JPH11195402A - Light source device and projection display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form light with an excellent color ballance, in a light source device provided with a discharge lamp used as a light source such as a projection display device and a reflection mirror. SOLUTION: A discharge lamp 10 is provided with a radiation part 17 in which metal halide is filled. The radiation part 17 is provided with a glass sealing part 26 sealed after filling metal halide. The discharge lamp 10 is attached to a reflection mirror 21 so that this glass sealing part 26 may be positioned on a plane 20a, vertically intersected with a plane 27a which is level with a ventilating port 27 of the reflection mirror 21 and a tube axis 10a of an arc tube is formed as one side of the surface 20a. Accordingly, a cooling air lead from the ventilating 27, collides with the glass sealing part 26 and almost uniformly flows around the radiation part 17. Conclusively, it is implemented to cool the radiation part 17 almost uniformly, and a temperature distribution in the radiation part 17 is equalized, and the radiation part 17 is prevented from breaking by a thermal stress.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light source device having a lamp such as a metal halide lamp suitable for use as a light source of a projection display device. Further, the present invention relates to a projection display device incorporating the light source device.

[0002]

2. Description of the Related Art Discharge lamps such as metal halide lamps and xenon lamps are used as light sources for projection display devices and the like. In particular, metal halide lamps are widely used as light sources for projection display devices because they have better luminous efficiency, longer life, and better color rendering properties than other types of lamps. Generally, such discharge lamps are
It is mounted on a lamp housing together with a reflector, and is used as a unit type light source device.

FIG. 10 shows a schematic cross section of a light source device used as a light source of a projection display device. As shown in this figure, the light source device 200 is basically composed of a lamp housing 202, a reflecting mirror 201 attached and fixed thereto, and a discharge lamp 210 horizontally disposed at the center of a reflecting surface 203 of the reflecting mirror 201. It is a light source device of a horizontal lighting system configured in a typical manner. Arc tube 21 of discharge lamp 210
Reference numeral 5 includes a light emitting portion 217 having a substantially elliptical spherical shape, and seal portions 218 and 219 projecting horizontally from both sides. These seal portions 218, 219 have electrodes 216,
216 are sealed. A metal halide is sealed inside the arc tube 215.

The encapsulation of the metal halide is performed by the light emitting section 2
This is performed through a sealing tube formed at 17. That is, at the time of molding the arc tube 215, a portion of the encapsulation tube protruding from the outer periphery of the light emitting portion 217 is integrally molded, a metal halide is sealed inside the arc tube from outside through the encapsulation tube, and after encapsulation, the encapsulation tube is sealed. Is blown off to remove the sealing tube and seal the arc tube 215. Therefore,
In a discharge lamp such as a metal halide lamp in which a gas is sealed inside an arc tube, a glass sealing portion 226, which is a sealing mark of the sealing tube, remains in a state protruding from the outer peripheral surface of the lamp light emitting portion. .

[0005]

Here, as a light source of a projection display device, particularly a projection display device capable of projecting a color image, a light source having an excellent color balance is suitable. In other words, it is necessary to use, as the light source, the light source device 200 including the discharge lamp 210 that balances the emission spectra of red, green, and blue. The factor that determines the distribution of the emission spectrum of the lamp is the vapor pressure in the light emitting section 217, and the temperature that determines the vapor pressure is the temperature inside the arc tube 215 in the light emitting section 217. For this reason, in order to stabilize the distribution of the emission spectrum of the encapsulated metal, it is important to make the temperature inside the arc tube in the light emitting section uniform.

Therefore, an object of the present invention is to provide a light source device of a horizontal lighting system in which a light source device of a horizontal lighting system is generally used in consideration of a fact that a light source device of a horizontal lighting system is generally used as a light source of the projection display device. It is an object of the present invention to propose a light source device having a good color balance suitable for use as a light source device. Another object of the present invention is to propose a projection display device using the light source device as a light source.

