JP2001210103A - Device for light-source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for a small sized light-source 3 comprising a high pressure-discharge lamp 1 and a reflector 2 as intended not to be susceptible to have the lamp 1 and the reflector 2 broken or the like. SOLUTION: The reflector 2 is constituted by using the material of the thermal expansion coefficient not more than 15×10-7/ deg.C on the portion being in touch with the light emitting part 100 of the lamp 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a light source device, such as a projector, which uses light emitted from a high-pressure discharge lamp.

[0002]

2. Description of the Related Art A high-pressure discharge lamp is used as a light source of a projector such as a liquid crystal projector. In order to brighten an image projected on a screen of the projector, the light source lamp is required to have higher luminance. In addition, since the size of the projector has been reduced, the light source device has also been required to be reduced in size.

[0003] For this reason, Japanese Patent No. 2829339 describes a small-sized and high-intensity light source lamp by increasing the pressure during operation in order to realize a compact and high-intensity light source lamp ( Conventional example).

[0004] In order to reduce the size of the light source device, it is conceivable to reduce the size of the reflector by reducing the focal length of the reflector.

[0005]

Although reducing the size of the reflecting mirror is effective in reducing the size of the light source device, it is affected by the heat emitted from the high-intensity light source lamp.
There is a possibility that a problem such as a breakage of the reflecting mirror or a bulging or breaking of the light source lamp may occur.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a light source device comprising a reflector and a light source lamp, in which the size of the light source device can be reduced, and a crack or the like of the reflector and the light source lamp can be reduced. .

[0007]

According to a first aspect of the present invention, there is provided a light source device comprising: a high-pressure discharge lamp having a light-emitting portion in which at least a pair of electrodes are sealed; The thermal expansion coefficient of the contacting part is 15 ×
A reflecting mirror made of a material having a temperature of 10 ⁻⁷ / ° C. or less.

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

The high-pressure discharge lamp only needs to have a light-emitting portion in which at least one pair of electrodes is sealed, and a mercury lamp, a metal halide lamp, or the like is acceptable. Further, the form of the high-pressure discharge lamp may be either a double-sealed structure in which sealing portions are present on both sides of the light-emitting portion, or a single-sealed structure having a sealing portion on only one side. Also, as the container for forming the high-pressure discharge lamp, it is permissible to use another translucent container having a low expansion coefficient such as quartz glass.

The light emitting portion of the high pressure discharge lamp is a portion having a discharge space of the high pressure discharge lamp, and encloses a pair of electrodes and a discharge medium. The shape of the light emitting section is cylindrical,
It may be spheroidal or spherical. It is also allowed to enclose an auxiliary electrode and the like in addition to the pair of electrodes. The discharge medium is selectively sealed with mercury, metal halide, rare gas, or the like.

The reflecting mirror has a function of projecting light generated from the high-pressure discharge lamp with a desired light distribution. Shapes for this purpose include shapes such as a spheroidal shape and a quadratic radiation curve shape. Further, the material constituting the reflecting mirror is made of a material having a coefficient of thermal expansion of 15 × 10 ⁻⁷ / ° C. or less at least at a portion where the light emitting portion of the high-pressure discharge lamp comes into contact. Examples of the material include crystallized glass, quartz glass, and Vycor glass. In addition, it is also possible to increase the reflection efficiency of the reflector and increase the light utilization rate by depositing a thin multilayer reflective film on the inner surface of the reflector which houses the lamp.

It is sufficient that a part of the light emitting portion of the high-pressure discharge lamp is in contact with the reflecting mirror. The partial contact may be a point contact, a line contact, a surface contact, or the like. The area and number of contact points are not regulated. The connection between the reflector and the high-pressure discharge lamp may be fixed mechanically using a jig or the like, or the high-pressure discharge lamp and the reflector may be fixed using a ceramic adhesive.

The light source device only needs to use a light distribution in a state where a high-pressure discharge lamp and a reflecting mirror are combined.
As a use, a general lighting device, a projector device, an automobile headlight device, and the like are allowed.

According to the first aspect of the present invention, even when the reflector of the light source device is downsized, problems such as breakage of the reflector due to heat generated from the high-pressure discharge lamp, swelling and rupture of the high-pressure discharge lamp are reduced. The light source device can be provided.

According to a second aspect of the present invention, there is provided the light source device according to the first aspect, wherein the reflecting mirror mainly uses crystallized glass.

