JP2001330818A - Electronic device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high efficiency cooling structure of a polarizing plate and a liquid crystal panel. SOLUTION: Tapes formed by using a high heat conductive material are stuck to the polarizing plate and the liquid crystal panel and a sheet or grease formed by using a high heat conductive material is applied on the connecting part of a chassis and the polarizing plate or the liquid crystal panel to thermally connect the chassis and the polarizing plate or the liquid crystal panel. Thus the heat radiation of the polarizing plate and the liquid crystal panel can be realized without increasing a flow path sectional area formed by a guide which controls the size of a fan and the flow of air blew from the fan.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling structure of an electronic device in which a deflecting plate and a liquid crystal panel constituting an optical system are accommodated in a housing, wherein the deflecting plate and the liquid crystal panel are maintained at a predetermined temperature. It relates to a cooling device.

[0002]

2. Description of the Related Art The prior art is disclosed in Japanese Patent Application Laid-Open No. 9-130713.
As disclosed in Japanese Patent Application Laid-Open Publication No. H10-209, a duct for controlling a flow from a fan is provided inside a chassis to send cooling air to a deflection plate and a liquid crystal panel.

[0003]

In an electronic device having an optical system such as a liquid crystal type projector, light is transmitted through a deflecting plate or a liquid crystal panel to generate heat, so that the internal temperature distribution becomes non-uniform. Color unevenness occurs when you do. For this reason, air is sent by a fan to cool the deflecting plate and the liquid crystal panel. However, in the conventional method, the number of fans to be put in the housing or the flow rate is devised to increase the amount of air hitting the heating element. However, there is a demand for miniaturization and quietness of the housing size, and there is a limit to the number of fans to be accommodated in the housing and a device for the flow path, and there is a problem that the miniaturization of the housing size becomes difficult. . Further, the cooling air tends to concentrate on the central part of the deflection plate and the liquid crystal panel, and the cooling on the outer peripheral part has not been considered.

It is an object of the present invention to efficiently conduct deflection and liquid crystal panels by using conduction cooling and forced cooling using a fan against heat generated by the deflection plates and liquid crystal panels accompanying irradiation of an electronic device having an optical system. An object of the present invention is to provide an electronic device that can be uniformly cooled and has a structure suitable for a small housing.

[0005]

SUMMARY OF THE INVENTION In a chassis for forming an optical path, which accommodates a deflecting plate and a liquid crystal panel constituting an optical system, a high heat conduction is provided to an end portion for holding the deflecting plate or the liquid crystal panel on the chassis. A sheet or grease having a liquid compound is applied, and the deflection plate or the liquid crystal panel is thermally connected to a wall constituting an optical path. Further, a guide is provided in the chassis, and cooling air from the fan is directly blown to the deflection plate, the liquid crystal panel, and the chassis. In addition, a tape of copper or aluminum having high thermal conductivity is attached to a portion where light is not transmitted between the deflection plate and the liquid crystal panel. In addition, all or some members of the chassis are made of magnesium or aluminum to enhance the heat radiation effect from the chassis.

That is, the heat generated by the deflecting plate and the liquid crystal panel in the chassis which forms the optical path of the electronic device having the optical system is transmitted to the connecting portion between the deflecting plate and the end of the liquid crystal panel and the chassis, resulting in high heat. Conducted to the chassis by a sheet or grease having a conductive compound. By using a sheet or grease having a compound having high thermal conductivity, the contact thermal resistance between the end portion of the deflecting plate and the liquid crystal panel and the holding portion with the chassis is reduced. Heat conduction to the connection is promoted.

[0007] The heat conducted to the chassis is spread over a large area of the chassis surface. Part of the heat generated in the deflection plate or the liquid crystal panel is transmitted to the chassis by heat conduction, so that the temperature of the deflection plate or the liquid crystal panel decreases. Air flowing through the chassis by the fan installed in the chassis flows through the flow path defined by the flow control guide provided inside the chassis. And the chassis itself, which has been thermally conducted from the end portions of the deflection plate and the liquid crystal panel, can be cooled. With the above operation, heat can be efficiently radiated between the deflection plate and the liquid crystal panel without increasing the size of the fan and the cross-sectional area of the flow path in the chassis.

[0008]

1 to 3 show an embodiment of the present invention. FIG. 1 is a top view of a chassis portion forming an optical path of the electronic device of the present embodiment. The electronic device includes a chassis 11 forming an optical path, deflecting plates (incident-side deflecting plates 1, 7, 9 and emitting-side deflecting plates 3, 5, 8), liquid crystal panels 2, 6, 10 and a prism 4 forming an optical system. And a lamp 17. The incident light emitted from the lamp 17 and entering the chassis 11 is divided into three paths, each of which is transmitted in the order of the incident side deflection plate, the liquid crystal panel, and the emission side deflection plate and projected through the prism 4. . Part of the heat generated in the deflection plate and the liquid crystal panel is transmitted to the contact portion 12 between the chassis and the end portion of the deflection plate or the liquid crystal panel, and is transmitted through a sheet or grease having a highly thermally conductive compound applied to the contact portion. Then, the heat is transmitted to the chassis 11, diffused into a large area of the chassis 11, and radiated to the surroundings.