[0007]

According to the present invention, there is provided a discharge lamp comprising: a discharge lamp; and a reflecting mirror which reflects light emitted from the discharge lamp and emits the light as substantially parallel light. The discharge lamp has a light emitting tube having a light emitting portion in which a metal compound gas is sealed, and a light source in which a sealing portion sealed after the metal compound gas is sealed protrudes from an outer peripheral surface of the light emitting portion. In the device, the reflecting mirror is provided with a ventilation port for guiding cooling air to the sealing portion,
The sealing portion is characterized in that the tube axis of the arc tube is one side, and is located on a plane that intersects substantially perpendicularly with a plane horizontal to the ventilation port.

By arranging the sealing portion as described above,
Since the cooling air flows evenly around the light emitting part,
The temperature inside the arc tube in the light emitting section can be made uniform. Therefore, according to the present invention, since the light emission state of the discharge lamp can be improved, a light source device having a good color balance and suitable for a projection display device can be realized. Further, in the light source device of the present invention, since the cooling air flows evenly around the light emitting unit, the thermal stress applied to the light emitting unit becomes uniform. Therefore, it is possible to prevent the light emitting unit from being broken by thermal stress.

[0009] In the above light source device, the sealing portion may include:
It is preferable that the light emitting tube is disposed at a position closer to the ventilation port side than the center of the arc tube. By arranging the sealing portion in this manner, the flow of the cooling air can be made more uniform, and the light emitting state of the discharge lamp can be further improved.

In the above light source device, a modulating means for modulating a light beam emitted from the light source device in accordance with image information, and a modulated light beam modulated by the modulating means is enlarged on a projection surface. It can be used as the light source of a projection display device having projection means for projecting.

In particular, color separation means for separating a light beam emitted from the light source device into at least two color light beams, and modulation for performing modulation corresponding to image information on the light beam of each color separated by the color separation means. Means for synthesizing modulated light fluxes of the respective colors after being modulated by the modulation means, and projection means for enlarging and projecting the synthesized light flux emitted from the synthesis means on a projection surface. Suitable for use as the light source of a projection type display device.

Since the above light source device has a good color balance as described above, if this light source device is used for a projection display device, it is possible to obtain a projected image with a good color balance. Further, in the light source device described above, it is possible to prevent the light emitting portion of the lamp from being damaged by the thermal stress as described above, so that it is possible to provide a projection type display device with high safety.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Light Source Device) A light source device to which the present invention is applied will be described below with reference to the drawings. FIG. 1 is a perspective view showing the appearance of the light source device of this embodiment. FIG.
Is a cross-sectional view taken along line II of FIG. 1B, and FIG. 4 is a view of the light source device 30 of the present example as viewed from the opening side of the reflecting mirror 21. As shown in these drawings, the light source device 20 includes a discharge lamp 10, a reflector 21 to which the discharge lamp 10 is attached, and a resin lamp housing 22 to which the reflector 21 is attached. This is a horizontal lighting type light source device.

FIG. 2 is a perspective view showing the appearance of the discharge lamp 10. As shown in FIG. The discharge lamp 10 includes an anode core bar 1 opposed to the anode core bar 1 spaced apart by a short arc length of, for example, about 1.5 mm.
1 and cathode core rods 12, molybdenum foils 13 and 14 which are foil bodies connected to ends of the core rods 11 and 12 not facing each other, and core rods 11 and 12 and molybdenum foils 13 and 12, respectively. 14 is a metal halide lamp including an arc tube 15 that covers the lamp 14.

Each of the core rods 11 and 12 has a diameter of, for example, 0.1 mm.
The tip of the anode core rod 11 is made to have a diameter of, for example, 1.8 mm to facilitate discharge from the cathode core rod 12, and a tungsten wire is attached to the tip side of the cathode core rod 12. A coil wound tightly is arranged.

Each of the molybdenum foils 13 and 14 is not limited, but has a thickness of, for example, 20 μm and a width of 1.5 mm. A nickel lead 16 is connected to the opposite end.

