Patent Application
20070297188
The above and other features and advantages of the present invention will become more apparent by describing in detailed exemplary embodiments thereof with reference to the exemplary embodiments thereof with reference to the attached drawings in which:
Exemplary embodiments of the invention are described more fully hereinafter with reference to the accompanying drawings. This invention may, however, be embodied in many different forms without departing from the inventive principles disclosed herein, and the scope of the present invention should not be construed as being limited to these following embodiments. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the invention to those skilled in the art by way of example and not of limitation.
It will be understood that when an element or layer is referred to as being “on,” “connected to” or “coupled to” another element or layer, it can be directly on, connected or coupled to the other element or layer or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers present. Like numbers refer to like elements throughout. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.
Spatially relative terms, such as “below”, “lower”, “above”, “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the exemplary term “below” can encompass both an orientation of above and below.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
Referring to
The LC panel 10 includes a color filter substrate 11 and a thin film transistor (“TFT”) substrate 12 which are disposed opposite to each other and facing each other with a liquid crystal layer interposed therebetween.
The color filter substrate 11 includes a black matrix for preventing light from being leaked, a color filter for expressing various colors, a common electrode for forming a vertical electric field with a pixel electrode arranged on the TFT substrate 12 and an alignment layer for aligning the liquid crystals. In an exemplary embodiment, the color filter substrate 11 may be made of transparent insulating material such as glass or plastic.
The TFT substrate 12 includes gate lines and data lines, which are formed to cross each other, the TFTs formed at the intersections of the gate lines and the data lines, a pixel electrode contacting the TFTs, and an alignment layer for aligning the liquid crystals. In an exemplary embodiment, the TFT substrate 12 may be made of a transparent insulating material such as glass or plastic.
The panel driving portion 20 is connected to one side of the LC panel 10 and supplies a driving signal to the gate and data lines of the LC panel 10. The panel driving portion 20 includes a gate driving portion for driving the gate lines, a data driving portion for driving the data lines, a timing control portion for supplying a control signal and an image signal to the gate and data driving portions and a power source portion for supplying an electric power to the gate and data driving portions.
The gate driving portion is formed such that a gate driving circuit is mounted on a tape carrier package (“TCP”) 23. The TCP 23 is disposed between the printed circuit board (“PCB”) and the LC panel 10. In an exemplary embodiment, the TCP 23 may be mounted on the TFT substrate 12 by use of the chip on glass (“COG”) method or may be integrated on the TFT substrate 12
The data driving portion may be formed such that one side of the data TCP 23 having a data driving circuit 22 mounted thereon may be connected to the PCB 21. A timing controller and the power source portion are mounted on the PCB 21 so that the timing controller and the power source portion may supply the data driving circuit 22 with the control signal, the image signal and the power signal. In an exemplary embodiment, the data TCP 23 may be flexible so that the TCP 23 may be bent to surround one side of the mold frame 30 while the PCB 21, which may be connected to the data TCP 23, may be placed on a bottom surface of the mold frame 30.
The mold frame 30 may be formed to have a step portion in its inner sidewall. The mold frame 30 accommodates and holds the backlight assembly thereinside. The step portion formed in the inner sidewall in the mold frame 30 may support and hold the LC panel 10. The mold frame 30 includes a groove formed to protect the data driving circuit 22 mounted on the data TCP 23 from external force. In an exemplary embodiment, a step portion may be formed on the bottom surface of the mold frame 30 so that the step portion may hold the PCB 21.
The bottom chassis 50 supports and holds the backlight assembly, the LC panel 10, the data TCP 23 and the PCB 21, which are accommodated and held by the mold frame 30.
The top chassis 60 may be coupled to the bottom chassis 50 and may surround a non-display area of an edge or peripheral area of a front surface of the LC panel 10 and the mold frame 30. The bottom chassis 50 and the top chassis 60 coupled to each other tightly holds the LC panel 10 and absorbs an external impact to protect the LC panel 10, the backlight assembly, and the panel driving portion 20.
The backlight assembly includes a light guide plate 44 for guiding light, a plurality of LEDs 45 formed below the light guide plate 44 to overlap at least a portion of the light guide plate to emit light to one side of the light guide plate 44, a reflecting plate 47 for reflecting light emitted from the LEDs 45 to direct light to an incident surface of the light guide plate 44, a reflecting sheet 48 for reflecting light supplied to a lower portion of the light guide plate 44 upwardly and optical sheets 41, 42 and 43 formed on the light guide plate 44 to improve light efficiency.
The optical sheets 41, 42 and 43 are formed on the light guide plate 44 to provide incident rays of the light emitted from the upper portion of the light guide plate 44 on the LC panel 10. The optical sheets 41, 42 and 43 allow the incident light from the light guide plate 44 to be vertically incident on the LC panel 10, thereby improving light efficiency. An exemplary embodiment of the optical sheets 41, 42 and 43 may include a protecting sheet 41, a prism sheet 42, and a diffusion sheet 43.
