JPH0720658Y2 - Liquid crystal display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a liquid crystal television and a liquid crystal projector that illuminate a back light from a rear surface of a transmissive liquid crystal display and display an image by the light transmitted through a liquid crystal layer. The present invention relates to a liquid crystal display device such as a device.

[Prior Art and its Problems] Conventionally, in a liquid crystal display device using a transmissive liquid crystal display such as a liquid crystal projector device, an image is displayed by transmitting light by a backlight. However, when a backlight with high brightness and high light quantity is used to improve the contrast of an image, the liquid crystal material of the liquid crystal display body is heated by the heat generated by the light source for the backlight and the infrared rays contained in the light from the park, Due to the temperature rise, the liquid crystal material is deteriorated, and uneven brightness or contrast unevenness is apt to occur in the image, which causes a problem that a high quality image cannot be obtained.

[Object of the Invention] The present invention has been made in view of the above-mentioned circumstances, and its object is to improve the heat generated by the light source for the backlight and the infrared rays contained in the light from the light source. An object of the present invention is to provide a liquid crystal display device which can obtain a high-quality image stably and which is simple and does not increase in size.

[Summary of the Invention] A liquid crystal display device of the present invention has a liquid crystal display panel for achieving the above-mentioned object, a liquid-filled cooling unit provided facing the light incident side of the liquid crystal display panel, The liquid is isolated from the outside of the cooling part, and a part of the liquid projects into the cooling part so as not to interfere with the display area of the liquid crystal display panel and comes into contact with the liquid. Formed in the shape of a fin protruding to the outside of the part,
And a heat dissipation unit for dissipating the heat of the liquid to the outside of the cooling unit.

[Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings.
In FIG. 1 and FIG. 2, the liquid crystal display 1 is composed of a front upper glass substrate 2 and a rear lower glass substrate 3. In this case, although not shown in the drawing, for example, a liquid crystal layer 1a is provided between the upper glass substrate 2 and the lower glass substrate 3 as shown in FIG. It is sealed with stopper 1b. Similarly, although not shown in the drawing, a polarizing plate having a size covering the screen size 4 is provided on each outer surface of the upper glass substrate 2 and the lower glass substrate 3.

On the other hand, a cooling unit 6 is attached to the back surface of the lower glass substrate 3 which constitutes the liquid crystal display 1 via a sealing adhesive 5. The cooling unit 6 includes a transparent panel (for example, a transparent glass plate) 7 that is attached to the lower glass substrate 3 at a constant interval, and a cooling layer 8 formed by the transparent panel 7 and the lower glass substrate 3. The cooling layer 8 is composed of a transparent cooling liquid (for example, water + ethylene glycol) 8a and a mesh member 9, and a fin portion 10 for radiating heat that supports an end portion of the mesh member 9.

In the above, the mesh member 9 is formed in a lattice shape corresponding to the gaps between the image dots of the liquid crystal display 1, and is made of a metal material having good thermal conductivity (eg, silver, copper, aluminum, etc.). Has been. The mesh member 9 is formed in a lattice shape using a wire having a thickness that apparently closes the gaps between the dots, and also serves as a black stripe for the image of the liquid crystal layer 1a. The mesh member 9 may be a non-metal as long as it has a good thermal conductivity.

Further, as shown in the enlarged view of FIG. 3, the heat dissipation fin portion 10 includes a fin 10a and a rib 10 for mutually supporting the fin 10a.
b, a frame 10c that integrally supports the fin 10a, an inner wall (T type) that is located inside the frame 10c and that supports each end of the mesh member 9 and that guides convection of the cooling liquid 8a described later. 10d and the adhesive surfaces 10e, 10e on the front and rear surfaces of the frame 10c are formed.

Further, in the cooling part 6, a bulging auxiliary cooling layer 8b is formed integrally with the cooling layer 8 at the upper and lower center where the convex portion of the fin part 10 is formed, and is positioned above the cooling layer 8. In this auxiliary cooling layer 8b, the bubbles are gathered when the cooling liquid 8a is heated to generate convection. A fin for speeding up the endothermic cooling of the cooling liquid 8a of the auxiliary cooling layer 8b
There is a little more 10f inside. The reason why the auxiliary cooling layer 8b is in the upper and lower positions is that the upper and lower sides of the liquid crystal display device can be freely selected, and the lower auxiliary cooling layer 8b serves as a precipitation space for impurities.

