JP2000338603A - Cooling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a projection type video display device which is good in cooling efficiency and has high image quality. SOLUTION: An electron cooling element 9 of semiconductor constitution is joined via a holder 10 to a reflection type video display element 4 and further, for the purpose of its heat radiation, a heat sink 11 is joined by means of screws, etc., thereto. Further, a cooling fan 12 is mounted thereto in a state separate from the heat sink 11 and a vent duct 13 is arranged in the evacuation direction of the cooling fan 12. The cooling in the central part of the heat sink 11 may be sufficiently executed by such constitution and the rotational vibration of the cooling fan 12 is not transmitted to the reflection type video display element 4. Video images of higher image quality may thus be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection type video apparatus for irradiating an image modulated into a video signal on a light valve with illumination light and enlarging and projecting the image on a screen by a projection lens. The present invention relates to a cooling device for efficiently cooling a light valve section.

[0002]

2. Description of the Related Art A projection type video apparatus basically comprises the following parts. That is, a light source lamp unit,
An optical unit and color unit that separates white light from a light source into red, blue, and green and modulates the light in accordance with image information. It is composed of a projection optical unit for enlarging and projecting the combined light.

In recent years, a projection type video apparatus uses a high-resolution display element to project image information more clearly, and furthermore, a brighter and higher brightness of a projection screen is promoted.

In addition, since the image display element of a high-brightness projection type image device absorbs heat from a light source in principle and limits the increase in luminance, as a countermeasure, the image display element is a transmission type image display element. Instead, a reflective image element using a liquid crystal or the like has been used. Here, even in the case of a reflection type image element, since slight light absorption occurs, forced cooling of the image element is necessary. As a configuration for this,
In general, an adjustment mechanism for accurately positioning the display element, a cooling element for forcibly cooling the display element, a heat sink for cooling the heat radiation side of the cooling element, and a cooling fan for air-cooling the heat sink are integrated.

Hereinafter, a conventional cooling device for a projection type video apparatus will be described with reference to the drawings.

FIG. 4 is a schematic diagram showing the overall configuration of a conventional projection type video apparatus. Generally, a light source lamp unit 1 which is a light source for optically enlarging and projecting image information, a filter 2 for removing light from the light source lamp unit 1 from infrared rays and ultraviolet rays and transmitting only visible light, An irradiation optical unit 3 for condensing light, and the condensed light is color-separated and guided to a reflection type image display element 4 (4a, 4b, 4c), and a reflection type image display element 4 (4a, 4b, 4c). )
And a color separation / combination prism unit 5 for color-combining light optically generated as image information, a reflection prism unit 6 for enlarging and projecting the combined image information, and a projection lens unit 7.

The light source lamp unit 1 generally includes a xenon lamp 101 and a concave mirror 102 for efficiently condensing light in a high-brightness image device. The color separation / combination prism unit 5 that separates and combines the light from the light source lamp unit 1 into red, green, and blue is, for example, a blue reflection dichroic mirror 501 and a red reflection dichroic mirror 50.
2 and a dichroic mirror 503 that transmits green light, and is color-separated into R, G, and B from each film characteristic.
G, B, and the reflection type video display elements 4a, 4b. The light modulated into image information in 4c is combined again by the color separation / combination prism unit 5. The reflecting prism 6 is an integral prism having a so-called half mirror configuration, which transmits the light from the irradiation optical unit 3 and guides the color-combined light to the projection lens unit 7.

FIG. 5 is a diagram showing a cooling structure of a conventional general reflection type image display device 4. As shown in FIG. Reflective image display device 4
(4a, 4b, 4c) is bonded with an adhesive or the like to a position adjustment mechanism 8 capable of adjusting the planar position and focus of each of R, G, and B, and the position adjustment mechanism 8 is bonded to the color separation / combination prism unit 5. It is accurately positioned and fixed with an agent.
An electronic cooling element 9 made of a semiconductor is joined to the reflection type image display element 4 via a holder 10, and a heat sink 11 for radiating the heat is attached to the electronic cooling element 9.
And a cooling fan 12 for cooling the heat sink 11 is assembled integrally with the holder 10 with screws or the like (not shown).

