hardly move and are held substantially on the central axis of the sealing tube part 3, even after sealing.

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 using quartz glass as a light-transmitting container, and more particularly to a structure of an introduction body of a sealing portion having a large current and a light irradiation device using the discharge lamp.

[0002]

2. Description of the Related Art High pressure discharge lamps such as short arc metal halide lamps, ultra-high pressure mercury lamps and xenon lamps using quartz glass in a light-transmitting container have various uses as compact light sources having only an arc tube without an outer tube. Used in

The above-mentioned short arc metal halide lamp is used for light irradiation in many fields such as photochemistry, semiconductor manufacturing, and imaging. For example, in semiconductor manufacturing, exposure of a wafer is performed using ultraviolet rays emitted from the lamp. Is being done. Recently, it has been studied to shorten the exposure time and increase the exposure area by increasing the power, and with the demand for a smaller device with a higher power, a smaller lamp is required. I have.

[0004] In these lamps, which have been reduced in size with the increase in power, a metal foil made of molybdenum foil or the like is used for a sealing portion for maintaining airtightness with quartz glass constituting the translucent container. The introduced body is sealed. Usually, the thickness of this molybdenum foil is 20 to 30 μm. If it is thicker than this, cracks or airtightness cannot be maintained in the quartz glass bulb due to the coefficient of thermal expansion. Not only does foil breakage occur during sealing or lighting, but also current is limited. Therefore,
High power type lamps of 1kW and 2kW with this kind of lamp,
A plurality of the sealing metal foils are used in parallel. For example, an introduction body 4 of a short arc metal halide lamp L using two metal foils is shown in FIGS.
The configuration is as shown in FIG. Molybdenum foils 5M, 5M as metal foils are welded to flat portions 5F, 5F formed by cutting the upper and lower surfaces of both ends of inner lead bar 5A and outer lead bar 5B made of, for example, tungsten or molybdenum holding electrode 7. A separator 6S made of rectangular flat quartz glass is interposed between the molybdenum foils 5M, 5M and between the end faces of the inner lead rod 5A and the outer lead rod 5B. 6T is a cylindrical body made of quartz glass, which penetrates the internal lead rod 5A.

[0005] The introduction body 4 having such a configuration has sealing tube portions 3 and 3 (only one end is shown) extending to both ends from a bulging portion 2 forming a light emitting space of a translucent container 1 made of quartz glass. The cylindrical body 6T and the separator 6S are inserted into the sealing tube 3
It is supported by abutting against the inner wall. (In some cases, only the cylindrical body 6T is in contact.) When the inside of the container 1 is heated from the outside in a vacuum or a low-pressure inert gas atmosphere, the sealing tube 3 1B, the cylindrical body 6T, and the separator 6S are softened and melted, and the diameter of the sealing tube 3 is reduced. This heating melts not only the sealing tube portion 3 but also the surfaces of the inner cylindrical body 6T and the separator 6S,
The glass of the sealing tube 3 is made of a cylindrical body 6T and a separator 6S.
And the molten glass covers the molybdenum foils 5M, 5M and is hermetically sealed.

[0006] However, the above-mentioned introduction body 4 is a sealing tube part 3.
The inside of the sealing pipe 3 is supported by a cylindrical body 6T penetrating the internal lead rod 5A, but has a relatively large diameter because the electrode 7 needs to pass through. If the gap between the outer diameter of 6T and the separator 6S is large, the sealing tube 3
The lead rod 5A may be inclined with respect to the central axis, and the position of the electrode 7 at the tip may be largely eccentric.

Further, the molybdenum foils 5M, 5M extend due to the heating during the sealing and shift the position of the separator 6S. And the molybdenum foil 5M may be cut, resulting in a significant decrease in yield.

[0008]

The problems to be solved are to prevent deformation and eccentricity of the introduced body sealed in the sealing tube at the end of the translucent container, to prevent deformation of the sealing tube and to prevent deformation. It is difficult to perform sealing work.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to improve the matching between a sealing tube at the end of a translucent container and an introduction member inserted into the sealing tube. It is an object of the present invention to provide a high-pressure discharge lamp that does not cause eccentricity or leakage and that can be easily sealed, and a light irradiation device using the lamp.

