JP2002260437A - Light source unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light source unit that can efficiently cool heat generated by a light source lamp even when using a mall and bright light source lamp as the light source. SOLUTION: The first front cover 21 is set in the front end of a concave reflector 2, the second front cover 22 is set in the front side of the first front cover 21 leaving a prescribed spacing. As an air intake 8 taking in air from the outside is set between the first front cover 21 and the second front cover 22, and an air inlet 21a allowing air to flow in the inside of the concave reflector 2 in the first front cover 21, the front edge of the concave reflector 2 is covered with the second front cover 22. Therefore, surrounding members can be prevented from being damaged by the fragment scattering when an arc tube 100 burst, and air can be allowed to flow in the inside of concave reflector 2 from the air intake 8 through the air inlet 21a, so that cooling of the inside of the concave reflector 2 is possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light source unit having a light source such as a discharge lamp and a reflector for reflecting light emitted from the light source in a predetermined direction, and more particularly to a short arc type mercury lamp and metal halide. The present invention relates to a light source unit mainly used for a liquid crystal projector or the like using a lamp or the like as a light source.

[0002]

2. Description of the Related Art Optical means used in a projection device such as a liquid crystal display device for displaying a desired image on an irradiation surface such as a screen has a uniform illuminance of light projected on the irradiation surface over the entire irradiation surface. In order to achieve this, a light source unit including a set of a light source that emits light having a desired luminance, a concave reflecting mirror that reflects light emitted from the light source in a uniform and uniform direction, and the like is used.

The light source used in the light source unit includes:
For example, a columnar discharge lamp such as a metal halide lamp and an ultra-high pressure mercury lamp is used.

[0004] A concave reflector for irradiating light from a light source in a certain direction usually has a cylindrical shape whose one end surface from which light is emitted is open, and an end facing the open end surface. The part is formed in a hemispherical shape, and is provided with a neck for attaching a discharge lamp serving as a light source. The discharge lamp is
It is arranged along the axis of the concave reflector, and one end of the discharge lamp is supported in the neck. The inner diameter of the neck is approximately the same as the diameter of the discharge lamp. The light emitted from the light source is reflected in a certain direction by the concave reflecting mirror, is emitted from an end face opening serving as an emitting surface of the concave reflecting mirror, and is then illuminated on the screen by various optical lenses such as an integrator lens. Is adjusted so as to be uniform, and the liquid crystal surface or the like is irradiated.

When a metal halide lamp having a short arc type arc tube is used as the light source of the light source unit, the pressure in the arc tube at the time of lighting is about 20 to
When it reaches about 150 atm and the arc tube is deteriorated, there is a possibility that the arc tube will burst. When the arc tube ruptures, the ruptured arc tube fragments may damage the inner peripheral surface of the concave reflector close to the arc tube, and furthermore, the optics disposed on the exit side of the concave reflector may be damaged. Debris may also scatter to peripheral components such as lenses, damaging these components.

In order to prevent damage to peripheral members due to such rupture of the arc tube, for example, Japanese Patent Laid-Open No. 25106/1993
Japanese Patent Application Laid-Open No. 4 (1999) -175 discloses a light source unit in which a transparent member such as a front glass is provided on the light emitting side of the concave reflecting mirror, and the inside of the concave reflecting mirror is sealed.

On the other hand, in the arc tube as a light source used in the above-mentioned light source unit, the temperature at the front end near the opening of the concave reflecting mirror tends to be particularly high, and the temperature of the arc tube becomes higher than a predetermined temperature. May cause devitrification in the arc tube. Further, when the temperature of the arc tube becomes high, the metal foil sealed in the sealing portions provided at both ends of the arc tube may be oxidized and expanded, and the metal foil may be broken.

[0008] In addition, when the concave reflecting mirror is sealed by the front glass as described above, the temperature of the inner peripheral surface serving as the mirror surface of the concave reflecting mirror becomes unnecessarily high, so that the concave reflecting mirror is formed on the inner peripheral surface. May exceed the heat resistant temperature of the deposited film, or
A large temperature difference occurs between the inner surface and the outer surface of the concave reflecting mirror, and the deposited film may be thermally deteriorated to cause cracks and the like, and further, heat may cause a large crack on the inner peripheral surface.

