JPH0754379B2 - Liquid crystal display - Google Patents

Description

Description: TECHNICAL FIELD [0001] The present invention is directed to illuminating a plurality of transmissive liquid crystal display panels with backlight light from the rear surface, and transmitting light through the liquid crystal layer of the liquid crystal display panel to produce a color image. The present invention relates to a liquid crystal display device such as a liquid crystal television or a liquid crystal projector device that performs display.

[Prior Art and its Problems] Conventionally, in a liquid crystal display device that displays a color image by transmitting light of a backlight through a plurality of transmissive liquid crystal display panels, no radiation countermeasures have been taken for the liquid crystal display panels. . Therefore, when a light source of high brightness and high light quantity is used as the light source for the backlight to improve the contrast of the image, the liquid crystal material of the liquid crystal display panel may be generated due to heat generation of the light source or infrared rays contained in the light from the light source. It is easily heated and deteriorated, and uneven brightness, color shift, and
There is a problem in that a high quality image cannot be obtained due to uneven contrast.

[Object of the Invention] The present invention has been made in view of the above circumstances, and an object of the present invention is to efficiently cool a liquid crystal display panel while convecting a refrigerant in a cooler. Another object of the present invention is to provide a liquid crystal display device including a cooler capable of cooling a liquid crystal display panel.

In order to achieve the above-mentioned object, the present invention provides a cooler for cooling a liquid crystal display panel of a liquid crystal display device in close contact with one surface side of the liquid crystal display panel, and stores a refrigerant in the cooler. A cooling layer is provided, and a passage for circulating the refrigerant inside the cooler is provided outside the display area of the liquid crystal display panel around the cooling layer, while efficiently convecting the refrigerant in the cooler. The liquid crystal display panel is cooled so that the liquid crystal display panel can be cooled well.

Embodiments of the Invention Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of a color liquid crystal projector device 3 which is a sectional view of the liquid crystal display device 1 of the present invention set in an image display section 2, and FIG. 2 is a side view of the same.

In this color liquid crystal projector device 3, three optical system projection devices 4R, 4G, and 4B that form a color image are arranged adjacent to each other, and the projection device 4R projects a red image.
The projection device 4G projects a green image and the projection device 4B projects a blue image. Then, the images projected in the respective colors from the angle projection devices 4R, 4G, and 4B are formed on the screen 5 surface so that a color image is projected.

In the above, the projection images from the projection devices 4R, 4G, 4B are
Colors for the three primary colors are added by the cooling unit (see FIG. 4) 8 of the liquid crystal display device 1 provided for each of the projection devices 4R, 4G, and 4B. In the figure, reference numeral 6 is a light source lamp for a backlight.

FIG. 3 is an enlarged front view of the liquid crystal display device 1 which is set in the image display section 2 of the liquid crystal projector device 3. In this figure, the right half of the liquid crystal display panel 7 on the front is deleted and the liquid crystal display panel 7 is removed. 7 shows the internal structure of the cooling unit 8 that is integrally arranged on the back surface of the.

FIG. 4 is a sectional view taken along the line AA shown in FIG.

As shown in FIG. 4, the liquid crystal display panel 7 is formed by laminating transparent glass substrates 7a and 7b. Although not shown in the figure, a liquid crystal material is enclosed between the two glass substrates. ing. Then, electrodes forming pixels are provided in a matrix on the inner surfaces of the glass substrates 7a and 7b in which the liquid crystal material is sealed. In addition, this liquid crystal display panel 7
Although not shown in the drawing, polarizing plates are attached to the both outer surface positions outside of the display device so as to cover the screen size 9.

Further, as shown in FIGS. 3 and 4, the cooling unit 8 has a transparent panel 8a having a size facing the glass substrate 7b of the liquid crystal display panel 7, and the transparent panel 8a and the glass substrate 7b are fixed. The cooling layer 10 formed at intervals and the cooling layer 10
The heat dissipation fins 11a and the heat absorption fins 11b and 11c are provided in the fins 11.

The fin portion 11 has a frame shape having a size matching the edges of the glass substrate 7b and the transparent panel 8a, and in the case of this embodiment, the heat dissipation fin 11a is provided at the upper and lower positions outside the frame 11d. .

The front and rear frame surfaces of the frame 11d are flat, and the sealing adhesive 1
By 2 it is in close contact with the edges of the glass substrate 7a and the transparent panel 8a, and the cooling layer 10 is sealed.

In addition, the cooling unit 8 has a bulge-like auxiliary cooling layer 10 in the upper and lower central portions.
a and 10a are integrally formed with the cooling layer 10, and the upper auxiliary cooling layer 10a collects bubbles when the cooling liquid 13 injected into the cooling layer 10 is heated to generate thermal convection. Yes. The auxiliary cooling layer 10a is provided with an appropriate number of endothermic fins 11b for speeding up the cooling of the cooling liquid 13. The auxiliary cooling layer 10a located below serves as a precipitation space for impurities.

