JPH09185953A - High-pressure discharge lamp, lamp device, lighting device, projector, and liquid crystal projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively prevent the generation of shell-shaped cracks in a crush sealing part and enhance reliability in the sealing part. SOLUTION: Crush sealing edge parts 12a, 12b for sealing in airtightness electrode shafts 13c, 13d by crushing the both ends of a main body part 2, a bulb 12 whose tube wall load is 30W/cm<2> or more, and molybdenum foils 14a, 14b which are embedded in the crush sealing parts and weld the electrode shafts are arranged. When rated lamp input power is represented by WL (W), the temperature in a portion where is the outer surface of the crush sealing edge part 12a to which one surface of the molybdenum foil 14a is faced and locating in the shortest distance h (mm) from the electrode shaft 13c is represented by T ( deg.C), the width of the molybdenum foil 14a is represented by La (mm), and the thickness of the foil 14a is represented by Lb (μm), the following relations are satisfied. T<=800( deg.C), 8.0<=Lb/La<=15.0, 0.3×10<-2> <=h/WL<=1.0×10<-2> .

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 short arc type metal halide lamp and a lamp device, a lighting device, a lighting device, a projector and a liquid crystal projector using the lamp as a light source.

[0002]

2. Description of the Related Art Conventionally, metal halide lamps have been widely used mainly for sports lighting and the like due to their high color rendering properties and high efficiency. In particular, in recent years, a short arc type metal halide lamp having a short arc length is close to a point light source, and a large amount of light is obtained for the power.
That is, because of its high luminous efficiency, it is often used as a light source for OHP (overhead projector) or floodlighting.

FIG. 10 is a longitudinal sectional view showing a part of a conventional metal halide lamp 1 of this type. The lamp 1 is a direct current lighting type and an elliptic spherical shape of a bulb 2 which is an airtight container made of quartz glass. In the main body 2a, an appropriate amount of metal halide, mercury, and rare gas are enclosed together with the anode 3a and the cathode 3b.

The anode 3a and the cathode 3b have molybdenum foil 4 which is a conductor foil at the tips of the respective electrode shafts 3c and 3d.
It is fixed to each inner end portion of a and 4b by welding or the like. The molybdenum foils 4a and 4b are embedded in a pair of sealing end portions 2b and 2c formed by crushing (pinching) the long diameter both ends of the valve 2, and the molybdenum foils 4a and 4b are provided at their outer ends with a die. 5 and the outer lead wire 6 are electrically connected.

[0005]

However, in the conventional metal halide lamp 1 as described above, the sealing portion 2b on the side of the anode 3a, which has a particularly high temperature during lighting, is provided with the anode shaft 3c of the molybdenum foil 4a embedded therein. Shell-shaped cracks 7 may occur around the welded portion, leading to cracking.

That is, during lighting, the anode 3a generates heat and rises to a high temperature, and this heat is transmitted through the anode electrode shaft 3c to the molybdenum foil 4a on the anode 3a side and the sealing end portion 2 around it.
Heat is conducted to the quartz glass of a to expand together, and when the light is turned off, the temperature of the silica glass is lowered to shrink together.

However, the molybdenum foil 4a and the sealing portion 2 are
Since the coefficient of thermal expansion is slightly different from the quartz glass of a, thermal stress is generated in the quartz glass. Moreover, since this thermal stress increases due to repeated heat cycles of turning on and off the lamp, shell-like cracks (also referred to as rib cracks) 7 are generated as shown in FIG. 11, which may gradually expand and lead to cracks.

Therefore, an object of the present invention is to provide a high-pressure discharge lamp capable of effectively preventing the occurrence of shell-like cracks at the crushing pressure-stop end and improving the reliability of the sealing end. An object is to provide a lamp device, a lighting device projector, and a liquid crystal projector.