In order to prevent the arc tube and the concave reflecting mirror from being damaged by heat, an opening is formed in a front glass provided on the front surface of the concave reflecting mirror, and one sealing portion of the arc tube is formed from the opening. Japanese Patent Application Laid-Open No. 10-294013 discloses a light source unit that cools the arc tube by projecting a part of the light source.

[0010]

In recent years, a light source unit used in a projection type image display device such as a liquid crystal projector has been reduced in size and increased in brightness, and an arc tube and a concave reflecting mirror near the arc tube have been developed. May become very hot.

However, the above-mentioned Japanese Patent Application Laid-Open No. 10-294013
The light source unit described in the above publication is effective in cooling the sealing portion protruding from the opening formed in the front glass of the concave reflecting mirror, but the inside of the concave reflecting mirror becomes abnormally high in temperature. In addition, there is a problem that the arc tube portion and the concave reflecting mirror which are sealed in the front glass cannot be sufficiently cooled.

SUMMARY OF THE INVENTION The present invention has been made to solve such a problem, and an object of the present invention is to provide a small-sized light-brightness light source lamp as a light source. To provide a light source unit capable of efficiently cooling the light source.

[0013]

In order to solve the above-mentioned problems, a light source unit according to the present invention comprises a light source, a front end face opened as a light emitting face, and a rear end face opposed to the light emitting face having a concave reflecting face. And a concave reflecting mirror to which the light source is fixed at the rear end, a first front cover provided at the front end of the concave reflecting mirror so as to cover the light emitting surface of the concave reflecting mirror, A second front cover provided at a front end of the concave reflecting mirror at a predetermined interval in front of the first front cover, and the first front cover at a front end of the concave reflecting mirror; An air inlet for taking in air from the outside is provided between the second front cover and an air inlet for flowing air into the concave reflecting mirror is provided at a predetermined position of the first front cover. It is characterized by having.

In the light source unit of the present invention, it is preferable that an air outlet for discharging air to the outside of the concave reflecting mirror is formed at a rear side of the concave reflecting mirror.

In the light source unit of the present invention, it is preferable that an air inlet for taking in air from outside is formed behind the first front cover at a front end of the concave reflecting mirror.

In the light source unit of the present invention, it is preferable that a part of the light source protrudes forward through an air outlet formed in the first front cover.

In the light source unit of the present invention, a guide member for guiding the flow of air in the direction of the air inlet, opposite to the air inlet formed in the first front cover, on the second front cover. Is preferably provided.

[0018]

Embodiment 1 Hereinafter, a light source unit 1 according to Embodiment 1 of the present invention will be described with reference to the drawings.

FIG. 1 is a sectional view showing a schematic configuration of a light source unit 1 according to Embodiment 1 of the present invention.

The light source unit 1 has a concave reflecting mirror 2 for irradiating light from an arc tube 100 as a light source in a certain direction. The concave reflecting mirror 2 is formed in a cylindrical shape having one open end surface from which light is emitted, and an end portion facing the open end surface is formed into a hemispherical mirror surface portion 5 whose diameter gradually decreases. Has become. A mirror surface that reflects light is formed on the inner peripheral surface of the mirror surface portion 5. A through hole 5a is provided in the axial center portion of the end of the mirror surface portion 5, and a neck portion 4 is provided around the through hole 5a and protrudes outward concentrically with the through hole 5a. At the front end of the concave reflecting mirror 2 forming the light exit surface, a cover holding portion 6 having a diameter that increases over the entire circumference is provided.

A first front cover 21 made of a light-transmitting material such as hard glass is provided with a low-melting glass or an adhesive at the rear of the cover holding portion 6 formed at the front end of the concave reflecting mirror 2. Fixed. This first front cover 2
1 has an air inlet 21a having a diameter D1 at the center thereof. A second front cover 22 made of the same material as that of the first front cover 21 is fixed to the distal end of the cover holding section 6 with low melting point glass or an adhesive. An interval of a length L1 is provided between the first front cover 21 and the second front cover 22.