Further, inside the frame 11d, the above-mentioned heat absorption fins 11c having a T-shaped cross section are provided along the inner wall 11e at the inner circumference avoiding the upper and lower auxiliary cooling layers 10a. The endothermic fins 11c serve not only to cool the cooling liquid 13 but also serve as a guide for circulating a part of the convection of the cooling liquid 13 that has generated heat convection downward.

The cooling liquid 13 is, for example, an ethylene glycol aqueous solution,
A cooling layer of the liquid crystal display device 1 that uses a liquid in which a dye such as an ink liquid that absorbs light other than a specific wavelength range in the light of the light source lamp 6 is dissolved, and makes the cooling liquid 13 colored by the dye correspond to three primary colors Used by injecting into 10. In this way, the color filter can be omitted in the projection of the color image.

FIG. 5 is an enlarged perspective view of portion B shown in FIG.

FIG. 6 shows a natural convection state of the cooling liquid 13 in the cooling layer 10. In the use of this liquid crystal display device 1, when the light 6a of the light source for the backlight is applied to the back surface of the liquid crystal display device 1 as shown in FIG. 1, heat from the light source or infrared rays contained in the light 6a First, in the liquid crystal display panel 7, the central portion A of the screen size 9 is heated. Then, due to this heating, natural convection occurs in the cooling liquid 13, and the cooling liquid 13 in the central portion A rises and reaches the upper region B together with the bubbles generated in the cooling liquid 13.

Since the auxiliary cooling layer 10a having the endothermic fins 11b is formed in the upper region B as described above, the cooling liquid 13 and bubbles rising therein are efficiently cooled by the auxiliary cooling layer 10a. Then, the cooling liquid 13 in the cooled upper region B
Is guided and lowered to both left and right regions by an inner wall-shaped heat absorption fin 11c provided so as not to return directly to the center of the cooling layer 10. Then, the cooling liquid 13 is added to this endothermic fin.
While being further cooled by 11c, it passes through the left and right passages C, reaches the lower region D where the lower auxiliary cooling layer 10a is located, and is further deprived of heat by the endothermic fins 11b in the lower region D to be cooled. After that, the cooling liquid 13 circulated in the lower region D again flows into the central region A by natural convection. The central part A
Since the temperature of the cooling liquid 13 in the other spaces is lower than that in the vicinity of the central portion A, natural convection occurs only in the cooling layer 10, and in the process of the convection, the endothermic fin 11c absorbs heat when descending along the inner surface thereof. The heat is taken away by the fin 11c and cooled.
Further, the cooling layer 10 is formed thin so that the flow velocity of natural convection can be obtained fast, and efficient cooling can be obtained.

FIG. 7 shows the transparent panel 8a of the cooling unit 8 shown in the above embodiment.
This is a case where the surface is further coated with the heat reflection film 14.
By doing so, the heat ray 6b included in the light 6a from the light source 6
Are reflected by the heat reflection film 14, and the liquid crystal display panel 7
It helps to further suppress the temperature rise of the liquid crystal material enclosed in.

Although the cooling unit 8 integrally attached to the liquid crystal display panel 7 is provided on the rear surface of the liquid crystal display panel 7 in the above embodiment, the cooling unit 8 is provided on the front surface of the liquid crystal display panel 7. Alternatively, it may be provided on both sides.

[Effects of the Invention] As described in detail above, according to the present invention, a cooler for cooling a liquid crystal display panel of a liquid crystal display device is provided in close contact with one surface side of the liquid crystal display panel, and a refrigerant is contained inside the cooler. Along with the cooling layer, a passage for circulating the refrigerant inside the cooler is provided outside the display area of the liquid crystal display panel around the cooling layer, so that the refrigerant is efficiently convected in the cooler. While cooling, it is possible to cool the liquid crystal display panel satisfactorily, and it is possible to avoid complication of the equipment.

[Brief description of drawings]

The drawings show an embodiment of the present invention, FIG. 1 is a plan view of a color liquid crystal projector device with a part thereof shown in cross section, FIG. 2 is a side view of the same as shown with a part thereof in cross section, and FIG. 3 is a front view. FIG. 4 is a front view of a liquid crystal display device showing a part of FIG. 3, FIG. 4 is a sectional view taken along line AA shown in FIG. 3, and FIG. 5 is an enlarged perspective view of a portion B shown in FIG. FIG. 7 is an explanatory view of natural convection of the cooling liquid in the cooling section, and FIG. 7 is a partial cross-sectional view of a transparent panel provided with a heat reflection film. 1 ... Liquid crystal display device, 7 ... Liquid crystal display panel, 8 ... Cooling part, 10 ... Cooling layer, 13 ... Cooling liquid.

Claims (1)

[Claims] 1. A liquid crystal display panel, and a cooler provided in close contact with one surface side of the liquid crystal display panel and having a cooling layer for containing a refrigerant therein. A liquid crystal display device, characterized in that a passage for circulating the refrigerant in the cooler is provided outside the display area of the liquid crystal display panel.