[0009]

According to the first aspect of the present invention,
A pair of electrodes that are arranged to face each other to generate a discharge; a main body containing the pair of electrodes and a discharge medium, and both ends of the main body are crushed and hermetically sealed, and each electrode shaft of the pair of electrodes An airtight container having a tube wall load of 30 W / cm ² or more, which is integrally formed with a crush-sealing end that hermetically seals one end of each of; and is embedded in each crush-sealing end of the airtight container. And a conductor foil for welding the electrode shaft, the rated lamp input power is WL (W), and one side of the conductor foil on the side where the electrode shaft is welded faces the outer surface of the crushed sealing end. When the temperature of the portion located at the shortest distance h (mm) from the electrode axis is T (° C), the foil width of the conductor foil is La (mm), and the foil thickness is Lb (μm), [Formula 3] is satisfied.

[0010]

(Equation 3)

Therefore, according to the present invention, the electrode shaft of the anode, which generates heat during lighting and rises to a high temperature, is formed on the outer surface of the sealing end portion at the shortest distance h (mm) from the welded portion welded to the conductor foil. Since the temperature T of the shortest point is set to 800 ° C or less,
It is possible to reduce the occurrence of shell-like cracks and improve the reliability of the sealing portion.

Further, the thickness Lb (μm) and the width (m
Since the ratio Lb / La with m) is also set within the range of 8 or more and 15 or less, it is possible to reduce the occurrence rate of foil breakage at the time of pinching (crushing) the sealing end and to form a shell shape. The occurrence rate of cracks can also be suppressed.

Further, the ratio h / W between the shortest distance h (mm) from the measuring point of the temperature T to the electrode axis and the rated lamp input power WL (W) is 0.3 × 10 ^-2 or more and 1.0. Since it is set within the range of × 10 ^-2 or less, it is possible to suppress the decrease in lamp efficiency while sufficiently ensuring the strength of the sealing portion.

The invention according to claim 2 is the invention according to claim 1, further comprising a pair of electrodes, an anode and a cathode, wherein the temperature T is crushed and sealed at a position located at a shortest distance h from the anode electrode axis. It is the temperature of the outer surface of the stop.

Therefore, according to the present invention, even when the invention described in claim 1 is applied to a high-voltage discharge lamp for direct current lighting, the same operational effect as the invention described in claim 1 can be obtained.

According to a third aspect of the present invention, an anode and a cathode which are arranged to face each other to generate a discharge; a main body containing the anode and the cathode and a discharge medium, and both ends of the main body are crushed and hermetically sealed. The tube wall load, which is integrally formed with the sealing end portion that hermetically seals one end portion of each of the anode and cathode electrode shafts,
An airtight container having a W / cm ² or more; a conductor foil embedded in each crushed and sealed end of the airtight container to weld an electrode shaft;
The diameter of the anode electrode shaft is φ, and the depth of the conductor foil, which is the shortest distance from the spherical outer surface extension of the airtight container body to the inner end of the conductor foil to which the anode electrode shaft is welded, is L
When c is set, the following [Equation 4] is satisfied.

[0017]

(4) 2.5 ≦ Lc / φ ≦ 6.5

Therefore, according to the present invention, the ratio of the conductor depth Lc (mm) to the electrode shaft diameter φ (mm) of the anode is 2.5 or more and 6.5 in high voltage discharge of direct current lighting.
Since it is set within the following range, it is possible to prevent the temperature of the welded portion between the anode electrode shaft and the conductor foil from rising excessively and causing the occurrence of shell-like cracks in the sealed end portion around the conductor foil. In addition, it is possible to effectively prevent a decrease in lamp efficiency due to an excessive decrease in temperature of the airtight container.

The invention according to claim 4 is the invention according to claims 1 to 3.
In the invention according to any one of the above items, the discharge medium is a metal halide.

Therefore, according to the present invention, even when the invention according to any one of claims 1 to 3 is applied to a rutal halide lamp in which a metal halide is enclosed as a discharge medium, the same effects as those of the invention are obtained. Can be played.

The invention according to claim 5 is the invention according to claims 1 to 4.
In the invention according to any one of the above items, the conductor foil is molybdenum foil.

Therefore, according to the present invention, even when the invention according to any one of claims 1 to 4 is applied to the high-pressure discharge lamp in which the conductor foil is a molybdenum foil, the same effects as those can be obtained. .