[0010]

According to a first aspect of the present invention, there is provided a high-pressure discharge lamp made of quartz glass having a bulging portion forming a light emitting space and sealing tube portions extending to both ends thereof. A container, a quartz glass hold tube provided substantially over the entire inner circumference of the sealing tube portion, a quartz glass tubular member provided near a bulge portion in the hold tube, and a cylindrical tube in the hold tube. A flat separator made of quartz glass provided adjacent to the body, a pair of metal foils provided almost in parallel along the upper and lower flat portions, and a cylindrical body connected to one end of the metal foil. An internal lead rod provided with an electrode at the tip on the side protruding into the bulging portion and an external lead rod connected to the other end side of the metal foil and led out of the sealing tube part,
And a discharge medium sealed in a translucent container.

[0011] The surface of the cylindrical body and the separator inside the hold tube, as well as the sealing tube and the hold tube, which are close to a heat source such as a gas burner and ignited, are melted. While being fused with the glass of the shape and the separator, the glass melted and flowed is hermetically sealed so as to cover the molybdenum foil.

Since the cylindrical body and the separator having the internal lead rods inside the hold tube penetratingly held therein are held substantially on the central axis of the sealing tube portion, they do not enter a molten state during heating and are always in the melting process. As a result of being surrounded by the outer holding tube, its movement is small, and it is held substantially on the central axis of the sealing tube portion even after sealing.

Further, the present invention is applicable to high-pressure discharge lamps such as short arc metal halide lamps, ultra-high pressure mercury lamps and xenon lamps, and ultra-high pressure discharge lamps using a translucent vessel made of quartz glass.

A high pressure discharge lamp according to a second aspect of the present invention is characterized in that a portion of the sealed tube portion adjacent to the bulging portion has a larger diameter than an end portion of the sealed tube.

The sealing tube portion adjacent to the bulging portion has a large diameter because it is sealed via a cylindrical body having an internal lead rod penetrating and held therein, so that the internal lead rod can be securely held firmly. it can.

According to a third aspect of the present invention, in the high pressure discharge lamp, the cylindrical body through which the hold tube and the inner lead rod penetrate has a cylindrical structure in which an end face portion facing the bulging portion does not protrude into the bulging portion. Are not projected from the end face of the hold tube.

Although the sealing tube, the hold tube, and the tubular body are made of the same quartz glass, for example, if the inner tubular body protrudes from the end face of the hold tube, the frontmost boundary is formed. Occurrence of wedge-shaped cracks, which may be caused by thermal stress, may be observed at the site, and it is preferable that the relationship between the three end surfaces is lower toward the cylindrical body at the same position or at the center.

In the high-pressure discharge lamp according to the fourth aspect of the present invention, the external lead rod may have a length of 3 m in the hold tube in the sealed tube portion.
m or more.

The portion of the inner lead bar that is separated from the molybdenum foil connection portion is in the through hole of the cylindrical body and is not in close contact with the glass, but the outer lead bar side is embedded in the sealing tube. Although there is a case where the sealing tube portion closely adheres to the glass (strictly speaking, even if it is said that there is close contact, there is a gap due to a difference in thermal expansion coefficient between the two and it is not airtight.) It is preferable that the embedded size is 3 mm or more.
This is because when the embedded portion is shallow (less than 3 mm) at the time of cutter cutting of the unsealed surplus portion at the end of the sealing tube portion, the embedded portion peels off due to the impact at the time of cutting, and this causes molybdenum. May extend to foil.

According to a fifth aspect of the present invention, there is provided a light irradiation device,
A high-intensity discharge lamp according to any one of claims 1 to 4, which is provided facing the reflection mirror, and a lighting circuit for the discharge lamp.

The light irradiating device equipped with the discharge lamp having the functions described in claims 1 to 4 has high reliability as the device.

The light irradiating device according to the present invention means not only a device that irradiates visible light but also a device that emits light in a wide wavelength range from the ultraviolet region to the infrared region. It can be applied to light irradiation in many fields.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show an ultra-high pressure mercury lamp L as a high pressure discharge lamp according to the present invention. FIG. 1 is a front view with a part thereof omitted, and FIG. 2 is a cutaway view of a lamp end before sealing. FIG. 3 is a partial sectional front view, and FIG. 3 is a transverse sectional view taken along line AA in FIG.

