Patent Application
20060164568
This application claims priority to Korean Patent Application No. 2005-0007486, filed on Jan. 27, 2005 and all the benefits accruing therefrom under 35 U.S.C. §119, and the contents of which in its entirety are herein incorporated by reference.
1. Field of the Invention
The present invention relates, in general, to a light control plate and a liquid crystal display having the same and, more particularly, to a light control plate and a thin liquid crystal display which has the light control plate so as to realize uniform brightness.
2. Description of the Related Art
A liquid crystal display (“LCD”) includes a liquid crystal panel having a thin film transistor (“TFT”) substrate and a color filter substrate, and liquid crystals injected between both substrates. Since the LCD is a non-emitting device, it includes a backlight unit for providing light to a rear part of the TFT substrate. A transmissivity is controlled depending on an arrangement of the liquid crystals. The liquid crystal panel and the backlight unit are contained in a chassis.
Generally, the backlight unit includes a light source part for providing light onto the liquid crystal panel, and an optical member for reflecting or concentrating light provided from the light source part to enable light to be incident on the liquid crystal panel. The optical member mainly includes a diffusion plate, a diffusion sheet, a prism sheet, and a protective sheet.
The backlight unit may either be an edge-type or a direct-type depending on a position of the light source part.
The direct-type backlight unit has a structure that is suitable to enable the LCD to have a large size, and includes one or more light sources provided on a lower side of the liquid crystal panel, thereby providing light onto the entire liquid crystal panel. The direct-type backlight unit is advantageous in that, since a plurality of light sources can be used in comparison with the edge-type backlight unit, it is possible to assure high brightness.
However, the conventional LCD is problematic in that there is a difference in brightness between a plurality of channel parts onto which light is provided from the light source and non-channel parts which are formed between the channel parts, thus dark lines are formed on the liquid crystal panel. In other words, since brightness is non-uniform, a display quality is degraded.
Furthermore, since the optical member includes a plurality of layers, it becomes undesirably difficult to realize a thin liquid crystal display.
Accordingly, in an exemplary embodiment of the present invention, a light control plate and a thin liquid crystal display that includes the light control plate and assures uniform brightness is provided.
The foregoing and/or other aspects of the present invention are achieved by providing a light control plate including a base part and a first light dispersion part having a lenticular shape and combined with at least one side of the base part to disperse light provided from an exterior of the light control plate.
According to an exemplary embodiment of the present invention, the first light dispersion part has a radius of approximately 50 μm.
According to an exemplary embodiment of the present invention, the light control plate includes a plurality of first light dispersion parts, and a pitch between adjacent first light dispersion parts is approximately 100 μm.
According to an exemplary embodiment of the present invention, a plurality of first light dispersion parts are formed on the base part and the plurality of first light dispersion parts come into contact with each other.
According to an exemplary embodiment of the present invention, the plurality of first light dispersion parts is longitudinally extended across a surface of the base part.
According to an exemplary embodiment of the present invention, each first light dispersion part abuts an adjacent first light dispersion part.
According to an exemplary embodiment of the present invention, the base part includes a plurality of bubbles formed therein.
According to an exemplary embodiment of the present invention, the light control plate further includes an adhesive layer interposed between the base part and the first light dispersion part attaching the first light dispersion part to the base part.
According to an exemplary embodiment of the present invention, the adhesive layer includes a plurality of bubbles formed therein.
According to an exemplary embodiment of the present invention, a plurality of first light dispersion parts is randomly arranged on the base part.
According to an exemplary embodiment of the present invention, each first light dispersion part includes a circular-shaped protrusion projecting from the base part.
According to an exemplary embodiment of the present invention, a plurality of circular-shaped first light dispersion parts is evenly arranged on the base part.
According to an exemplary embodiment of the present invention, the plurality of circular-shaped first light dispersion parts is arranged in rows and columns on the base part.
According to an exemplary embodiment of the present invention, the light control plate further includes a second light dispersion part combined with at least one side of the base part and having a shape of a prism, and the first light dispersion part and the second light dispersion part are longitudinally formed in plural on the base part.