The light emitting tube 15 is made of quartz glass and has an elliptical spherical hollow light emitting portion 17. Each core rod 11,
Numerals 12 denote electrode seal portions 18 and 19 integrally formed on both sides of the light emitting portion 17, and are disposed on substantially the same axis.
1 and 12 and the molybdenum foils 13 and 1
4 is sealed.

The reflecting mirror 21 has a reflecting surface 23 having a substantially parabolic cross section, and a lamp mounting hole 24 is formed at the bottom center of the reflecting surface 23. In this mounting hole 24,
The portion of the base 25 of the lamp having the above configuration is inserted and fixed with a heat-resistant adhesive. Here, the discharge lamp 10 is mounted on the reflecting mirror 21 so that the tube axis 10 a is horizontal, and the tube axis 10 a coincides with the central axis of the reflection surface 23. Therefore, one seal portion of the lamp arc tube 15 is in a state of protruding horizontally from the reflection surface 23 toward the front. The reflecting mirror 21 has a light emitting unit 17.
Are provided with a pair of ventilation holes 27 for guiding cooling air.

Here, the light emitting portion 17 of the discharge lamp 10 is filled with a metal halide. Examples of the metal halide include dysprosium iodide, neodymium iodide, and cesium iodide. The light emitting unit 17 includes
Along with the metal halide, mercury as a buffer gas and argon as an auxiliary gas for starting are also enclosed.

The filling of these metal gases is performed through a sealing tube formed in the light emitting section 17. This sealed tube is
When the arc tube 15 is molded, the arc tube 15 is integrally molded with the light emitting portion 17, and the root portion thereof is blown after filling the metal gas. Therefore, the discharge lamp 10 incorporated in the light source device 20
, A glass sealing portion 26 as a sealing mark of the sealing tube 21 remains. The glass sealing portion 26 protrudes from the outer peripheral surface of the light emitting portion 17, and the thickness of the glass in this portion is larger than the thickness of the glass in other portions of the light emitting portion 17. Therefore, the temperature in the light emitting section 17 tends to be non-uniform near the glass sealing section 26.

As described above, the light source of the projection display device is
It is necessary that the emission spectra of the red, green, and blue colors be balanced, and the factor that determines the distribution of the emission spectrum of the discharge lamp 10 is the vapor pressure in the light emitting section 17. Is the temperature inside the light emitting section 17. In order to stabilize the emission of the encapsulated metal and improve the balance of the emission spectrum, it is necessary to make the temperature distribution in the light emitting section 17 uniform.

In this embodiment, as shown in FIG. 3, the glass sealing portion 26 has the tube axis 10a of the arc tube as one side and the reflecting mirror 21
Surface 2 that intersects substantially perpendicularly with the horizontal surface 27a of the ventilation opening 27
0a so that the discharge lamp 10 is
It is attached to. Therefore, as shown in FIG. 4, the cooling air guided from the ventilation holes 27 flows around the light emitting unit 17 almost uniformly by hitting the glass sealing unit 26. Therefore, the light emitting unit 17 can be cooled almost uniformly, and the temperature distribution in the light emitting unit 17 can be made uniform.

In the light source device 20 of this embodiment, the glass sealing portion 2
Since the position of No. 6 is defined as described above, the temperature of the coldest part is raised, the vapor pressure in the light emitting part 17 is increased, and the light emission of metal halides other than mercury can be promoted. The spectrum is improved. Therefore, the color balance of the light source unit using the metal halide lamp can be improved, and the brightness on the projection surface can be increased.

As can be seen from FIG. 2, in the light source device 20 of this embodiment, the glass sealing portion 26 is located at a position closer to the ventilation opening 27 side than the center of the light emitting portion 17. In the light source device 20 of the present example, the light emitting unit 17 is located on the bottom surface side of the reflecting surface 23 with respect to the ventilation opening 27 for guiding the cooling air to the light emitting unit 17. Therefore, if the glass sealing portion 26 is arranged at a position closer to the ventilation opening 27 side than the center of the light emitting portion 17, the flow of the cooling air is not hindered. Therefore, the light emitting unit 17 can be cooled more uniformly, and the temperature distribution in the light emitting unit 17 can be further uniformed.