In the drawing, reference numeral 1 denotes a substantially elliptical light-transmitting container made of quartz glass, and a bulging portion 2 forming a light emitting space in the center.
And sealing pipe portions 3 and 3 extending to both ends thereof. The introduction bodies 4 and 4 are sealed in the sealing pipe portions 3 and 3, respectively.

The introduction member 4 is provided with molybdenum foils 5M, 5M as metal foils on the upper and lower surfaces of the ends of an inner lead rod 5A serving as an electrode rod made of tungsten, molybdenum, or the like and an outer lead rod 5B made of molybdenum or the like.
And between the molybdenum foils 5M, 5M, a separator 6 made of rectangular flat quartz glass is used.
S is interposed. Reference numeral 6T denotes a quartz glass tubular body through which the internal lead rod 5A penetrates at the center, and 6H denotes a quartz glass hold tube provided over substantially the entire inner circumference of the sealing tube portion. Constitutes the introduction body 4.

7A is an anode electrode fixed to the tip of one internal lead rod 5A, and 7C is an anode electrode fixed to the other internal lead rod 5A.
A cathode electrode fixed to the tip of B, which is disposed facing each other. In addition, an inert gas such as mercury and argon is sealed as a discharge medium in the bulging portion 2 forming the light emitting space. In the figure, 2E is an exhaust pipe, 8
Reference numerals A and 8B denote bases joined to the sealing tube portions 3 and 3 via a heat-resistant adhesive, and reference numeral 8L denotes a cord.

The assembling of the introduction body 4 of the discharge lamp L is performed by first shaving the upper and lower surfaces of one end of the inner lead rod 5A and the outer lead rod 5B, and forming the flat part 5F having substantially the same thickness as the separator 6S. 5F is formed, and the anode electrode 7A (cathode electrode 7C) is fixed to the other end of the internal lead bar 5A. After passing the cylindrical body 6T made of quartz glass through the inner lead rod 5A, the inner lead rod 5A and the separator 6S are connected in series, and the molybdenum foils 5M, 5M are placed on the upper and lower flat portions 5F, 5F of the inner lead rod 5A. Are applied, welding electrodes are applied to the upper and lower molybdenum foils 5M, 5M, and the three members are welded. Next, molybdenum foil 5M, 5M
Is inserted into the space where the other end of the outer lead bar 5B comes into contact with the end face of the separator 6S, and the upper and lower molybdenum foils 5M, 5M are applied with welding electrodes and energized to weld the three members in the same manner as described above. .

Then, these components are housed in a hold tube 6H made of quartz glass, and the assembly of the introduction member 4 is completed. At this time, the outer diameter of the cylindrical body 6T and the four corners of the separator 6S having a rectangular cross section having a rectangular shape contact the inner wall of the hold tube 6H with a small gap because movement and inclination are reduced. Preferably, it is in the fitted state. Further, the inner lead rod 5 penetrating the cylindrical body 6T
A (5B) is also preferably in the fitted state.

The introduction members 4, 4 assembled in this manner are sealed pipe portions 3, 3 extending to both ends of the translucent container 1.
Inserted inside and sealed. This sealing work is performed on the translucent container 1.
In a horizontal state, the container 1 side (including the introducing body 4) is rotated, or the heating burner side is rotated or oscillated around the sealing tube portion 3 so as to be performed almost uniformly by relative movement. it can.

The sealing operation will be described in more detail. First, the introduction member 4 inserted into the sealing tube 3 is a cylindrical member 6T.
And the outer periphery and the corners of the separator 6S are
H is supported by contacting the inner wall. When the inside of the translucent container 1 is exhausted or heated in a low-pressure inert gas atmosphere from outside, the sealing tube portion 3 is heated.
The hold tube 6H, the cylindrical body 6T, and the separator 6S are softened and melted, and the sealed tube portion 3 in a negative pressure state is shrunk and reduced in diameter.

In this heating, the sealing tube portion 3 closest to the gas burner is heated at the highest temperature, and then the internal holding tube 6H is formed. 6T and the surface side of the separator 6S are also melted, and the glass of the sealing tube portion 3 and the holding tube 6H is turned into a cylindrical body 6T.
And the glass melted and flowed while being fused with the glass of the separator 6S.
M is wrapped so as to enclose it, and hermetically sealed.