According to an exemplary embodiment of the present invention, the first light dispersion parts are formed on both sides of the base part.
According to an exemplary embodiment of the present invention, the first light dispersion part is formed on a first side of the base part, and a second light dispersion part is formed on a second and opposite side of the base part, the second light dispersion part having a different shape than the first light dispersion part.
The foregoing and/or other aspects of the present invention are also achieved by providing a liquid crystal display including a liquid crystal panel on which an image is formed, a light source part for providing light to the liquid crystal panel, and a light control plate provided between the liquid crystal panel and the light source part and comprising a base part and a light dispersion part, is the light dispersion part having a lenticular shape and combined with the base part to disperse light provided from the light source part.
According to an exemplary embodiment of the present invention, the light source part is provided behind the light control plate, and includes any one of a flat light source lamp, a line light source lamp, and a point light source lamp.
According to an exemplary embodiment of the present invention, the light source part is between approximately 5 and approximately 15 mm from the light control plate.
According to an exemplary embodiment of the present invention, a plurality of light dispersion parts are formed on the base part and the plurality of light dispersion parts come into contact with each other.
According to an exemplary embodiment of the present invention, the base part includes a plurality of bubbles formed therein.
According to an exemplary embodiment of the present invention, the liquid crystal display further includes an adhesive layer interposed between the base part and the light dispersion part attaching the light dispersion part to the base part.
According to an exemplary embodiment of the present invention, the adhesive layer includes a plurality of bubbles formed therein.
According to an exemplary embodiment of the present invention, the light control plate includes any one of acryl and polycarbonate.
According to an exemplary embodiment of the present invention, the liquid crystal display further includes a diffusion sheet provided on the light control plate to diffuse light passing through the light control plate.
According to an exemplary embodiment of the present invention, the first light dispersion part has a radius of approximately 50 μm.
According to an exemplary embodiment of the present invention, the light control plate includes a plurality of first light dispersion parts, and a pitch between adjacent first light dispersion parts is approximately 100 μm.
The foregoing and/or other aspects of the present invention are also achieved by providing a backlight assembly including a light source part providing light and a light control plate penetrated by the light, the light control plate including a base part and a lenticular shaped light dispersion part combined with the base part to disperse the light provided by the light source part.
According to an exemplary embodiment of the present invention, a plurality of lenticular shaped light dispersion parts extend longitudinally across a surface of the base part, and each light dispersion part abuts an adjacent light dispersion part.
According to an exemplary embodiment of the present invention, a plurality of prism shaped light dispersion parts are alternatingly arranged with the plurality of lenticular shaped light dispersion parts.
According to an exemplary embodiment of the present invention, a plurality of light dispersion parts are dispersed across a surface of the base part, and each light dispersion part includes a circular-shaped projection.
According to an exemplary embodiment of the present invention, a plurality of light dispersion parts are arranged across a first surface of the base part facing the light source part and a plurality of light dispersion parts are arranged across a second surface of the base part facing away from the light source part.
Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures. In the drawings, the thickness of layers, films, and regions are exaggerated for clarity. It will be understood that when an element such as a layer, film, region, or substrate is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present.
The base part 110 is typically transparent and made of an acryl-based resin, such as, but not limited to, polymethylmethacrylate (“PMMA”) or polycarbonate (“PC”) having excellent light transmittance.