In the light source device 20 of this embodiment, the discharge lamp 10 may be another discharge lamp such as a xenon lamp. In addition, the lighting drive method of the discharge lamp 10 includes an AC drive according to the type of drive current applied between the electrodes.
Although an (AC) drive system and a DC (DC) drive system are known, the light source device 20 of this example may be of any type.

(Projection display device) Light source device 2 having the above configuration
An example of a projection display device provided with 0 will be described. This projection display device converts a light beam emitted from the light source device 20 into red,
The light beams are separated into three color light beams of green, blue, and are modulated according to video information through a light valve composed of a liquid crystal panel, and the modulated light beams of the respective colors are recombined and projected. It is of a type that is enlarged and displayed on a projection surface via a lens.

FIG. 5 shows the appearance of the projection display device of this embodiment. The projection display device 1 of this example has an outer case 2 having a rectangular parallelepiped shape. The outer case 2 basically includes an upper case 3, a lower case 4, and a front case 5 defining the front of the apparatus.
The front end portion of the projection lens unit 6 projects from the center of the front case 5.

FIG. 6 shows the arrangement of each component inside the outer case 2 of the projection display device 1, and FIG.
Shows a cross section taken along line II-II in FIG. As shown in these figures, a power supply unit 7 is disposed at the rear end side inside the outer case 2. A light source device 20 is arranged at a position adjacent to the power supply unit 7 on the front side of the device. On the front side of the light source device 20, an optical unit 9 capable of receiving a light beam emitted from the light source device 20 substantially along the optical axis is arranged. The base end side of the projection lens unit 6 is located at the front center of the optical unit 9. On the other hand, on the side of the optical unit 9, an interface board 111 on which an input / output interface circuit is mounted is disposed toward the front-rear direction of the apparatus. 112 are arranged. Further, a control board 113 for device drive control is disposed above the light source device 20 and the optical unit 9. Speakers 11 are provided at the left and right corners of the front end of the device, respectively.
4R and 114L are arranged. A cooling intake fan 115A is arranged at the center on the upper surface side of the optical unit 9, and a circulation fan 115B for forming a cooling circulation flow is arranged at the center on the bottom surface side of the optical unit 9. Also,
An exhaust fan 1 is provided on the side of the light source device 20, which is the back side.
16 are arranged. An auxiliary cooling fan 117 for sucking cooling airflow from the intake fan 115A into the power supply unit 7 is disposed at a position facing the ends of the substrates 111 and 112 in the power supply unit 7.

FIG. 8 shows the optical unit 9 and the projection lens unit 6 taken out. As shown in this figure, the optical unit 9 includes a color combining prism 910
Optical elements other than the above are sandwiched and held between upper and lower light guides 901 and 902 from above and below. These upper light guide 901 and lower light guide 902
Are fixed to the upper case 3 and the lower case 4 by fixing screws, respectively. The upper and lower light guide plates 901 and 902 are similarly fixed to the color combining prism 910 side by fixing screws.
The color combining prism 910 is fixed to the back side of the thick head plate 903, which is a die-cast plate, with fixing screws. On the front surface of the head plate 903, the base end side of the projection lens unit 6 is similarly fixed by fixing screws.