FIG. 4 shows a natural convection state of the cooling liquid 8a in the cooling layer 8. In the use of this liquid crystal display device, when the light 11 from the light source for the backlight is applied to the back surface of the liquid crystal display 1 as shown in FIG. 2, the heat from the light source or infrared rays contained in the light 11 causes In the liquid crystal display 1, the central portion A of the image size 4 is heated. Then, due to this heating, natural convection occurs in the cooling liquid 8a, and the cooling liquid in the central portion A is
8a rises to reach upper region B.

In the upper region B, since the auxiliary cooling layer 8b having the fins 10f is formed as described above, the cooling liquid 8a rising here is formed.
Is efficiently cooled by the auxiliary cooling layer 8b. And
The cooled cooling liquid 8a in the upper region B is guided to the left and right regions by the inner surface of the inner wall 10d which is provided so as not to return directly to the center of the cooling layer 8, and is cooled along the inner surface of the inner wall 10d. While moving, it moves to the left and right side portions C and further reaches the lower central portion D of the lower center. The cooling liquid 8a in the lower region D again flows into the central portion A by natural convection. Since the temperature of the cooling liquid 8c in the space other than the central portion A is lower than that in the vicinity of the central portion A, natural convection is performed only in the cooling layer 8.
In the process of the convection, when it descends along the outer surface of the inner wall 10d, heat is taken by the fin portion 10 side to be cooled. Further, the cooling layer 8 is formed thin so that the flow velocity of natural convection can be quickly obtained, and efficient cooling can be obtained. Further, the cooling by the convection is accelerated by the mesh member 9. Since the mesh member 9 has a function of blocking the image dots of the liquid crystal display 1 from the backlight, it is possible to improve the contrast of the image of the liquid crystal display 1 in addition to the above heat dissipation.

FIG. 5 shows another embodiment in which the shape of the fin 10a is changed.
In the fin 10a of this embodiment, a part of the fin 10a is cut as shown by an inclined portion 12 with respect to the rectangular fin 10a shown in the above embodiment. By forming the shape of the fins 10a as shown in this embodiment, the convection of the atmosphere between the fins 10a can be accelerated and the heat dissipation effect of the fins 10a can be improved.

Although the cooling unit 6 integrally attached to the liquid crystal display body 1 is provided on the back surface of the liquid crystal display body 1 in the above embodiment, the cooling unit 6 is provided on the front surface of the liquid crystal display body 1. Good.

Further, although the cooling medium filled in the cooling layer 8 is a liquid in the above embodiment, it may be an appropriate gas as long as a cooling effect or a heat dissipation effect can be obtained.

[Advantages of the Invention] As described above, the liquid crystal display device of the present invention is provided with the cooling unit that faces the light incident side of the liquid crystal display panel and in which the liquid is sealed, and the cooling unit is provided with the liquid and the outside of the cooling unit. While being isolated from each other, a part thereof protrudes into the cooling part and contacts the liquid to the extent that it does not interfere with the display area of the liquid crystal display panel, and another part protrudes outside the cooling part to form a fin shape. The liquid of the cooling unit absorbs the heat of the liquid crystal display panel, and the heat of the backlight light source or the light from the light source is provided because the heat dissipation unit for radiating the heat of the liquid to the outside of the cooling unit is provided. Even when overheated by infrared rays contained in, high-quality images can be stably obtained without uneven brightness and uneven contrast, and the heat absorbed by the liquid does not partially interfere with the display area of the liquid crystal display panel. In the cooling section The effect that the liquid crystal display device itself can be simplified and does not become large because it projects to the liquid and comes into contact with the liquid, and the other part projects to the outside of the cooling part and is directly emitted by the fin-shaped efficient heat dissipation part. Is obtained.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, FIG. 1 is a front view of a liquid crystal display device shown by removing the right half of the liquid crystal display body, FIG. 2 is a sectional view taken along line II-II shown in FIG. Figure 3 shows I shown in Figure 1.
FIG. 4 is an enlarged perspective view of the II portion, FIG. 4 is an explanatory view showing a natural convection state in the cooling layer, and FIG. 5 is a side view showing another embodiment of the fin shape. 1 ... Liquid crystal display, 6 ... Cooling part, 8 ... Cooling layer, 9 ...
… Mesh member, 10 …… Fine part.

Claims (1)

[Scope of utility model registration request] 1. A liquid crystal display panel, a cooling section, which is provided facing the light incident side of the liquid crystal display panel, and in which a liquid is sealed, and the liquid and the outside of the cooling section are isolated from each other. A part of the liquid formed in a fin shape so as to project into the cooling part and come into contact with the liquid to the extent that a part does not interfere with the display area of the liquid crystal display panel, and another part projects outside the cooling part. A liquid crystal display device, comprising: a heat dissipation part for dissipating heat to the outside of the cooling part.