The crystallized glass is obtained by processing a glass into a desired shape and heat-treating the glass to crystallize the glass, and preferably contains a β-spodumene solid solution or a β-eucryptite solid solution. Crystallized glass containing these is, for example, Li ₂ O, Al ₂ O ₃ , SiO ₂
It is a heat-resistant material obtained by heat-treating and crystallizing a low-expansion glass containing a component as a basic component. This crystallized glass has excellent heat resistance and a low coefficient of thermal expansion (4 to 15 ×
10 ⁻⁷ / ° C.), and by depositing a thin multilayer reflective film on the crystallized glass substrate, the material of the reflecting mirror suitable for the present invention can be obtained.

Further, crystallized glass is easier to process than glass having another coefficient of thermal expansion.

According to the second aspect of the present invention, by using crystallized glass for the reflecting mirror, the reflector can be easily processed into a desired shape, and the reflecting mirror can be reduced in size.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the light source device according to the present invention will be described with reference to FIG. FIG. 1 is a side sectional view of the light source device. In FIG. 1, reference numeral 1 denotes a high-pressure discharge lamp.
Reference numeral 10 denotes an airtight container made of quartz glass, and the light emitting portion 100 of the airtight container 10 has a substantially spheroid made of 2.5 mm thick quartz glass. The light emitting portion is formed so that the major axis is about 12.5 mm and the minor axis is about 10 mm.

Electrodes 11a and 11b are sealed at both ends of the airtight container 10, respectively. 11a is an anode, 11
b is a cathode. The structure of the anode 11a is a 12 mm long, 1.0 mm thick electrode shaft 11 made of tungsten.
The electrode coil 112 is formed by winding a tungsten wire having a wire diameter of 0.7 mm into a tightly wound four times. The structure of the cathode 11b is composed of an electrode shaft made of tungsten and having a length of 12 mm and a thickness of 1.0 mm. The distance between the electrodes 21a and 21b is 1.5 mm.

The pair of electrodes 11a and 11b are made of metal foil conductors 13a and 13b sealed in sealing portions 12a and 12b.
It is connected to the. The metal foil conductors 13a and 13b are molybdenum foils, having a width of 2.0 mm, a length of 17 mm, and a thickness of 2 mm.
It is 5 μm. One metal foil conductor 13a connected to the electrode 11a is connected to an external lead wire (not shown).
It is electrically connected to the base 14 attached to the end,
The other metal foil conductor 1 connected to the electrode 11b
3b is connected to the external lead wire 15. The external lead 15 is made of a molybdenum metal rod having a diameter of 0.8 mm.

In such an airtight container 10, for example, 55 mg of mercury is sealed, and 27 kPa of argon gas is sealed as a rare gas.
Is composed.

The reflecting mirror 2 is made of crystallized glass and has a spheroidal shape with a focal length of 6 mm. A reflection surface 21 made of a deposited film of TiO ₂ —SiO ₂ or the like having excellent reflection characteristics is provided on the inner surface of the curved surface of the reflection mirror. This reflector 2
The front light-emitting portion, for example, the opening has an opening diameter of about 60 mm and a length of 55 mm. A support cylinder 22 is formed at the top of the back of the reflecting mirror 2. The base 14 of the high-pressure discharge lamp 1 is fixed to the support cylinder 22 with an adhesive 23 such as insulating cement. Thereby, the high-pressure discharge lamp 1 is attached to the reflecting mirror 2 so as to be in contact with a part of the reflecting mirror 2.

The light source device 3 is constituted by the reflecting mirror 2 and the high-pressure discharge lamp 1 fixed to the reflecting mirror 2 as described above, and the base 14 and the external lead 15 are connected to the lighting means 31. The lighting means 31 applies a voltage at which the no-load voltage becomes approximately 280 V to the high-pressure discharge lamp 1. By applying such a voltage,
The high-pressure discharge lamp 1 is DC-lit and the lamp current is 3.8
A, lamp voltage is 65V, lamp power is 247W
Is lit.

A description will be given of the result of an experiment conducted to demonstrate the effects of the present invention for the light source device 3 having the above configuration.

First, by using the high-pressure discharge lamp 1 and the reflecting mirror 2 of the above embodiment, the shortest distance h (mm) between the spherical portion of the high-pressure discharge lamp 1 and the reflecting mirror is changed to light the high-pressure discharge lamp 1. Table 1 shows the results of comparison of the states of the high-pressure discharge lamp 1 when the lamps were used.