FIG. 9 shows a schematic configuration of an optical system incorporated in the projection display apparatus 1 of the present embodiment. The optical system of the projection display device 1 of the present embodiment includes the light source device 20 described above.
And a uniform illumination optical system 923. And
The projection display 1 includes a color separation optical system 924 as a color separation unit that separates the light beam W emitted from the uniform illumination optical system 923 into red (R), green (G), and blue (B), and each color. Three light valves 925R, 925G, 925B as modulating means for modulating the light beams R, G, B, a color synthesizing prism 910 as color synthesizing means for re-synthesizing the modulated color light beam, and a synthesized light beam Is provided on the surface of the projection surface 100 with a projection lens unit 6 as projection means. Further, the blue light flux B is transmitted to the corresponding light valve 9.
A light guide system 927 for guiding to the light guide 25B is also provided.

The uniform illumination optical system 923 includes two lens plates 921 and 922 and a reflection mirror 931. The two lens plates 921 and 922 are arranged so as to be orthogonal to each other with the reflection mirror 931 interposed therebetween. Uniform illumination optical system 923
The two lens plates 921 and 922 each include a plurality of rectangular lenses arranged in a matrix. The light flux emitted from the light source device 20 is transmitted to the first lens plate 921.
Are divided into a plurality of partial light beams by the rectangular lens. These partial luminous fluxes are divided into three light valves 925R and 925 by the rectangular lens of the second lens plate 922.
G, superimposed near 925B. Therefore, by using the uniform illumination optical system 923, even when the light source device 20 has an uneven illuminance distribution
The two light valves 925R, 925G, and 925B can be illuminated with uniform illumination light.

Each color separation optical system 924 includes a blue-green reflecting dichroic mirror 941, a green reflecting dichroic mirror 942, and a reflecting mirror 943. First, in the blue-green reflecting dichroic mirror 941, the blue light beam B and the green light beam G included in the light beam W are reflected at right angles, and head toward the green reflecting dichroic mirror 942. The red light beam R passes through the mirror 941, is reflected at a right angle by the rear reflection mirror 943, and is emitted from the emission unit 944 of the red light beam R to the prism unit 910 side.

Next, a green reflecting dichroic mirror 942
Of the blue and green light fluxes B and G reflected by the blue-green reflection dichroic mirror 941,
Only the green light beam G is reflected at a right angle, and is emitted from the emission unit 945 of the green light beam G to the color combining optical system side. The blue light flux B that has passed through the green reflection dichroic mirror 942 is emitted from the emission section 946 of the blue light flux B to the light guide system 927 side. In this example, the emission portions 944 and 94 of the color light beams in the color separation optical system 924 from the emission portion of the light beam W of the uniform illumination optical element.
The distances to 5,946 are set to be substantially equal.

The red and green luminous flux R of the color separation optical system 924,
Condensing lenses 951 and 952 are arranged on the emission sides of the G emission sections 944 and 945, respectively. Therefore,
The red and green luminous fluxes R and G emitted from the respective emission sections are incident on these condenser lenses 951 and 952 and are parallelized.

The red and green luminous fluxes R and G thus collimated enter the light valves 925R and 925G and are modulated to add image information corresponding to each color light. That is, these light valves are switching-controlled by drive means (not shown) in accordance with the image information, whereby the modulation of each color light passing therethrough is performed. As such a driving means, a known means can be used as it is. On the other hand, the blue light flux B is guided to the corresponding light valve 925B via the light guide system 927, where
Similarly, modulation is performed according to the image information. Note that the light valves 925R, 925G, and 925B of this example include an incident-side polarizing plate 960R, 960B, and 960G, an outgoing-side polarizing plate 961R, 961G, and 961B, and liquid crystal panels 962R, 962G, and 962B disposed therebetween. A liquid crystal light valve comprising: Liquid crystal panels 9262R, 9
As 62G and 962B, for example, polysilicon TF
An element using T as a switching element can be employed.

The light guide system 927 is a light emitting section 94 for the blue light flux B.
No. 6, a condenser lens 954 disposed on the exit side, an incident-side reflection mirror 971, an exit-side reflection mirror 972, an intermediate lens 973 disposed between these reflection mirrors, and a front side of the light valve 925B. And a condenser lens 953. The blue light beam B emitted from the condenser lens 946 is transmitted through the light guide system 927 to the light valve 95.
It is guided to 2B and modulated. The optical path length of each color light beam, that is, from the emission portion of the light beam W to each liquid crystal panel 962R, 962
G, the distance to 962B is the longest for the blue luminous flux B,
Therefore, the light amount loss of the blue light flux is the largest. However, by interposing the light guide system 927, the loss of light amount can be suppressed.