The invention according to claim 6 is the invention according to claims 1 to 5
A high pressure discharge lamp according to any one of the above;
A reflector that accommodates the lamp with its axis aligned with the optical axis, reflects the light emitted from this lamp, and projects it from the front opening.

The invention according to claim 7 is the invention according to claims 1 to 5.
A high pressure discharge lamp according to any one of the above 1; and a lighting circuit for supplying lamp power to a pair of electrodes of the high pressure discharge lamp for stable lighting.

The invention described in claim 8 includes the lighting device according to claim 7, an optical system for controlling light from a high-pressure discharge lamp of the lighting device to project the light on a screen, and the lighting device and the optical system. And a case having an opening formed to project the light projected from the optical system onto the screen.

According to a ninth aspect of the present invention, there is provided a lighting device according to the seventh aspect; a liquid crystal display panel driven by a liquid crystal driving device; and a screen through the liquid crystal display panel by controlling light from a high pressure discharge lamp of the lighting device. An optical system for projecting light onto the
The housing includes a lighting device, a liquid crystal driving device, a liquid crystal display panel, and an optical system, and a housing having an opening for projecting light projected through the liquid crystal display panel onto a screen.

Therefore, the lamp device according to claim 6, the lighting device according to claim 7, the projector according to claim 8 and the liquid crystal projector according to claim 9 are the high-pressure discharge lamp according to any one of claims 1 to 5. Therefore, it is possible to obtain the same effects as those described above.

[0028]

FIG. 1 is a block diagram showing an embodiment of the present invention.
This will be described with reference to FIG. 1 to 9, the same or corresponding parts are denoted by the same reference numerals.

FIG. 1 is a front view showing a longitudinal section of an essential part of a metal halide lamp according to a first embodiment of the present invention, and FIG. 2 is a sectional view taken along the line II--II of FIG. Illuminated short arc type metal halide lamp 11
Is, for example, an airtight container made of quartz glass and has a tube wall load of 3
Elliptical body 1 of valve 12 of 0 W / cm ² or more
2a and a pair of sealing ends 12b and 12c, which are formed by airtightly pinching the both ends in the major diameter direction, are integrally formed.

The valve body 12a has a pair of left and right anodes 13a and cathodes 13b in the drawing which are opposed to each other with a predetermined distance between the electrodes. A proper amount of mercury (Hg), argon (A
r) and other rare gases, and metal halides such as dyspium bromide and cesium iodide are enclosed in appropriate amounts.

Then, the anode 13a and the cathode 13b
The outer ends of the electrode shafts 13c and 13d are fixed to the inner ends of the pair of molybdenum foils 14a and 14b, which are hermetically embedded in the pair of sealing ends 12b and 12c, by welding or the like. In addition, reference numerals 12d and 12e in FIG.
When pinching a by pinching a in the diametrical direction, the anode electrode shaft 13c is strongly pushed into the molybdenum foil 14a side,
This is an escape for curving the molybdenum foil 14a to prevent the foil from breaking.

The outer ends of the molybdenum foils 14a and 14b are electrically connected to the base 15 and the outer lead wires 16 via lead wires (not shown). Base 1
5 is tightly fitted onto the outer circumference of one sealing end 12b, and a predetermined lamp voltage is applied between the anode 13a and the cathode 13b via the base 15 and the outer lead wire 16.

In the metal halide lamp 11, the rated lamp input power is WL (W), the width of the molybdenum 14a on the anode 13a side is La (mm), as shown in FIG.
The foil thickness is Lb (μm), and the sealing end portion 12 at the shortest point P, which is the shortest distance h (mm) away from the upper surface in the figure of the welded portion of the electrode shaft 13c of the anode 13a to be welded on the molybdenum foil 14a. When the temperature of the outer surface of (1) is T (° C.), the following [Equation 5] is satisfied.