Since the tubular body 6T is interposed near the bulging portion 2 of the sealing tube 3, a large-diameter portion 3L thicker than the interposed portion of the separator 6S is formed. The cross section of the sealing tube portion 3 is, for example, in the completed lamp L of FIG. 1, since the separator 6S having a flat cross section is used.
It has an elliptical shape whose horizontal diameter is larger than its vertical diameter.

At this time, the outer diameter of the hold tube 6H constituting the introduction body 4 and the inner diameter of the sealing tube portion 3 are close to each other, and the gap is small, and this is the contact state. Is preferred.

With the above-described structure of the introduction member 4, the inner lead rod 5A (5B) and the separator 6S are sealed while being held substantially on the central axis of the sealing tube 3, and a heat source such as a gas burner is used. The glass of the sealing tube portion 3 and the hold tube 6H, which is strongly ignited, melts well, and as shown in FIG. .. In FIG. 4 indicate the boundaries of the respective glass members after sealing is completed.

The inner lead bar 5A (5B) and the center of the separator 6S, which are held substantially on the center axis, are not in a molten state but are surrounded by a hold tube 6H which is always outside even in the melting process. As a result, the movement is small, and is maintained substantially on the central axis of the sealing tube portion 3 even after the sealing.

According to the observations made by the present inventors in the above, a quartz glass cylindrical body 6T through which the internal lead rod 5A of the introduction body 4 inserted into the sealing tube portion 3 penetrates, and a quartz glass As shown in FIG. 4, the relationship between the holding pipe 6H and the hold pipe 6H is such that both end faces facing the bulging portion 2 are closer to the end than the line cc which does not protrude into the bulging portion 2 and have a cylindrical shape. It is preferred that the 6T side is lower toward the cylindrical body 6T at an equal position or at the center where the 6T side does not protrude from the end face of the hold tube 6H.

Although the three members are made of the same quartz glass, for example, the inside of the cylindrical body 6T side is the hold tube 6H.
If it protrudes from the end face of the
The generation of wedge-shaped cracks, which may be caused by thermal stress, may be observed.

Thereafter, the interior of the vessel 1 is evacuated through an exhaust pipe 2A provided in the bulging portion 2 as usual, and a predetermined inert gas such as mercury and argon is filled therein to blow off the exhaust pipe 2E. . In addition, the unsealed surplus portion covering the external lead rods 5B at the distal ends of both the sealing tubes 3 is cut and removed with a cutter, and the external lead rods 5B extending from the distal ends of the sealing tubes 3 are removed. Connect a lead wire (not shown). Then, the bases 8A and 8B are joined to both the sealing tube parts 3 and 3 via a heat-resistant adhesive, and a lead wire (not shown) is connected to the bases 8A and 8B to complete the ultrahigh-pressure mercury lamp L. I do.

The molybdenum foil 5 of the inner lead rod 5A
The portion distant from the M, 5M connection portion is in the through hole of the cylindrical body 6T and is not strictly adhered to the glass. Similarly, the external lead rod 5B side is not strictly adhered to the glass of the sealing tube portion 3 in a state of being embedded in the sealing tube portion 3.

The dimension embedded in the sealing tube 3 on the side of the external lead rod 5B is preferably 3 mm or more. This is because, when the embedded portion is smaller than 3 mm, the embedded portion is peeled off by the impact at the time of cutting the unsealed surplus portion at the end of the sealing tube portion 3, and this causes molybdenum foil 5M. , 5M and leaks in the sealing tube.

Therefore, the inner diameter of the sealing tube portion 3 is
Although the diameter is relatively large due to the need to pass through A, the hold pipe 6H having an outer diameter close to the inner diameter is interposed over almost the entire inner circumference of the sealing pipe portion 3 so that the inside of the hold pipe 6H The cylindrical body 6T supporting the internal lead 5A to be disposed and the separator 6S having the molybdenum foils 5M, 5M can be prevented from moving during the sealing operation, and the opposing electrodes 7A, 7
B does not cause eccentricity, and the quality is improved without lowering of the luminous efficiency or light distribution characteristics or breakage of the airtight container 1 due to uneven discharge. In addition, at the time of the sealing operation, the integrated introducing member 4 may be inserted into the sealing tube portion 3 and heated, so that the production is easy and the molybdenum foil 5M is not subjected to excessive stress, so that cutting is performed. The yield can be improved and the productivity can be increased.