Each light valve 925R, 925G, 92
The color light fluxes R, G, and B modulated through 5B are incident on a color combining prism 910, where they are combined. The light combined by the color combining prism 910 is enlarged and projected through the projection lens unit 6 onto the surface of the projection surface 10 at a predetermined position.

The projection display device 1 of the present embodiment having the above-described configuration includes a light source device 20 to which the present invention is applied as a light source. The sealing portion 26 of the light source device 20
As described above, the tube axis 10a of the arc tube 15 has one side, and is located on the surface 20a that intersects the surface 27a that is horizontal to the ventilation port 27 almost perpendicularly. Therefore, since the light emitted from the light source device 20 has a good color balance, the projection type display device 1 including the light source device 20 can form an image with a good color balance on the projection surface.

(Other Embodiments) In the above embodiment, an example in which the light source device according to the above embodiment is applied to a transmission type projection display device has been described. However, the light source device according to the above embodiment is a reflection type light source device. The present invention can be applied to a projection display device. Here, “transmission type” means that a light valve such as a liquid crystal light valve transmits light, and “reflection type” means that the light valve transmits light. Means In the reflection type projection display device, the color combining prism is used as color light separating means for separating light emitted from the light source into light of three colors of red, green, and blue, and modulated light of three colors. Are recombined and used as a color light combining unit that emits light in the same direction. Even when the present invention is applied to a reflection type projection display device, almost the same effects as those of a transmission type projection display device can be obtained. The light valve is not limited to the liquid crystal light valve, and may be, for example, a light valve using a micro mirror.

Further, as the projection type display device, a front projection type display device for projecting an image from the direction of observing the projection surface, and a rear projection type display device for projecting an image from the side opposite to the direction of observing the projection surface. However, the light source devices according to the above embodiments can be applied to any of them.

[0041]

As described above, according to the present invention,
The light emitting state of the discharge lamp can be improved, and a light source device with good color balance can be obtained. Further, it is possible to realize a projection display device capable of forming an image with good color balance on a projection surface. In addition, a highly safe light source device and a projection display device can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a light source device to which the present invention is applied.

FIG. 2 is a perspective view showing a discharge lamp of the light source device according to the embodiment of the present invention.

FIG. 3 is a cross-sectional view taken along line II of FIG.

FIG. 4 is a view of the light source device of FIG. 1 as viewed from an opening side of a reflecting mirror.

FIG. 5 is a diagram showing an external shape of a projection display device including the light source device shown in FIG.

6 is a schematic plan view showing the internal structure of the projection display device shown in FIG.

FIG. 7 is a schematic cross-sectional configuration diagram taken along line II-II of FIG.

FIG. 8 is a schematic plan view showing the optical unit and the projection lens unit.

FIG. 9 is a schematic configuration diagram showing an optical system.

