This application claims priority from and the benefit of Korean Patent Application No. 10-2014-0163586, filed on Nov. 21, 2014 which is hereby incorporated by reference for all purposes as if fully set forth herein.
1. Field
Exemplary embodiments relates to a liquid crystal display (LCD).
2. Discussion
Liquid crystal displays (LCDs) are a type of flat panel display. From a high-level perspective, an LCD includes a pair of substrates, having electric field generating electrodes such as pixel electrodes and a common electrode, and a liquid crystal layer interposed between the substrates. To display an image on the LCD, voltages are applied to the electric field generating electrodes in the LCD to generate an electric field in the liquid crystal layer, which determines the alignment of liquid crystal molecules of the liquid crystal layer and controls the polarization of incident light.
If an electric field in one direction is applied to the liquid crystal layer for a long time, problems such as degradation or flickering may arise. To prevent or reduce the problems, the LCD can invert the polarity of a driving data voltage (with respect to a common voltage), for portions of the display, such as particular frames, rows, columns, or pixels. An example of such inversion driving is a 2-dot inversion driving method in which two pixels form an inversion unit, where pixels in an odd-numbered row and a pixels in an even-numbered row of the same column are driven with a data voltage of the same polarity.
Because pixels neighboring an inversion unit can be driven with a driving voltage of an opposite polarity when driving a frame, signals of different polarities can be applied on both sides of a data line for an inversion unit, such as a group of two rows in a 2-dot inversion driving. Here, a distance between the data line and each of pixel electrodes in first and second rows may be different from a distance between the data line and each of pixel electrodes in third and fourth rows. Although the distance between the data line and each pixel electrode should be equal, it may be different due to occurrence of a misalignment. Such a relative difference in distance between the data line and pixel electrodes in different inversion units may lead to a difference in parasitic capacitance (Cdp) between each pixel electrode and the data line, causing a horizontal line defect which may degrade display quality.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept, and, therefore, it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
Exemplary embodiments provide a liquid crystal display (LCD) without a horizontal line defect caused by a difference in parasitic capacitance (Cdp).
Additional aspects will be set forth in the detailed description which follows, and, in part, will be apparent from the disclosure, or may be learned by practice of the inventive concept.
According to one or more exemplary embodiments, there is provided a liquid crystal display (LCD) comprising a first pixel electrode portion; a second pixel electrode portion disposed adjacent to the first pixel electrode portion in a first direction; and a first data line, extending substantially in a second direction, configured to apply a data voltage to the first pixel electrode portion; wherein the data line comprises a first line portion overlapping the first pixel electrode portion and a second line portion overlapping the second pixel electrode portion.
According to one or more exemplary embodiments, there is provided an LCD comprising
a first pixel electrode portion; a first data line, extending substantially in a first direction, configured to apply a data voltage to the first pixel electrode portion; and a second data line, extending substantially in a first direction, disposed adjacent to the first data line in a second direction, wherein a portion of the first data line overlaps the first pixel electrode portion along a side area of the first pixel electrode portion, and a portion of the second data line overlaps the first pixel electrode along an opposite side area of the first pixel electrode.
According to one or more exemplary embodiments, there is provided an LCD comprising a first pixel electrode portion, a second electrode portion disposed adjacent to the first pixel electrode along a first direction and a first data line extending along a second direction substantially perpendicular to the first direction, wherein the first data line overlaps the first pixel electrode portion and the second pixel electrode portion.
The foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the claimed subject matter.
The accompanying drawings, which are included to provide a further understanding of the inventive concept, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the inventive concept, and, together with the description, serve to explain principles of the inventive concept.
In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various exemplary embodiments. It is apparent, however, that various exemplary embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring various exemplary embodiments.
In the accompanying figures, the size and relative sizes of components, etc., may be exaggerated for clarity and descriptive purposes. Also, like reference numerals denote like elements.
When a component is referred to as being “on,” “connected to,” or “coupled to” another component, it may be directly on, connected to, or coupled to the other component or intervening components may be present. When, however, a component is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another component, there are no intervening components present. For the purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” may be construed as X only, Y only, Z only, or any combination of two or more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ. 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.
Although the terms first, second, etc. may be used herein to describe various features, these features should not be limited by these terms. These terms are used to distinguish one feature from another. Thus, a first feature could be termed a second feature without departing from the teachings of the present disclosure.
Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for descriptive purposes, and, thereby, to describe one feature's relationship to another feature as illustrated in the drawings. Spatially relative terms are intended to encompass different orientations of an apparatus in use, operation, and/or manufacture in addition to the orientation depicted in the drawings. For example, if the apparatus in the drawings 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. Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and, as such, the spatially relative descriptors used herein interpreted accordingly.
The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. 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. Moreover, the terms “comprises,” comprising,” “includes,” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
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 disclosure is a part. 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 will not be interpreted in an idealized or overly formal sense, unless expressly so defined herein.
Referring to
Scan lines may extend along a first direction D1, parallel to each other. Scan lines may sequentially provide a scan signal to transistor TR of each pixel PX.
Data lines may intersect the scan lines. A data voltage may be provided to each of data lines. The data voltage may be provided to pixel electrode P via turned-on transistor TR. Data lines may have a zigzag shape. Accordingly, data lines may, overall, extend along a second direction D2 perpendicular to the first direction D1. Here, the first direction D1 may be a row direction and the second direction D2 may be a column direction. Data lines DL may be bent repeatedly. In exemplary embodiments, vertical portions in a first direction (in a direction D2) are provided on alternate sides of a virtual line along the first direction and portions in a second direction (in a direction D1) connect the alternating portions. For example, each of data lines DL1, DL2, DL3, etc. may include lines extending on different vertical lines along the second direction D2 and lines extending along the first direction D1 which are connected to each other as illustrated in
A data line which supplies a data voltage to pixel PX is defined as a self-data line, and a pixel electrode which receives a data voltage of a data line is defined as a self-pixel electrode. Each pixel PX may partially overlap the self-data line and overlap a data line disposed side by side with the self-data line along first direction D1. More specifically, pixel electrode P of each pixel PX may overlap the self-data line and a neighboring data line. Pixel electrode P may include a first side along the first direction D1 and a second side along the second direction D2. Here, pixel electrode P may overlap the self-data line by a length corresponding to substantially half of the second side. Pixel electrode P may overlap an immediately neighboring data line by a length corresponding to substantially the other half of the second side.
From the perspective of a data line, a single data line may overlap all neighboring pixel electrodes in two columns of pixels. For example, the data line may overlap a pixel electrode disposed on one side thereof and a pixel electrode disposed on the other side thereof. The positional relationship between pixel electrodes and a data line will now be described in greater detail with reference to
Referring to
Second data line DL2 may include first line L1 which overlaps first pixel electrode P1 and second line L2 which overlaps second pixel electrode P2. Second data line DL2 may further include third line L3 which connects first line L1 and second line L2. First line L1 and second line L2 may extend along second direction D2, and third line L3 may extend along first direction D1. Each of first pixel electrode P1 and second pixel electrode P2 may include a first side corresponding to first direction D1 and a second side corresponding to second direction D2. In addition, each of first pixel electrode P1 and the second pixel electrode P2 may be bisected by a virtual line CL that traverses a center thereof along first direction D1. First line L1 may overlap an upper part of bisected first pixel electrode P1, and second line L2 may overlap a lower part of bisected second pixel electrode P2. However, aspects of the present invention are not limited thereto. In exemplary embodiments, first line L1 may overlap a lower part of first pixel electrode P1, and second line L2 may overlap an upper part of second pixel electrode P1.
Second data line DL2 overlaps each of pixel electrodes P1 and P2. Storage line SL may be disposed in a boundary area between the first pixel electrode P1 and the second pixel electrode P2, which will be described in greater detail below.
From the perspective of a pixel electrode, an upper electrode of first pixel electrode P1 may overlap first line L1 of second data line DL2, and a lower electrode of first pixel electrode P1 may overlap second line L2 of first data line DL1. In addition, an upper electrode of second pixel electrode P2 may overlap first line L1 of third data line DL3, and a lower electrode of second pixel electrode P2 may overlap second line L2 of second data line DL2. One pixel electrode may form parasitic capacitance Cdp of a specific level together with each of a self-data line and an immediately neighboring data line. One pixel electrode may form the parasitic capacitance Cdp together with each data line that it overlaps. Here, one pixel electrode may form the parasitic capacitance Cdp together with each of diagonally symmetrical data lines having different polarities. Accordingly, the parasitic capacitance Cdp generated in one pixel electrode can be minimized.