FIG. 5 is a schematic diagram showing an embodiment of a light irradiation device which is turned on by mounting the ultrahigh pressure mercury lamp L. This light irradiating device is a semiconductor exposure device 9, which switches an ultra-high pressure mercury lamp L provided on a reflecting mirror 91 to a power supply 9.
2. The lighting is performed via the lighting circuit 93. The irradiation light directly reflected from the ultra-high pressure mercury lamp L and reflected by the reflecting mirror 91 is reflected by the reflecting mirror 94 and enters the condenser lens 95. After being condensed by the condenser lens 95, the photoresist 98 passes through the reflection mirror 96 and the condenser lens 97,
Through the reduction projection lens 99 and the wafer 9
0 can be exposed.

The semiconductor exposure apparatus 9 having such a configuration can obtain high reliability as an apparatus since the quality of the lamp L is good.

Next, a specific example of the ultra-high pressure mercury lamp will be described.

Lamp rating: 1 kW (lamp voltage: 45 V, lamp current: 22 A) Elliptical hermetic container: length: about 50 mm, maximum outer diameter: about 39 mm, bulge part: wall thickness: about 2.7 mm, sealing tube (anode) Side) Length about 70mm, (Thickness before sealing about 2mm), Large diameter part outside diameter about 18mm, Mo foil sealing part outside diameter about 16mm x about 13mm, Mo foil thickness about 30μm, width about 6mm, long Approximately 47mm, about 5mm of which (one side) is superposed for connection with the lead rod (2 pieces used), Sealing tube (cathode side) Length about 70mm, (Thickness before sealing about 2mm ), Large diameter part outer diameter about 14mm, Mo foil sealing part outer diameter about 12.5mm x about 10mm, Mo foil thickness about 30μm, width about 6mm, length about 47mm, and about 5mm (one side) Superimposed for connection with the rod (use two), internal lead Rod (anode side) W rod outer diameter about 4.0mm, length about 31mm, (cathode side) W rod outer diameter about 3.0mm, length about 30.5mm, external lead rod (anode side) W rod outer diameter About 3.0 mm, length about 10 mm, (cathode side) W rod outer diameter about 3.0 mm, length about 10 mm, electrode (anode side) W Maximum outer diameter about 12 mm, length about 15.5 mm, (cathode Side) W Maximum outer diameter about 6.0mm, length about 14.5mm, distance between discharge electrodes about 3.0mm, total lamp length about 228mm, enclosure Hg about 1250mg, Ar about 600torr, the following before sealing each member Separator (anode side) thickness about 2.5 mm, width about 10 mm, length about 37 mm, (quartz glass) (cathode side) thickness about 2.5 mm, width about 8 mm, length about 37 mm , Cylindrical body (anode side) outer diameter about 10.5mm, wall thickness about 3m , (Quartz glass) length about 16mm, (cathode side) outer diameter about 8.5mm, wall thickness about 2.25mm, length about 16mm, hold tube (anode side) outer diameter about 13mm, wall thickness about 1mm, long Approx. 80 mm, (quartz glass) (cathode side) Outer diameter: approx. 11.5 mm, wall thickness: approx. 1 mm, length: approx. 80 mm, 30 products each of the present invention (using a hold tube) and conventional products (without a hold tube) When the lamp was manufactured, in the conventional product, the eccentricity of the molybdenum foil and the electrode was higher than a specified value in one lamp, but in the product of the present invention, no lamp caused an abnormality in the electrode and the sealing tube.

The present invention is not limited to the above embodiment. For example, the high-pressure discharge lamp is not limited to an ultra-high pressure mercury lamp, but may be a metal halide lamp in which a halide is sealed or a xenon lamp in which xenon gas is sealed at a high pressure.
The lamp may have an elliptical shape, a spherical shape, a straight tube shape, or the like, and the sealing may be performed using a mold.

In the above embodiment, molybdenum foil is used as the metal foil for sealing, but metal foil made of another material such as tungsten may be used. Further, the number of welding points for connecting the metal foil and the lead bar is not limited to two.