[0034]

(Equation 5)

That is, since the temperature of the welded portion between the anode electrode shaft 13c and the molybdenum foil 14a rises to a high temperature when the lamp is turned on, this is a major cause of the occurrence of shell-like cracks at the sealing end 12b due to the heat cycle caused by blinking. I'm doing one. However, since this welded portion is buried in the sealed end portion 12b, the temperature cannot be measured directly. Therefore, the temperature T of the shortest point P from this weld is measured as an approximate value. As a result of various experiments, the temperature T of the shortest point P becomes lower as the shell temperature decreases as shown in FIG. 3 (A). The rate of occurrence of cracks is reduced. The occurrence rate of shell-like cracks in FIG. 3B indicates the occurrence rate of shell-like cracks when the lamp 11 is turned on for 5 minutes and then turned off for 1 minute 10,000 times.

Therefore, based on these various experiments and the experimental data thereof, as shown in the above [Equation 5], T ≦
It was found that by setting the temperature to 800 (° C.), it is possible to both suppress the occurrence of shell-like cracks and improve the lamp efficiency.

Further, the molybdenum foil 14a has a foil thickness Lb (μ
The mechanical strength of m) decreases as it becomes thinner, and the rate of occurrence of foil breakage due to the pressure applied during pinch of the sealing end 12b and the flow of the quartz glass around it increases.

Therefore, as shown in FIG. 4A, as the ratio Lb / La between the foil thickness Lb (μm) and the foil width La (mm) of the molybdenum foil 14a becomes smaller, the sealing end portion 12b becomes smaller.
It was found that the occurrence rate of foil breakage in which the molybdenum foil 14a is cut during the pinch sharply increases, while the incidence rate of shell-like cracks sharply increases as Lb / La increases. The occurrence rate of shell-like cracks in FIG. 4 (B) indicates the occurrence rate of shell-like cracks when the blinking of the lamp 11 is performed 5000 times.

Therefore, based on these experiments and the experimental data, as shown in the above [Equation 5], 8.0 ≦ Lb
By setting / La ≦ 15, molybdenum foil 14
It was found that it is possible to reduce both the occurrence rate of foil breakage during pinching of a and the occurrence rate of shell-like cracks.

The ratio of the lamp power to the shortest distance h (mm) from the welded portion of the molybdenum foil 14a and the anode electrode shaft 13c to the shortest point P on the outer surface of the nearest sealing portion 12a is as shown in FIG. Lighting time is 1000H as it gets lower
The damage rate at r rapidly increases, and the lamp efficiency decreases as the ratio increases.

Therefore, as shown in the above [Formula 5], 0.
It was found that by setting 3 × 10 ^-2 ≤h / W≤1.0 × 10 ^-2 , the reliability of the sealing end portion 12a can be improved and the lamp effect can be improved.

FIG. 6 is a vertical cross-sectional view of a main part of a metal halide lamp 11A according to a second embodiment of the present invention. This lamp 11A has a tube wall load of 30 W / cm ² or more,
It is a lamp that is lit by direct current, and is configured to satisfy the following formula (6) when the diameter of the anode electrode shaft 13c is φ (mm) and the foil depth is Lc (mm). Is characterized by.

[0043]

## EQU6 ## 2.5 ≦ Lc / φ ≦ 6.5

The foil depth Lc extends horizontally outward from the arcuate extension line α of the outer peripheral surface of the valve body 2a having an elliptic spherical shape, as shown by the broken line in FIG. 6, and is welded to the anode electrode shaft 13c. Shows the shortest distance to the inward inner end of the molybdenum foil 14a.

That is, as described above, the occurrence rate of shell-like cracks increases as the temperature of the welded portion between the anode electrode shaft 13c and the molybdenum foil 14 increases, and conversely, as the temperature decreases, the occurrence rate of shell-like cracks. Will also decrease, so
It is possible to lower the temperature by increasing the foil depth Lc, but the foil depth L
In order to increase c, it is necessary to reduce the electrode diameter φ in order to improve the sealing reliability.

On the other hand, if the foil depth Lc is increased, the sealing length of the electrode shaft 13c is increased correspondingly, so that the airtightness of the sealing portion on the anode side is reduced and the reliability is lowered. If the electrodes are made thin, the current density becomes high, the electrodes are broken, and the reliability is lowered. For this reason, the foil depth Lc
If the length is shortened, the weld temperature of the electrode shaft 13c and the conductor foil 14a rises, and if the electrode shaft 13 is made thick, the difference in the coefficient of thermal expansion between the quartz and the electrode shaft 13c becomes large at the time of sealing, and
Large cracks are generated around c, airtightness is also lowered, and reliability is lowered and lamp temperature is lowered due to excessive temperature reduction of the electrodes.