Further, three guides 13, 14, and 15 for controlling the flow of air from the fan are provided in the chassis.
Is provided. By providing the guide, the air discharged from the fan can be directly used for cooling the deflection plate and the liquid crystal panel. Further, the air discharged from the fan installed in the chassis also cools the chassis body to which heat is transmitted by heat conduction from the deflection plate and the liquid crystal panel. That is, a part of the heat generated in the deflectors 1, 7, 9, 3, 5, 8 is transmitted to a contact portion between the deflector and the chassis, and is transmitted to the chassis by a sheet or grease having high thermal conductivity. It is also cooled by a fan. The deflection plate is also cooled by the air passing through the guide. The same structure applies to the deflection plate and the liquid crystal panel that form three paths.

FIG. 2 is an enlarged view of a connection portion between the end of the deflection plate 1 and the contact portion 12 on the chassis side in the electronic device of the present embodiment. A sheet or grease 16 having a compound having high thermal conductivity is applied between the end of the deflection plate 1 and the contact portion 12, and is held on the chassis 11.

A part of the heat generated in the deflection plate 1 is transferred to the contact portion 12 on the chassis side at the end of the deflection plate 1 through a sheet or grease 16 having a compound having high thermal conductivity. The heat transmitted to the contact portion 12 on the chassis side is diffused over a large area of the chassis 11 and is radiated to the surroundings. The same applies to the liquid crystal panel.

In the embodiment shown in FIG. 3, a portion of the deflecting plate and the liquid crystal panel through which light does not pass (the deflecting plate and the outer peripheral portion of the liquid crystal panel).
In this structure, a tape 18 of copper or aluminum having good heat conductivity is attached. Part of the heat generated by the deflection plate and the liquid crystal panel is further transmitted in the plane direction by the tape 18, and at the end of the deflection plate and the liquid crystal panel, as shown in FIG. It is conducted to the chassis side 12 through the grease 16 and the chassis 11
Is diffused and dissipated in a large area.

The deflection plate and the liquid crystal panel generally have a lower thermal conductivity than metal. Therefore, by attaching a metal tape to the surfaces of the deflection plate and the liquid crystal panel, the heat conductivity in the plane direction is promoted, and the cooling efficiency by heat conduction to the chassis 11 forming the optical path is increased.

In another embodiment, magnesium or aluminum may be used as the material of the chassis member in order to enhance the heat radiation effect of the chassis. Thereby, heat conduction in the chassis 11 is promoted, and heat can be diffused to a wider area.

As another embodiment, a structure in which the above-described embodiments are combined may be employed.

With the above effects, cooling can be performed with a smaller amount of air flow, so that power consumption of the fan can be reduced, noise can be reduced, and the size of the housing can be reduced.

[0017]

According to the present invention, the deflection plate and the liquid crystal panel can be uniformly cooled by using the fan, and can be efficiently cooled by a structure suitable for a small housing.

[Brief description of the drawings]

FIG. 1 is a top view of an electronic device according to a first embodiment of the present invention.

FIG. 2 is an enlarged view around a deflection plate in FIG.

FIG. 3 is an enlarged view around a deflection plate according to a second embodiment of the present invention.

[Explanation of symbols]

1,3,5,7,8,9 ... deflecting plate, 2,6,10 ... liquid crystal panel, 4 ... prism, 11 ... chassis, 13,14,
15: guide, 16: flexible heat conductive member, 17: lamp,
18 ... thermal conductive tape.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/74 H04N 5/74 E (72) Inventor Yoshihiro Kondo 502 Kandamachi, Tsuchiura-shi, Ibaraki Pref. 2H088 EA14 HA18 HA28 MA20 2H089 HA40 JA10 QA06 TA15 UA05 5C058 AA06 AB06 BA35 EA02 EA26 EA52 5G435 AA12 BB17 CC12 DD02 DD05 EE02 FF05 GG03 GG44 LL15

Claims (1)

[Claims] A lamp, a deflecting plate, a liquid crystal panel, a fan, a chassis forming an optical path, and the like constituting an optical system are housed in a housing, and light emitted from the lamp passes through the deflecting plate and the liquid crystal panel. In an electronic device projected onto an external screen, a deflecting plate, a liquid crystal panel, and the like are cooled by a fan installed in a chassis, and a deflecting plate, a liquid crystal panel, Are thermally connected to the chassis.