First front cover 2 in cover holding section 6
Between the first and second front covers 22, a plurality of air intakes 8 are provided at regular intervals in the circumferential direction. From the air inlet 8, air outside the concave reflecting mirror 2 flows into the cover holding portion 6 and flows into the concave reflecting mirror 2 through an air inlet 21 a provided in the first front cover 21. .

A plurality of air inlets 7 are provided at a front end of the concave reflecting mirror 2 close to the cover holding portion 6 at regular intervals in the circumferential direction. Air flows into the interior. The neck 4 is provided with a plurality of air outlets 9 at regular intervals in the circumferential direction, and air flows out of the concave reflecting mirror 2 from the air outlets 9.

FIG. 2 is a schematic diagram showing the configuration of the arc tube 100 attached to the concave reflecting mirror 2 described above.

An arc tube 100 comprising this high-pressure mercury lamp
As shown in FIG. 2, a bulb 101 is formed by a glass tube extending linearly. A light-emitting portion 10 bulging into a sphere is provided at the axial center of the bulb 101.
2 are provided. The inside of the light emitting unit 102 is hollow, and a gas such as mercury is sealed therein under high pressure. The front part of the light emitting unit 101 disposed along the axis of the concave reflecting mirror 2 with respect to the light emitting unit 102 is a front sealing part 103, and the opposite part is a rear sealing part. It is 104.

In the front sealing portion 103 and the rear sealing portion 104 of the valve 101, a front metal member 105 and a rear metal member 106 each formed in a thin plate shape are provided with the valve 10 respectively.
It is sealed along one axis. Each metal member 105
Discharge electrodes 107 and 108 are respectively joined to the ends of the discharge electrodes 107 and 106 which are close to each other. The discharge electrodes 107 and 108 are abutted at predetermined intervals in the light emitting unit 102. Front metal member 10
5, a first lead wire 109 projecting outward from the front sealing portion 103 to the front outside is joined to the front end of the rear metal member 106. A second lead wire 110 projecting rearward from the sealing portion 104 is joined.

A base 111 is attached to the rear end of the valve 102. The base 111 is fixed in the neck 4 formed at the rear part of the concave reflecting mirror 2, and the male base 112 is attached to the base 111 so as to project rearward. The second lead wire 110 projecting rearward of the bulb 101 is electrically connected to a male screw 112 attached to the base 111 via the base 111.
Then, the first lead wire 109 and the male screw portion 112 are connected to an external power supply circuit (not shown), and when a voltage is applied by the external power supply circuit, the discharge electrode 107 is formed.
And 108, a predetermined arc discharge occurs.

In the light source unit 1 having such a configuration, when the light emitted from the arc tube 100 is reflected by the inner surface of the concave reflecting mirror 2, the inside of the concave reflecting mirror 2 is heated. Then, the air in the concave reflecting mirror 2 is sucked in through the air outlet 9, or the air outside the concave reflecting mirror 2 is supplied to the air intakes 7 and 8,
Inside the concave reflecting mirror 2, an air flow shown by arrows A1 and A2 in FIG. 1 is generated.

The air flowing into the concave reflecting mirror 2 from the air inlet 7 at the front end of the concave reflecting mirror 2 is indicated by an arrow A in FIG.
As shown by 1, the air is discharged from the air outlet 9 to the outside along the inner peripheral surface of the concave reflecting mirror 2. Thereby, the concave reflecting mirror 2 is cooled, and the arc tube 100, particularly, the rear sealing portion 104 is cooled.

The air flowing into the cover holding portion 6 from the air inlet 8 provided in the cover holding portion 6, as indicated by an arrow A2 in FIG. Flows into the concave reflecting mirror 2 through the entrance 21a,
The air is discharged from the air outlet 9 to the outside. First front cover 2
The air that has flowed into the concave reflecting mirror 2 from the air inlet 21 a of the first
Since it flows along zero, the front sealing portion 103 is mainly cooled.