A conventional cooling apparatus for a projection type video apparatus using a reflection type video element is disclosed in, for example, Japanese Patent Application Laid-Open No. 10-31.
There is one described in Japanese Patent Publication No. 9853. According to the invention described in the publication, the heat generated in the video display element is radiated, the temperature rise of the video display element is suppressed, and the video display element can be positioned and held at a desired position with high precision. A holder is disclosed.

[0010] Further, as another cooling structure of the image element,
Japanese Patent Application Laid-Open No. Hei 10-319379 discloses a cooling configuration of a transmission type video device of a liquid crystal display device, which uses a heat pipe.

[0011]

However, in such a configuration, in the case of achieving higher luminance, more light is concentrated on the reflective image display element 4, so that it is necessary to improve the cooling performance. For this purpose, a larger electronic cooling element 9, a heat sink 11, and a cooling fan 12 are required. Such an increase in the size of the device causes an increase in the weight of each part, and further causes a mechanical shift of the position adjusting mechanism 8 due to the vibration of the device, and the vibration of the cooling fan 12 affects the reflective display element 4. May cause image quality degradation.

Also, as indicated by the arrow in FIG.
In the state of ventilation from the cooling fan 12, the central portion of the heat sink 11 is a motor driving portion of the cooling fan 12, so that only the outer peripheral portion of the heat sink 11 is cooled, and the cooling is not performed as a whole. Efficiency is worsening.

Further, in the configuration described in Japanese Patent Application Laid-Open No. 10-319853, a sufficient heat radiation effect can be obtained in a low-luminance video device, but in a video device aiming for high luminance, a display element other than the above configuration is forcibly applied. A cooling element for cooling, a heat sink for cooling the heat radiation side of the cooling element, and a cooling fan for air cooling the heat sink are required, and these are generally configured integrally.

Further, in the configuration described in Japanese Patent Application Laid-Open No. Hei 10-319379, the heat pipe is generally made of metal, and there is a problem that adjustment by an adjusting mechanism is difficult due to an increase in weight and metal rigidity.

The present invention pays attention to such a point, and realizes high brightness,
An object of the present invention is to provide a cooling device for a video display element that supports high resolution.

[0016]

SUMMARY OF THE INVENTION In order to solve the above-mentioned conventional problems, a cooling device in a projection display device according to the present invention is characterized in that the cooling of an image display element is performed by a cooling element, a heat sink and a cooling fan. Is the same as
The heat sink can be installed without increasing the weight of the image display element by adding a duct configuration to regulate the wind direction to the exhaust port of the cooling fan based on separating the installation of the cooling fan from the image display element. Another object of the present invention is to provide an efficient cooling configuration.

According to this configuration, it is possible to increase the cooling capacity of the image display element, and it is possible to realize a high-brightness and high-resolution image display device.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) In the overall configuration of the projection type video apparatus described with reference to FIG. 4, the gist of the present invention is a cooling device for three reflection type video display elements 4 provided for R, B and G, respectively. This will be described in detail below with reference to the drawings. Since the configuration is common to the three, one reflective video display element 4 will be described.

FIG. 1 is a view showing a cooling structure of the reflection-type image display device 4. The reflection-type image display device 4 is provided with a position adjustment mechanism 8 capable of adjusting the plane position of each of R, G, and B and adjusting the focus. The position adjusting mechanism 8 is accurately positioned and fixed to the color separation / combination prism unit 5 with an adhesive or the like. An electronic cooling element 9 made of a semiconductor is joined to the reflection type image display element 4 via a holder 10, and the electronic cooling element 9 has a heat sink 11 for radiating heat of the electronic cooling element 9. None). The heat sink 11 is made of a material having a high thermal conductivity, such as aluminum, and has a fin shape on the surface.

Reference numeral 12 denotes a cooling fan which is attached separately from the heat sink 11, and further has a cylindrical ventilation duct 13 provided in the exhaust direction. As described above, the cooling fan 12 is arranged at a position away from the heat sink 11 and the cooling fan 12 is
Since the ventilation path up to 1 is covered by the duct 13, the ventilation from the cooling fan 12 can sufficiently flow to the center of the heat sink 11 as shown by the arrow, and the heat sink 11 can be efficiently cooled.

Further, since the cooling fan 12 is not directly fixed to the reflection type image element 4, the rotational vibration of the cooling fan 12 is not transmitted to the reflection type image element 4, and a higher quality image can be obtained. .