Therefore, the foil depth Lc (m
m) and the shaft diameter φ (mm) of the anode electrode shaft 13c, Lc / φ is variously changed, the lamp is turned on for 5 minutes and then turned off for 1 minute.
When an experiment for visually checking whether a shell-like crack has occurred is performed, the experimental data of FIG. 5C is obtained.

The metal halide lamp 1 shown in FIG.
An example of the size of 1A is as follows. That is, the diameter of the anode electrode shaft 13c is 1.1 mm, the foil depth Lc is 5.0 mm, the outer diameter φ0 of the valve body 2a is 14 mm, and the anode electrode 1
The diameter φk of 3a is 2.3 mm, and the length Ld from the tip of the anode electrode 13a to the sealing end of the anode electrode shaft 13c is 6.0 mm. Therefore, since Lc / φ is about 4.54, which is in the range of 2.5 to 6.5, the anode 1
No occurrence of shell-like cracks could be visually observed on the sealed end 12a on the 3 side.

FIG. 7 shows an example of a light projecting device 22 according to a third embodiment of the present invention. This is a case where, for example, 11 of the metal halide lamps 11 and 11A described above is inside the reduced diameter of a bowl-shaped reflector 21. The lamp device is concentrically mounted on the bottom. The reflector 21 is made of glass or metal in the shape of a bowl, and a reflecting surface 23 made of a vapor-deposited film such as TiO ₂ —SiO ₂ having excellent reflecting characteristics is formed on the inner surface of the rotating curved surface having the focal point position F. The reflector 21 has a front projection opening whose opening diameter is, for example, 90 to 130.
The bowl-shaped outer bottom portion is provided with a support tubular portion 24 protruding concentrically outward. The base 15 of the lamp 11 is fixed to the inside of the support cylinder portion 24 with an adhesive 25 such as insulating cement. Thus, the lamp 1 is attached to the reflector 21 such that the lamp axis Oa-Ob is substantially aligned with the central axis of the reflector 21, that is, the optical axis Oc-Od.

The lamp 11 has a pair of electrodes 13a and 1a.
The intermediate portion between 3b is arranged so as to substantially coincide with the focus position F of the reflector 21. An introduction hole 26 is formed in the reflector 21, and the outer lead 16 of the lamp 11 penetrates through the introduction hole 26 and is guided to the rear surface side. The tip of the outer lead 16 is a lighting device 27.
Is connected to one end of the lighting device 27, and the other end of the lighting device 27 is connected to the base 15 of the lamp 11 via another outer lead 28, so that required power is supplied from the lighting device 27 via the pair of outer leads 16 and 28. It is supplied stably to the pair of electrodes 13a and 13b and is lit.

Therefore, since the light projector 22 uses the metal halide lamp 11 as a light source,
The starting voltage can be reduced by the trigger wire 18, and the valve 12 can be prevented from cracking or breakage to improve safety.

FIG. 8 shows an example of a projector 31 according to the fourth embodiment of the present invention, which comprises, for example, 11 of the metal halide lamps 11 and 11A, and a pair of electrodes 13a of the lamp 11 is provided. , 13b is supplied with a predetermined AC power through the base 15 and the outer lead 16 for stable lighting, and the light from the metal halide lamp 11 and its reflecting mirror 32 is projected onto the screen 33. Optical system 34 and these lamps 1
1, a reflecting mirror 32, a lighting device 27, and a housing 35 that houses an optical system 34. The housing 35 has an opening 35 a for projecting light from the optical system 34 onto the screen 33.

The optical system 34 has a condenser lens 36 for condensing light from the lamp 11 and the reflecting mirror 32, a first plane mirror 37, a Fresnel lens 38, a second plane mirror 39, etc. The light from the mirror 32 is controlled to project the light from the opening 35a of the housing 35 onto the screen 33.