In the light source unit 1 of the first embodiment, the second front cover 22
Covers the front end side of the concave reflecting mirror 2, so that the arc tube 10
0 can be prevented from being scattered, and damage to peripheral members can be prevented.

Further, external air is introduced into the concave reflecting mirror 2 from the air inlet 8 formed on the side surface of the cover holding section 6 through an air inlet 21a formed at the center of the first front cover 21. The concave reflecting mirror 2
A flow of air for cooling the arc tube 100 or the like that has generated heat can be generated inside the device. In addition, the first front cover 2
1, the diameter D1 of the air inlet 21a is appropriately
The diameter D1 of the air inlet 21a can be changed.
By increasing the value, the required amount of cooling air can be obtained according to the heat generation state of the arc tube 10, and the inside of the concave reflecting mirror 2 can be efficiently cooled.

FIG. 3 is a sectional view showing another light source unit 1 of the first embodiment.

In the light source unit 1, a first front cover 21 having an air inlet 21a having a diameter D1 at the center is attached to the front end of the concave reflecting mirror 2. A cylindrical second cover holding portion 25 protruding forward is provided along the periphery of the air inlet 21 a formed in the first front cover 21. This second
A plurality of air inlets 8 are formed at regular intervals in the circumferential direction on the peripheral surface of the cover holding portion 25, and a second front cover 22 is provided at the front end thereof with the first front cover 21.
Are attached with an interval L1 between them. Other configurations are the same as those of the light source unit 1 shown in FIG.

In the light source unit 1, the second front cover 22 is provided with the air inlet 2 formed in the first front cover 21.
1a, the arc tube 1
Since it is possible to prevent the peripheral members from being damaged by the rupture of 00, the entire light source unit can be reduced in size.
The second front cover 22 may be formed to be slightly smaller than the air inlet 21 a formed in the first front cover 21.

(Embodiment 2) Hereinafter, a light source unit 1 according to Embodiment 2 of the present invention will be described with reference to the drawings.

FIG. 4 is a sectional view showing a schematic configuration of the light source unit 1 according to the second embodiment of the present invention.

The front sealing portion 103 of the arc tube 100 according to the second embodiment is different from the front sealing portion 10 of the arc tube 100 shown in FIG.
The first front cover 21 is partly protruded from the air inlet 21a of the first front cover 21 in a state where the first front cover 21 is fixed to the neck 4 of the concave reflecting mirror 2. Other configurations are the same as those of the light source unit 1 according to the first embodiment, and thus detailed description is omitted.

In the light source unit 1 according to the second embodiment, the air flowing from the air inlet 8 and flowing into the concave reflecting mirror 2 via the air inlet 21a formed in the first front cover 21 is reliably supplied. In this case, the cooling efficiency of the front sealing portion 103 can be improved.
00 and the concave reflecting mirror 2 can be efficiently cooled.

Embodiment 3 Hereinafter, a light source unit 1 according to Embodiment 3 of the present invention will be described with reference to the drawings.

FIG. 5 is a sectional view showing a schematic configuration of a light source unit 1 according to Embodiment 3 of the present invention.

In the light source unit 1 of the third embodiment, the conical guiding member 23 is provided on the second front cover 22 so as to face the air inlet 21 a formed in the first front cover 21.
Is provided. This guide member 23 is made of a transparent material,
For example, formed of hard glass, low melting glass,
Alternatively, it is fixed to the second front cover 22 by an adhesive.

The other configuration has the same configuration as that of the light source unit 1 of the first embodiment, and a detailed description thereof will be omitted.

In the light source unit 1 of the third embodiment, since the guide member 23 is provided to face the air inlet 21a formed in the first front cover 21, the air inlet 8 is provided.
From between the first front cover 21 and the second front cover 22 is bent by 90 degrees by the guide member 23 and smoothly flows into the concave reflecting mirror 2 along the shape of the guide member 23. . Therefore, the arc tube 100 and the concave reflecting mirror 2 can be efficiently cooled.