Further, the light irradiating apparatus is not limited to the embodiment shown in FIG. 5, but may be an illuminating apparatus in addition to photochemistry, semiconductor manufacturing, image related, etc., and may be applied to light irradiating in many fields. It is.

[0049]

According to the first aspect of the present invention, the eccentricity does not occur in the opposing electrodes, and the quality is improved without the deterioration of the luminous efficiency and the light distribution characteristic or the breakage of the airtight container due to the uneven discharge. In addition, at the time of the sealing operation, since the integrated introduction body may be inserted into the sealing tube portion and heated, it is easy to manufacture, and the molybdenum foil is not cut because no excessive stress is applied thereto. A high-pressure discharge lamp with improved quality and productivity, such as improved yield and improved productivity, can be provided.

According to the second aspect of the present invention, the internal lead rod can be reliably and firmly secured, and the electrode can be held on the central axis of the airtight container, so that the quality can be improved.

According to the third aspect of the present invention, no crack is generated at the boundary between the glasses, and the yield is improved.

According to the fourth aspect of the present invention, at the time of cutting the surplus portion of the tip portion of the sealing tube, the impact at the time of cutting causes peeling of the embedded portion of the external lead rod, which extends to the molybdenum foil and to the lamp. No leaks occur.

According to the fifth aspect of the present invention, a light irradiation device with improved reliability can be provided.

[Brief description of the drawings]

FIG. 1 is a partially omitted front view showing an embodiment of an ultra-high pressure mercury lamp of the present invention.

FIG. 2 is a partially sectional front view showing a state before sealing of a lamp end portion.

FIG. 3 is a cross-sectional view taken along line AA of FIG. 2;

FIG. 4 is a cross-sectional front view of a main part showing another embodiment of the present invention.

FIG. 5 is a schematic view showing an embodiment of the light irradiation device of the present invention.

FIG. 6 is a partial cross-sectional front view showing a state before sealing of a conventional lamp end portion.

FIG. 7 is a cross-sectional view taken along line AA of FIG. 6;

[Explanation of symbols]

 L: High pressure discharge lamp (ultra high pressure mercury lamp) 1: Translucent container 2: Swelling part 3: Sealing tube part 3L: Large diameter part 4: Introductory body 5A: Internal lead rod 5B: External lead rod 5M: Metal Foil (molybdenum foil) 6H: hold tube 6S: separator 6T: cylindrical body 7A: electrode (anode) 7C: electrode (cathode) 9: light irradiation device (semiconductor exposure device) 91: reflecting mirror 93: lighting circuit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tetsuro Wakayama 4-3-1 Higashi Shinagawa, Shinagawa-ku, Tokyo Toshiba Lighting & Technology Corporation

Claims (5)

[Claims] 1. A quartz glass translucent container having a bulging portion forming a light emitting space and sealing tube portions extending from both ends thereof; and quartz provided substantially over the entire inner circumference of the sealing tube portion. A glass hold pipe; a quartz glass tubular body provided near the bulging portion in the hold pipe; a quartz glass flat separator provided adjacent to the tubular body in the hold pipe; A pair of metal foils provided substantially in parallel along the upper and lower flat portions of the separator; an inner portion connected to one end of the metal foil and provided with an electrode at a tip of a side protruding into the bulging portion through the tubular body A lead rod; an external lead rod connected to the other end of the metal foil and led out of the sealing tube; and a discharge medium sealed in a translucent container. High pressure discharge lamp. 2. The high-pressure discharge lamp according to claim 1, wherein a portion of the sealed tube portion adjacent to the bulging portion has a larger diameter than an end portion of the sealed tube. 3. The tubular body through which the hold tube and the inner lead rod penetrate, is characterized in that the end face portion facing the bulge does not protrude into the bulge and the tubular body does not protrude from the end face of the hold tube. The high-pressure discharge lamp according to claim 1, wherein 4. The high-pressure discharge lamp according to claim 1, wherein the external lead rod is buried in a hold tube in the sealed tube portion by 3 mm or more. 5. A light irradiation device comprising: a reflecting mirror; a high-pressure discharge lamp according to claim 1 disposed facing the reflecting mirror; and a lighting circuit of the discharge lamp. apparatus.