FIG. 9 shows an example of a liquid crystal projector 41 according to the fifth embodiment of the present invention, which is, for example, a color liquid crystal display panel 42 in front of the light projecting device 22 shown in FIG. The projection lens 43 is installed to project the image displayed on the liquid crystal display panel 42 onto the screen 44. Further, the light projecting device 22 including the lighting device 27, the liquid crystal display panel 42, and the liquid crystal drive device 45 for driving the liquid crystal display panel 42 are housed in a housing 46.

Therefore, this liquid crystal projector 41
Also has the above-mentioned metal halide lamp 11,
The same operation and effect as the lamp 11 can be obtained.

[0056]

As described above, according to the invention of claim 1 of the present application, the shortest distance h ( mm), the temperature T at the shortest point on the outer surface of the sealed part is 800
Since the temperature is not higher than 0 ° C, the occurrence of shell-like cracks can be reduced and the reliability of the sealing portion can be improved.

Further, the thickness Lb (μm) and the width (m
Since the ratio Lb / La with m) is also set within the range of 8 or more and 15 or less, the occurrence rate of foil breakage at the time of pinch (crushing) of the sealing portion can be reduced and the shell-like cracks can be reduced. It is also possible to suppress the occurrence rate of.

Further, the ratio h / W between the shortest distance h (mm) from the measuring point of the temperature T to the electrode axis and the rated lamp input power WL (W) is 0.3 × 10 ^-2 or more and 1.0. Since it is set within the range of × 10 ^-2 or less, it is possible to suppress the deterioration of the lamp reliability and the lamp efficiency.

According to the invention described in claim 2, even when the invention described in claim 1 is applied to a DC-lit high-pressure discharge lamp, the same operational effect as the invention described in claim 1 can be obtained.

According to the third aspect of the invention, the conductor depth Lc (mm) of the high pressure discharge lamp of the direct current lighting with the lamp current of 3.0 (A) or more and the electrode shaft diameter φ (mm) of the anode. Since the ratio between the anode electrode shaft and the conductor foil was excessively increased, the shell-like shape was formed in the sealing portion around the conductor foil because the ratio between the anode foil and the conductor foil was excessively increased. It is possible to prevent the generation of cracks, and it is possible to prevent the lamp efficiency from being lowered due to the excessive temperature decrease of the electrode and the electrode breakage due to the thinning of the anode electrode root.

According to the invention described in claim 4, even when the invention according to any one of claims 1 to 3 is applied to a rutal halide lamp in which a metal halide is enclosed as a discharge medium, these inventions are the same. The effect of can be achieved.

According to the invention described in claim 5, even when the invention according to any one of claims 1 to 4 is applied to a high pressure discharge lamp in which the conductor foil is a molybdenum foil, the same action and effect are obtained. be able to.

A lamp device according to claim 6, a lighting device according to claim 7, a projector according to claim 8, and a projector according to claim 9.
Since the described liquid crystal projector has the high-pressure discharge lamp according to any one of claims 1 to 5, it is possible to obtain the same effects as those of these.

[Brief description of the drawings]

FIG. 1 is a partial vertical cross-sectional view of a metal halide lamp according to a first embodiment of the present invention.

FIG. 2 is an end view of a cut along the line II-II in FIG.

FIG. 3 is a graph showing a relative relationship between the temperature T of the shortest point P shown in FIG. 2 and the incidence rate of shell-like cracks.

4A is a graph showing a relative relationship between Lb / La and foil break of the lamp shown in FIG. 1, and FIG. 4B is a graph showing a relative relationship between the Lb / La and the incidence of shell-like cracks. .

5A is a lighting time 1000 of the lamp shown in FIG.
A graph showing the relative relationship between the damage rate in Hr and h / w,
(B) is a graph showing the relative relationship between the lamp efficiency and h / w of the lamp shown in FIG. 1, and (C) is a graph showing the relationship between Lc / φ and the defect occurrence rate.

FIG. 6 is a partial vertical cross-sectional view of a rutal halide lamp according to a second embodiment of the present invention.

7 is a vertical cross-sectional view of an example of a light projecting device (lamp device) including the metal halide lamp shown in FIG.