The guide member 23 may be formed in any other shape than the above-mentioned conical shape, as long as the shape allows air flowing in the cover holding portion 6 to be smoothly bent toward the concave reflecting mirror 2. Is also good.

[0046]

According to the light source unit of the present invention, a first front cover having an opening formed at a predetermined position on the light emission side of the concave reflecting mirror, and a predetermined interval in front of the first front cover are provided. An air inlet for taking in air from the outside is provided between the first front cover and the second front cover, the concave front mirror being provided at a predetermined position on the first front cover. Since the air inlet for allowing air to flow into the inside is provided, the second front cover can prevent the fragments from being scattered due to the rupture of the light emitting tube of the light source, and can also prevent the first front cover from the air inlet. The air can be introduced from the outside into the concave reflecting mirror through the air inlet provided in the mirror, and the inside of the concave reflecting mirror can be efficiently cooled.

Further, in the light source unit of the present invention, a part of the light source protrudes forward through the air inlet provided in the first front cover, so that the air provided in the first front cover is provided. The flow of the air flowing into the concave reflecting mirror through the inlet can be reliably applied to a part of the light source, and the cooling efficiency of the light source and the concave reflecting mirror can be further improved.

In the above light source unit of the present invention, the air flow is provided to the second front cover opposite to the air inlet provided to the first front cover, and the air flow is provided to the first front cover. By providing the guide member for guiding the inlet side, air can be smoothly introduced into the interior of the concave reflecting mirror from the air inlet provided in the first front cover, and the air flow path resistance can be reduced. it can. Therefore, the cooling efficiency of the light source and the concave reflecting mirror can be further improved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a light source unit according to Embodiment 1 of the present invention.

FIG. 2 is a schematic diagram illustrating a light source provided in the light source unit according to the first embodiment.

FIG. 3 is a sectional view showing another light source unit of the first embodiment.

FIG. 4 is a sectional view showing a light source unit according to Embodiment 2 of the present invention.

FIG. 5 is a sectional view showing a light source unit according to Embodiment 3 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source unit 2 Concave reflector 4 Neck 5 Mirror surface 6 Cover holder 7 Air inlet 8 Air inlet 9 Air outlet 21 First front cover 21a Air inlet 22 Second front cover 23 Induction member 100 Arc tube 101 Valve Reference Signs List 102 Light-emitting part 103 Front sealing part 104 Rear sealing part 105 Front metal member 106 Rear metal member 107 Discharge electrode 108 Discharge electrode 109 First lead wire 110 Second lead wire 111 Base 112 Male screw part

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuka Nakajin 22-22, Nagaikecho, Abeno-ku, Osaka-shi, Osaka F-term (reference) 3K014 AA01 LA01 LB03 3K042 AA01 AC02 AC06 CC03 CC04

Claims (5)

[Claims] A concave reflector having a light source, a front end face being open as a light emitting surface, a rear end facing the light emitting surface being a concave reflecting surface, and a light source being fixed to the rear end. A first front cover provided at a front end of the concave reflecting mirror so as to cover a light emitting surface of the concave reflecting mirror; and a concave surface provided at a predetermined interval in front of the first front cover. A second front cover provided at a front end of the reflector; and an air intake for taking in air from outside between the first front cover and the second front cover at the front end of the concave reflector. A light source unit provided with an air inlet for allowing air to flow into the concave reflecting mirror at a predetermined position of the first front cover. 2. The light source unit according to claim 1, wherein an air outlet for allowing air to flow out of the concave reflecting mirror is formed at a rear side of the concave reflecting mirror. 3. The light source unit according to claim 1, wherein an air intake for taking in air from outside is formed behind the first front cover at a front end of the concave reflecting mirror. 4. The light source unit according to claim 1, wherein a part of the light source protrudes forward through an air outlet formed in the first front cover. 5. A guide member is provided on the second front cover so as to face an air inlet formed in the first front cover and guide the air flow toward the air inlet. The light source unit according to claim 1.