Although not shown, the cooling fan 12
May be not only an axial fan as shown in FIG. 1, but also a so-called sirocco fan which is more advantageous in air volume and pressure. (Embodiment 2) FIG. 2 shows another embodiment of the present invention.

The reflective image display element 4 is joined to the position adjusting mechanism 8 in the same manner as in the first embodiment, and the thermoelectric cooler 9 is joined via the holder 10 as in the first embodiment. Further, a heat sink 11 for dissipating the heat is joined to the electronic cooling element 9 with screws (not shown) or the like.

As in the first embodiment, the cooling fan 12 is attached separately from the heat sink 11, and a cylindrical ventilation duct 13 is provided in the exhaust direction.

In this embodiment, the second heat sink 14, the electronic cooling element 15, the third heat sink 16, and the external cooling fan 17 are provided between the cooling fan 12 and the exhaust port from the ventilation duct 13. Have been.

In this configuration, since the second heat sink 14 cooled by the electronic cooling element 15 is in the ventilation duct 13, the air from the cooling fan 12 flowing in the ventilation duct 13 is cooled by the second heat sink, and Is cooled by air below the normal environmental temperature, so that the cooling efficiency is further improved. The heat of the electronic cooling element 15 is electrically heated by the third heat sink 16 and further cooled by the external fan 1.
Cooled at 7. The cooling external fan 17 is not affected by the cooling air from the third heat sink 16 if the cooling external fan 17 is installed at a position distant from the reflective image element 4, for example, outside the image apparatus.

Further, the units from the second heat sink 14 to the external cooling fan 17 are not limited to the configuration shown in FIG. 2, and the cooling efficiency can be further improved if they are configured to cover the outer periphery of the ventilation duct 13. At this time, a plurality of cooling external fans 17 may be radially provided on the outer peripheral portion of the ventilation duct 13, and the cooling external fan 17 may be provided from one cooling external fan 17.
Air may be sent for cooling to the third heat sink 16 provided on the outer periphery of the ventilation duct 13 through a duct further provided on the outer periphery of the ventilation duct 13.

Further, as shown in FIG. 3, air can be sent to the ventilation duct 13 and the third heat sink 16 in FIG. 2 by one large cooling fan.

Further, in FIG. 2, the heat sink 11, the second heat sink 14, and the third heat sink 16 are arranged in a direction where the ventilation resistance is low as a matter of course. (Embodiment 3) FIG. 3 shows a cooling configuration in which the above-mentioned ventilation duct system is constituted by at least one cooling fan 12 and the three reflection type image elements 4 (4a, 4b, 4c) are simultaneously air-cooled. Show. The ventilation duct 13 is divided into three at the exhaust port of the cooling fan 12, and each is divided into branch ducts 18 (18a, 1a).
8b, 18c). In this configuration, not only efficient cooling by the ventilation duct 18 but also a compact image display device can be realized because of at least one cooling fan 12. Note that the branch duct 18 may be made of not only metal but also rubber or plastic. Further, a second heat sink 14 for cooling the inside of the duct, an electronic cooling element 15, a third heat sink 16, and an external fan 17 for cooling may be provided in the ventilation duct 13 shown in FIG.

Here, as for the number of cooling fans, it is conceivable that cooling fans are provided in accordance with the cooling locations. However, as in the present embodiment, by arranging the air blowing paths, several cooling locations can be provided. By using one large cooling fan, the space can be effectively used, and beats generated when a plurality of cooling fans are used can be suppressed.

That is, when a plurality of fans are used, since the rotation speed of each fan is different, a beat of rotational vibration is generated, and the vibration amount is much larger than when one fan is used. This problem can be avoided by the present embodiment.

[0032]

As described above, according to the present invention, in a projection type image apparatus, a cooling fan for cooling a reflection type image element is mechanically separated from a reflection type image element, so that a reflection type image element is provided. Cooling air can be sent evenly to the image element, and the reflective image element can be cooled efficiently. At the same time, the rotational vibration of the cooling fan is not transmitted to the reflective image element. A high quality video image can be obtained.

Further, according to the present invention, a cooling structure is further provided in the middle of the air supply path from the cooling fan to the reflection type image element. With such a structure, the cooling efficiency can be further improved.