8 is a schematic diagram showing an overall configuration of a projector including the metal halide lamp shown in FIG.

9 is a configuration diagram of a liquid crystal projector including the light projecting device shown in FIG.

FIG. 10 is a partial vertical cross-sectional view of a conventional DC lighting type metal halide lamp.

FIG. 11 is a partially enlarged view of FIG. 10;

[Explanation of symbols]

11, 11A DC lighting type short arc type metal halide lamp 12 Bulb 12a Elliptic spherical valve body 12b, 12c Valve sealing end 13a Anode 13b Cathode 13c, 13d Electrode shaft 14a, 14b Molybdenum foil 15 Base 16 Outer lead wire 21 Reflector 22 Projector 31 Projector 33 Screen 34 Optical system 41 Liquid crystal projector 42 Liquid crystal display panel 45 Liquid crystal drive device

 ────────────────────────────────────────────────── ─── Continued from the front page (72) Inventor Mamoru Furuya 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Toshiba Lighting & Technology Corporation

Claims (9)

[Claims] 1. A pair of electrodes arranged to face each other to generate a discharge; a main body containing the pair of electrodes and a discharge medium, and both ends of the main body are crushed and hermetically sealed, and An airtight container having a tube wall load of 30 W / cm ² or more, which is integrally formed with a crushing sealing end for hermetically sealing one end of each electrode shaft of an electrode; A conductor foil embedded in the end portion for welding the electrode shaft; and having a rated lamp input power WL (W) and one surface of the conductor foil on the side where the electrode shaft is welded face-to-face sealing The shortest distance h (m
When the temperature of the portion located at m) is T (° C), the foil width of the conductor foil is La (mm), and the foil thickness is Lb (μm),
A high pressure discharge lamp characterized in that it is configured so as to satisfy the following [Equation 1]. [Equation 1] 2. The high pressure according to claim 1, wherein the pair of electrodes is an anode and a cathode, and the temperature T is the temperature of the outer surface of the crushing and sealing portion at a position located at the shortest distance h from the anode electrode axis. Discharge lamp. 3. An anode and a cathode arranged to face each other to generate a discharge; a main body containing the anode and the cathode and a discharge medium, and both ends of the main body are crushed and hermetically sealed, and an anode is formed. An airtight container integrally forming one end of each electrode shaft of the cathode and a sealing end that hermetically seals the tube wall load of 30 W / cm ² or more; A conductor foil embedded in the portion for welding the electrode shaft, wherein the anode electrode shaft diameter is φ, and the anode electrode shaft is welded from the spherical outer surface extension line of the airtight container body. A high pressure discharge lamp characterized in that it is configured so as to satisfy the following expression (2), where Lc is the depth of the conductor foil, which is the shortest distance to the edge. (2) 2.5 ≦ Lc / φ ≦ 6.5 4. The high-pressure discharge lamp according to claim 1, wherein the discharge medium is a metal halide. 5. The high pressure discharge lamp according to claim 1, wherein the conductor foil is a molybdenum foil. 6. A high-pressure discharge lamp according to claim 1, wherein the lamp is housed with its lamp axis aligned with the optical axis, and the light emitted from this lamp is reflected. And a reflector for projecting light from a front opening. 7. The high-pressure discharge lamp according to claim 1, and a lighting circuit for supplying stable lamp lighting by supplying lamp power to a pair of electrodes of the high-pressure discharge lamp. Lighting device. 8. The lighting device according to claim 7, an optical system for controlling light from a high-pressure discharge lamp of the lighting device to project the light on a screen, and a housing for housing the lighting device and the optical system. And a housing having an opening for projecting the projected light onto a screen. 9. A lighting device according to claim 7, a liquid crystal display panel driven by a liquid crystal driving device, and an optical system for controlling light from a high-pressure discharge lamp of the lighting device to project light onto a screen through the liquid crystal display panel. And a housing that houses a lighting device, a liquid crystal driving device, a liquid crystal display panel, and an optical system, and has an opening formed to project light transmitted through the liquid crystal display panel onto a screen. LCD projector.