[0027]

[Table 1]

The above result indicates that the high pressure discharge lamp 1 has an abnormality within about 15 minutes after the high pressure discharge lamp 1 is turned on. This result is considered as follows. When the distance between the light emitting portion 100 of the high-pressure discharge lamp 1 and the reflecting mirror 2 is relatively large, the high-pressure discharge lamp 1 and the high-pressure discharge lamp 1
An air flow is generated between the reflecting mirrors 2 heated by the radiant heat, and the convection prevents an abnormal temperature, thereby causing an abnormal state such as breakage of the high-pressure discharge lamp 1. However, when this distance is shortened, the gap through which the air flows is reduced, and the air is heated by the mutual radiation rather than the cooling effect of the air flow. It is thought to lead to damage. Further, the further shortening of the distance and the contact between the high-pressure discharge lamp 1 and the reflecting mirror 2 means that the heat generated from the high-pressure discharge lamp 1 is directly transmitted to the reflecting mirror 2 by heat conduction, and the high-pressure discharge lamp 1 is heated to a high temperature. It is thought that can be suppressed.

Next, the material (particularly the coefficient of thermal expansion) of the reflecting mirror 2
A test was conducted on the occurrence of a defect in the reflector 2 due to the difference between the two. This test was also performed using the high-pressure lamp 1 of the present embodiment and the reflector 2 having the same shape. With the present embodiment,
This is a comparison with a case where only the material of the reflecting mirror 2 is changed as follows.

The results are shown in Table 2.

[0031]

[Table 2]

The above result indicates that an abnormality has occurred in the reflecting mirror 2 within about 15 minutes after the high-pressure discharge lamp 1 is turned on. Regarding this result, the heat generated by the high-pressure discharge lamp 1 causes the high-pressure discharge lamp 1 and the reflecting mirror 2 to expand.
When the reflector has a large coefficient of thermal expansion, such as borosilicate glass, the reflector 2 expands, and cracks occur in the portion of the reflector 2 that contacts the light emitting portion 100 of the high-pressure discharge lamp 1 in particular. It is considered something. Even in this case,
It was confirmed that the reflector made of a material having a coefficient of thermal expansion of 15 × 10 ⁻⁷ / ° C. or less did not cause abnormalities such as cracks.

A second embodiment of the present invention will be described with reference to FIG. In the present embodiment, a liquid crystal projector 30 is formed using the light source device 3 described above. That is, the liquid crystal projector 30 has the light source device 3 connected to the lighting means 31, the liquid crystal display panel 33 driven by the liquid crystal driving means 32, and the light emitted from the light source device 3 and passed through the liquid crystal display panel 33. An optical system 35 for projecting light onto a screen 34, that is, a mirror 36 and a lens 3
7, lighting means 31, light source device 3, liquid crystal driving means 32,
This is an example of a liquid crystal projector 30 including a housing 39 that accommodates a liquid crystal display panel 33 and an optical system 35 and has an opening 38 that projects light transmitted through the liquid crystal display panel 33 onto a screen 34.

[0034]

According to the light source device of the first aspect of the present invention, even when the reflector of the light source device is miniaturized, the reflector generated by the high-pressure discharge lamp is broken, and the high-pressure discharge lamp is swollen or ruptured. And the like can be reduced.

According to the second aspect of the present invention, by using crystallized glass for the reflector, the reflector can be easily processed into a desired shape, and the reflector can be made smaller.

[Brief description of the drawings]

FIG. 1 is a sectional view of an embodiment of a light source device according to the present invention.

FIG. 2 is a schematic sectional view of a projector using the light source device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... High pressure discharge lamp 100 ... High pressure discharge lamp light emitting part 2 ... Reflecting mirror 3 ... Light source device 30 ... Projector device 31 ... Lighting means

 ────────────────────────────────────────────────── ─── Continued from the front page (72) Inventor Tetsuo Otani 4-3-1 Higashishinagawa, Shinagawa-ku, Tokyo Toshiba Litec Co., Ltd. F-term (reference) 3K042 AA01 AB03 AC06 BA01 BB01 CC04 CC05

Claims (2)

[Claims] A high-pressure discharge lamp having at least a pair of electrodes sealed therein and having a light-emitting portion; a light-emitting portion of the high-pressure discharge lamp being in contact with the light-emitting portion;
A reflecting mirror made of a material having a temperature of 5 × 10 ⁻⁷ / ° C. or less. 2. The light source device according to claim 1, wherein the reflection mirror mainly uses crystallized glass.