A plurality of first light dispersion parts 120 is formed on the base part 110 so as to come into contact with each other. That is, where one first light dispersion part 120 ends, another first light dispersion part 120 begins, such that each first light dispersion part 120 is in abutting relationship with any adjacent first light dispersion part 120. In one embodiment, the radius of each light dispersion part 120 is about 50 μm and the pitch there between is about 100 μm. The first light dispersion parts 120 are formed on one side of the base part 110, and function to disperse light provided from the an exterior of the light control plate 100. That is, the first light dispersion parts 120 disperse light to make brightness of light uniform. The lenticular shape of the first light dispersion parts assists in the dispersion of light. It should be understood, with reference to the drawings, that the lenticular shape refers to the shape that is shaped like a lens, and includes an array of optical surfaces, such as a number of lenses closely packed. As illustrated, the optical surfaces include a plurality of convex surfaces. It is preferable to simplify a process of manufacturing the light control plate 100 by integrally injection molding or extruding the first light dispersion parts 120 in conjunction with the base part 110. However, production of the first light dispersion parts 120 is not limited to the above description, and the first light dispersion parts 120 may alternately be formed using an ultraviolet curable resin. That is, after the ultraviolet curable resin is applied on one side of the base part 110, the base part 110 is passed through a roller that is wound by a lenticular pattern. Next, ultraviolet rays are irradiated on a lenticular side to cure the ultraviolet curable resin. While particular methods for forming the light control plate 100 are described, other methods of forming the light control plate 100 would also be within the scope of these embodiments. In the illustrated embodiment, the first light dispersion parts 120 are formed on only one side of the base part 110. Alternatively, the first light dispersion parts 120 may be formed on both sides of the base part 110.
The base part 210 may be formed using, by example, an acryl-based resin or PC and a blowing agent mixed together. The blowing agent generates gas at a predetermined temperature or higher to form the bubbles 215. Accordingly, light provided from an exterior of the light control plate 200 is scattered by the bubbles 215, and then dispersed by the first light dispersion parts 120. In other words, the bubbles 215 scatter light penetrated into the base part 210. As in the prior embodiment described with respect to
It is preferable that the light control plate 300 further includes an adhesive layer 130 for attaching the first light dispersion parts 120 to the base part 210 and is applied between the base part 210 and the first light dispersion parts 120. As in the second embodiment described with respect to
The adhesive layer 130 is formed by mixing an adhesive and a blowing agent, and has a plurality of bubbles 135 generated by the blowing agent therein. The adhesive layer 130 unites the base part 210 with the first light dispersion parts 120 and scatters light using the bubbles 135 thereof. As in the prior embodiments described with respect to
While the first light dispersion parts 120 are shaped as having a length extending from a first side of the light control plate 100 to an opposite side of the light control plate 100, the first light dispersion parts 410 are instead shaped as bumps, projections, convex protrusions, or the like. Any shape capable of effectively dispersing light penetrating the base part 410 would be within the scope of these embodiments. Although not illustrated in
That is, a plurality of lenticular shaped first light dispersion parts 120 and a plurality of prism-shaped second light dispersion parts 150 are longitudinally formed on a base part 110, such as by extending from a first side to an opposite side of the light control plate 500. The first light dispersion parts 120 and the second light dispersion parts 150 are illustrated as regularly arranged, however the arrangement is not limited to the above description, and may be variously modified as long as it effectively disperses light. By example only, one or more first light dispersion parts 120 may be alternatingly arranged with one or more second light dispersion parts 150.
Although not illustrated in
The light control plate capable of uniformly dispersing light is provided using the above-mentioned constitution, such as described with reference to
Hereinafter, a detailed description will be given of a liquid crystal display (“LCD”) according to the present invention, referring to the accompanying drawings.
The liquid crystal panel 510 comprises a thin film transistor (“TFT”) substrate 511 on which a TFT is formed, a color filter substrate 512 which is opposite the TFT substrate 511, and a liquid crystal layer (not shown) interposed between both substrates. The liquid crystal panel 510 forms images depending on an arrangement of liquid crystal molecules within the liquid crystal layer. Since the liquid crystal panel 510 is a non-emitting device, the backlight unit 550 is required.
Driving signals which are supplied from the source PCB 580 and the gate PCB 590 are applied through data flexible circuit films 585 and gate flexible circuit films 595 to the liquid crystal panel 510. Data driving chips 586 and gate driving chips 596 are mounted on the data flexible circuit films 585 and the gate flexible circuit films 595, respectively, to apply the driving signals, which are supplied from the source PCB 580 and the gate PCB 590, to the liquid crystal panel 510.