The diffusion sheet 43 allows the light emitted from the light guide plate 44 to face towards the LC panel 10, diffuses the light so that a uniform light distribution may be provided in a relatively wider range and provides incident rays to the LC panel 10. In an exemplary embodiment, the diffusion sheet 43 may be made of a transparent resin film whose both sides are coated with a light diffusing material. The prism sheet 42 converts a moving angle of light diffused by the diffusion sheet 43 to be vertical to the LC panel 10. The vertical angle between the light from the diffusion sheet 43 and the LC panel 10 may maximize light efficiency. The protecting sheet 41 diffuses light passing through the prism sheet 42 while protecting a surface of the prism sheet 42.
The reflecting sheet 48 arranged on a bottom surface of the light guide plate 44 reflects the light emitted to the lower portion of the light guide plate 44 toward the upper portion of the light guide plate 44. In an exemplary embodiment, the reflecting sheet 48 may be made of a sheet having high reflectivity.
The light guide plate 44 converts a line-shaped light supplied through its incident surface into a surface-shaped light and guides the surface-shaped light to the LC panel 10. The light guide plate 44 may have a plurality of V-shaped grooves or projections for directing light from the incident surface 144 to an opposite side surface.
In an exemplary embodiment, the LEDs 45 may be mounted on a light source substrate 46 at a substantially uniform interval and may be driven by the driving signal supplied through the light source substrate 46 to generate light.
In an exemplary embodiment, the light source substrate 46 may be realized by a flexible printed circuit (“FPC”) or a PCB. The light source substrate 46 may be formed in the form of a long bar and may be connected to an electrical power source and an area on which the LEDs 45 are mounted. Electrodes are formed at both ends of the light source substrate 46 so that a driving power may be provided to the LEDs 45. The light source substrate 46, as shown in
The LED pad 152 may be made of conductive metal and may be formed in an area on which the LEDs 45 may be mounted. The heat releasing pad 151 may be connected to the LED pad 152. Such structure allows radiation of heat generated in the LEDs 45 to the external portion through the LED pad 152 and the heat-releasing pad 151.
As shown in
Light emitted from the LEDs 45 may be directed to the incident surface 144 formed on at least one side of the light guide plate 44. The reflecting plate 47 may be disposed to face both a light emitting surface of the LEDs 45 and the incident surface 144 of the light guide plate 44.
The reflecting plate 47 directs light emitted from the LEDs 45 to the incident surface 144 of the light guide plate 44. The reflecting plate 47, as shown in
The semi-pillar shaped groove 147 of the reflecting plate 47 reflects light through a reflecting surface 148. As shown in
The LEDs 45 may overlap at least a portion of the reflecting sheet 48. After the reflecting sheet 48 is formed below the light guide plate 44, the light source substrate 46 on which the LEDs 45 are mounted may be formed at an area adjacent to the incident surface 144 of the light guide plate 44 on the reflecting sheet 48. Thus, when light emitted from the LEDs 45 is incident on the incident surface 144 of the light guide plate 44, light directed to the lower portion of the incident surface 144 of the light guide plate 44 may be reflected upwardly by the reflecting sheet 48, thereby further improving light efficiency.
In an exemplary embodiment, the LEDs 45, the PCB 21 and the data TCP 23 are disposed at the bottom surface of the light guide plate 44. In the exemplary embodiment, the thickness of the backlight assembly increases due to the thickness of the LEDs 45. However, because the PCB 21 and the data TCP 23 have a greater thickness than that of the LEDs 45, the total thickness of the backlight assembly does not increase. Instead, according to the exemplary embodiment, the thickness of the LCD device can be reduced by a sum of the distance between the LEDs 45 and the light guide plate 44 and the length of the LEDs 45 compared to a conventional LCD device. Since the size of the mold frame 30, the bottom chassis 50 and the top chassis 60 can be reduced the weight of the LCD device can be correspondingly reduced.
The LCD device shown in
The LEDs 45, as shown in
In addition, the transmission of heat generated in the LEDs 45 to the light guide plate 44 through the light source substrate 46 reduces or effectively prevents the LEDs 45 from being overheated and thus leads to a higher display quality.
In another exemplary embodiment, the light path emitted from the LEDs 45 has the same length as shown in
In an exemplary embodiment, an LCD device includes a plurality of LEDs arranged on or below the light guide plate allowing a size and weight of the LCD device to be reduced.
In an exemplary embodiment, the length of the path of light emitted from the LEDs is increased by the reflecting plate, thereby preventing the white spot phenomenon in the display area and leading to the high display quality.
In an exemplary embodiment, the light source substrate having the LEDs may be attached to the bottom chassis or the light guide plate, so that the heat generated in the LEDs may be transmitted to the bottom chassis or the light guide plate. Accordingly, the LCD device may be prevented from being overheated, and a result, a higher display quality may be reached.
Although the present invention has been described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that a variety of modifications and variations may be made to the present invention without departing from the spirit or scope of the present invention defined in the appended claims, and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1020060056231 | Jun 2006 | KR | national |