FIG. 10 is a schematic cross-sectional configuration diagram of a conventional light source device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Projection display apparatus 2 Exterior case 3 Upper case 4 Lower case 5 Front case 6 Projection lens unit (projection means) 7 Power supply unit 9 Optical unit 10 Discharge lamp 11 Anode core rod 12 Cathode core rod 13, 14 Molybdenum foil 15 Arc tube DESCRIPTION OF SYMBOLS 16 Lead wire 17 Light emitting part 18, 19 Electrode seal part 20 Light source device 21 Reflector 22 Lamp housing 23 Reflecting surface 24 Lamp mounting hole 25 Base 26 Glass sealing part 27 Ventilation opening 100 Projection surface 111 Interface substrate 112 Video substrate 113 Control substrate 114R, 114L Speaker 115A Intake fan 115B Circulation fan 116 Exhaust fan 117 Auxiliary cooling fan 200 Light source device 201 Reflecting mirror 202 Lamp housing 203 Reflecting surface 210 Discharge lamp 215 Arc tube 21 Light emitting unit 218, 219 Sealing unit 216 Electrode 226 Glass sealing unit 901, 902 Light guide 903 Head plate 910 Color combining prism (color combining unit) 921, 922 Lens plate 923 Uniform illumination optical system 924 Color separation optical system (color separation unit) ) 925R, 925G, 925B Light valve (modulation means) 927 Light guide system 931 Reflection mirror 941 Blue-green reflection dichroic mirror 942 Green reflection dichroic mirror 943 Reflection mirror 944, 945, 946 Emission section 951, 952, 953, 954 Condensing lens 960R, 960G, 960B Incident-side polarizing plate 961R, 961G, 961B Outgoing-side polarizing plate 962R, 962G, 962B Liquid crystal panel 971 Incident-side reflecting mirror 972 Outgoing-side reflecting mirror 973 Intermediate lens

Claims (6)

[Claims] 1. A discharge lamp comprising: a discharge lamp; and a reflecting mirror that reflects light emitted from the discharge lamp and emits the light as substantially parallel light. The discharge lamp includes a light emitting unit in which a metal compound gas is sealed. A light emitting device having a light emitting tube, wherein a sealing portion sealed after sealing the metal compound gas protrudes from an outer peripheral surface of the light emitting portion. A ventilation port for guiding wind is provided, and the sealing portion has a tube axis of the arc tube as one side, and is located on a surface substantially perpendicular to a horizontal surface of the ventilation port. Light source device. 2. The light source device according to claim 1, wherein the sealing portion is arranged at a position closer to the ventilation port side than a center of the arc tube. A light source device; a modulating means for modulating a light beam emitted from the light source device in accordance with image information; and a modulated light beam modulated by the modulating means on a projection surface. A projection type display device having a projection unit for enlarging and projecting, wherein the light source device includes: a discharge lamp; and a reflecting mirror that reflects light emitted from the discharge lamp and emits the light as substantially parallel light. The lamp has a light emitting tube having a light emitting portion in which a metal compound gas is sealed, and a sealing portion sealed after the metal compound gas is sealed protrudes from an outer peripheral surface of the light emitting portion; The reflector has a ventilation opening for guiding cooling air to the sealing portion. The sealing portion has a tube axis of the arc tube as one side, and is substantially perpendicular to a plane horizontal to the ventilation opening. Characterized by being located on a plane that intersects Copy-type display device. 4. The projection display according to claim 2, wherein the sealing portion is arranged at a position closer to the ventilation port side than a center of the arc tube. apparatus. 5. A light source device, a color separation unit that separates a light beam emitted from the light source device into at least two color light beams, and a light beam of each color separated by the color separation unit corresponding to image information. A modulating means for performing the modulation, a synthesizing means for synthesizing the modulated luminous flux of each color after being modulated by the modulating means, and a projection means for enlarging and projecting the synthesized luminous flux emitted from the synthesizing means on a projection surface. Wherein the light source device has a discharge lamp, and a reflecting mirror that reflects light emitted from the discharge lamp and emits the light as substantially parallel light, wherein the discharge lamp is a metal compound gas. A light-emitting tube provided with a light-emitting portion in which is sealed, a sealing portion sealed after the metal compound gas is sealed protrudes from an outer peripheral surface of the light-emitting portion, and the reflecting mirror includes: In the sealing part A ventilation port for guiding wind is provided, and the sealing portion has a tube axis of the arc tube as one side, and is located on a surface substantially perpendicular to a plane horizontal to the ventilation port. Projection type display device. 6. The projection display according to claim 5, wherein the sealing portion is disposed at a position closer to the ventilation port side than a center of the arc tube. apparatus.