The chassis 600 includes a lower chassis 620 provided below the backlight unit 550 for receiving the backlight unit 550, a mold frame 630 provided on the backlight unit 550 to support the liquid crystal panel 510 so that the liquid crystal panel 510 is safely mounted thereon, and an upper chassis 610 provided on the liquid crystal panel 510 so as to be combined with the lower chassis 620.
The backlight unit 550 includes light source parts 551 for providing light onto the liquid crystal panel 510, and a light control plate 100 provided on the light source parts 551 to disperse light provided from the light source parts 551 onto the liquid crystal panel 510. The backlight unit 550 may further include a diffusion sheet (not shown) provided on the light control plate 100 to diffuse light penetrated into the light control plate 100.
The light source parts 551 are provided behind the light control plate 100 such that the light source parts 551 are positioned between the lower chassis 620 and the light control plate 100. The light source parts 551 may be any one of a flat light source lamp, such as a flat fluorescent lamp (“FFL”), a line light source lamp, such as a cold cathode fluorescent lamp (“CCFL”), or a point light source lamp, such as an light emission diode (“LED”). In the illustrated embodiment, the FFL is used although it should be understood that other light source parts 551 may be incorporated into the LCD.
The FFL of the light source parts 551 includes a channel part 552 (
Light is provided from the channel part 552 of the FFL of the light source parts 551 onto the liquid crystal panel 510 after being dispersed by the light control plate 100. Accordingly, with respect to light provided onto the liquid crystal panel 510, a difference in brightness of the channel part 552 and the non-channel part 553 is reduced due to the light control plate 100, thus assuring uniform brightness, and thereby improving display quality.
As further shown in
As previously described, the light control plate 100 includes a base part 110 and first light dispersion parts 120 on the base part 110. The first light dispersion parts 120 are lenticular shaped and disperse light provided from an exterior of the light control plate 100, such as from the light source parts 551. The light control plate 100 is provided so that the first light dispersion parts 120 face upward herein, such as towards the liquid crystal panel 510. Alternatively, the first light dispersion parts 120 may face downward, such as towards the light source parts 551. In yet another alternative embodiment, the first light dispersion parts 120 may be provided on the base part 110 such that there are first light dispersion parts 120 that face both upwardly and downwardly. Since the light control plate 100 is the same as that of
Light from the channel parts 552 of the FFL of the light source parts 551 is provided to the first light dispersion parts 120 through the base part 110 of the light control plate 100. Since the first light dispersion parts 120 are lenticular, it is possible to infinitely disperse the light transmitted there through. Accordingly, boundaries between the channel parts 552 and the non-channel parts 553 become vague and blurred, thus removing dark lines that would otherwise be caused by the non-channel parts 553. Therefore, light from the FFL of the light source parts 551 is provided to the liquid crystal panel 510 after being dispersed by the first light dispersion parts 120, thereby providing the LCD with uniform brightness.
As shown in
In the above-mentioned description, the LCDs having the light control plates according to the first embodiment and the second embodiment are disclosed. Alternatively, an LCD having light control plates according to the third to fifth embodiments, as well as variations thereof, may also be provided.
In the above-mentioned description, the light dispersion parts are formed on an upper side of the base part, that is, facing the liquid crystal panel. Alternatively, the light dispersion parts may be formed on a lower side of the base part, such as by facing the light source parts, or on both sides of the base part facing both the light source parts and the liquid crystal panel. Meanwhile, if the light dispersion parts are formed on both sides of the base part, its shape may be made different. For example, light dispersion parts on an uppers side of the base part may be different from light dispersion parts on a lower side of the base part. Alternatively, the upper and lower side light dispersion parts may have the same shape or may be mirror images of each other.
As described above, the present invention provides a thin LCD capable of assuring uniform brightness.
Although a few embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms an, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2005-0007486 | Jan 2005 | KR | national |