According to the present invention, in a cooling device for a projection type image apparatus, a plurality of ventilation ducts are provided for a plurality of reflection type image elements to be cooled, and a single cooling fan is used to remove the plurality of ventilation ducts from the plurality of ventilation ducts. By blowing air, the number of cooling fans is reduced and the size of the device can be reduced.
It is possible to prevent the beat of rotational vibration generated when a plurality of cooling fans are used.

[Brief description of the drawings]

FIG. 1 is a cooling configuration diagram of a reflection type image element according to a first embodiment of the present invention.

FIG. 2 is a cooling configuration diagram of a reflection type image element according to a second embodiment of the present invention.

FIG. 3 is a diagram illustrating a cooling configuration of a reflection type image element according to a third embodiment of the present invention.

FIG. 4 is a schematic diagram showing a configuration of a conventional projection type video apparatus.

FIG. 5 is a schematic view showing a cooling structure of a conventional reflection type image element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source lamp unit 2 Filter 3 Irradiation optical unit 4 Reflection type image element 5 Color separation / combination prism unit 6 Reflection prism unit 7 Projection lens unit 8 Position adjustment mechanism 9 Electronic cooling element 10 Holder 11 Heat sink 12 Cooling fan 13 Ventilation duct 14 Second Heat sink 15 Electronic cooling element 16 Third heat sink 17 External cooling fan 18 Branch duct

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Toshiyuki Ueda 1006 Kazuma Kadoma, Kazuma, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd. 5C058 BA35 EA02 EA12 EA13 EA14 EA21 5C060 EA01 GA01 JB00 5F036 AA01 BA33 BB05 BB05

Claims (5)

[Claims] A light source lamp unit, an irradiation optical unit for condensing light from the light source lamp unit, a reflection type image element for optically generating image information from the condensed light,
A color combining prism unit for combining colors of optical information of a reflective image element, a projection lens unit for enlarging and projecting image information, an electronic cooling element for cooling the reflective image element, and a heat sink for cooling the electronic cooling element And a cooling fan for cooling the heat sink, wherein the cooling fan is mechanically separated from the reflective image element. 2. A light source lamp unit, an irradiating optical unit for condensing light from the light source lamp unit, and a reflection type image element for optically generating image information from the condensed light;
A color combining prism unit for combining colors of optical information of a reflective image element, a projection lens unit for enlarging and projecting image information, an electronic cooling element for cooling the reflective image element, and a heat sink for cooling the electronic cooling element And a cooling fan for cooling the heat sink, wherein the cooling fan is mechanically separated from the reflective image element, and a cylindrical ventilation duct is provided at an exhaust port of the cooling fan. Cooling device for video equipment. 3. A light source lamp unit, an irradiation optical unit for condensing light from the light source lamp unit, and a reflection type image element for optically generating image information from the condensed light;
A color combining prism unit for combining colors of optical information of a reflective image element, a projection lens unit for enlarging and projecting image information, an electronic cooling element for cooling the reflective image element, and a heat sink for cooling the electronic cooling element And a cooling fan for cooling the heat sink, the cooling fan is mechanically separated from the reflection type image element, and a cylindrical ventilation duct is provided at an exhaust port of the cooling fan. A cooling device for a projection type video device, wherein a heat sink for cooling air in the duct, an electronic cooling device, and a cooling fan are configured in the duct. 4. A light source lamp unit, an irradiation optical unit for condensing light from the light source lamp unit, a reflection type image element for optically generating image information of the condensed light,
A color combining prism unit for combining colors of optical information of a reflective image element, a projection lens unit for enlarging and projecting image information, an electronic cooling element for cooling the reflective image element, and a heat sink for cooling the electronic cooling element And a cooling fan for cooling the heat sink, wherein the cooling fan is mechanically separated from the reflection-type image element, and at least one cooling fan has at least two branched air outlets. A cooling device for a projection type video device characterized by comprising a branch ventilation duct of (1). 5. The cooling fan according to claim 4, wherein the cylindrical branch ventilation duct provided at the exhaust port of the cooling fan has at least two air passages in the direction of the rotation surface of the cooling fan near the exhaust port of the cooling fan corresponding to the branch flow rate. A cooling device for a projection-type image device, wherein the device is branched into a plurality of partitions, a branch duct is formed in a state of being branched, and the reflection-type image element is cooled.