Each of first line L1 and second line L2 may be separated by a predetermined distance “a” from the boundary area between first pixel electrode P1 and second pixel electrode P2. First line L1 may be separated from the boundary area between first pixel electrode P1 and second pixel electrode P2 by the predetermined distance a to overlap first pixel electrode P1. Second line L2 may be separated from the boundary area between first pixel electrode P1 and second pixel electrode P2 by the predetermined distance a to overlap second pixel electrode P2. Here, the predetermined distance a may be a distance at which first line L1 does not form the parasitic capacitance Cdp with second pixel electrode P2 and at which second line L2 does not form the parasitic capacitance Cdp with first pixel electrode P1. The predetermined distance “a” may be a maximum error distance set in view of the possible misalignment of a data line. Even if second data line DL2 is misaligned, entire first line L1 may still overlap first pixel electrode P1. The effects of the data line structure according to one or more exemplary embodiments will now be described in greater detail with reference to
Referring to
Referring to
First substrate S1 may be an insulating substrate, on which the pixel electrodes P1 and P2 are formed or disposed. Second substrate S2 may face first substrate S1 and may be a substrate on which the common electrode CE is formed or disposed. Pixel electrodes P1 and P2 and common electrode CE may form a vertical electric field. However, aspects of the present invention are not limited thereto, and common electrode CE can also be formed or disposed on the same layer as or a different layer from pixel electrodes P1 and P2 on first substrate S1 to form a horizontal electric field. The arrangement of liquid crystals included in liquid crystal layer LC between first substrate S1 and second substrate S2 may change according to an electric field formed by pixel electrodes P1 and P2 and common electrode CE. Here, data voltages may be applied to first and second pixel electrodes P1 and P2 via first data line DL1 and second data line DL2 as described above, and a specific common voltage may be applied to common electrode CE. A backlight (not illustrated) may be disposed under first substrate S1 and emit light in an upward direction. The arrangement of the liquid crystals in liquid crystal layer LC may vary according to a difference between the common voltage and a data voltage. That is, the luminance of backlight that passes through liquid crystal layer LC may be controlled by a change in the arrangement of the liquid crystals in liquid crystal layer LC.
A scan line (not illustrated) and storage line SL may be formed or disposed on the first substrate S1. Storage line SL may provide a specific voltage to each storage electrode which forms an electric field with a pixel electrode. The storage electrode (not illustrated) may overlap edges of each pixel electrode, but aspects of the present invention are not limited thereto. Storage line SL may be formed to correspond to a boundary between pixel electrodes. That is, storage line SL may have a cross-sectional area corresponding to a gap between the pixel electrodes. A width of storage line SL may be substantially equal to the distance between the boundaries of first pixel electrode P1 and second pixel electrode P2. Since storage line SL is disposed to correspond to the boundary between the first pixel electrode P1 and the second pixel electrode P2, the leakage of light which may occur when no data line passes through the boundary between the first pixel electrode P1 and the second pixel electrode P2 may be prevented or reduced.
First insulating layer I1 may be formed or disposed on first substrate S1, the scan line (not illustrated), and storage line SL. First insulating layer I1 may be a gate insulating layer and may electrically insulate the scan line (not illustrated) and storage line SL from components formed or disposed on first insulating layer I1.
A data line may be formed or disposed on first insulating layer I1. For example, first line L1 may be formed or disposed on first insulating layer I1. Color filters C1 and C2 may be formed on first line L1 and first insulating layer I1. In LCD 10 according to one or more exemplary embodiments, color filters C1 and C2 may be formed or disposed on first substrate S1. First color filter C1 may be formed or disposed to correspond to first pixel electrode P1. First color filter C1 may include one of red, green, and blue colors. Second color filter C2 may be formed or disposed to correspond to second pixel electrode P2 neighboring first pixel electrode P1. Second color filter C2 may produce a different color from first color filter C1. First color filter C1 and second color filter C2 may overlap each other between first pixel electrode P1 and second pixel electrode P2. By placing color filters C1 and C2 on lower substrate S1, the leakage of light caused when no data line overlaps the boundary between the first pixel electrode P1 and the second pixel electrode P2 may be prevented or reduced. LCD 10 according to one or more exemplary embodiments may not require a black matrix because storage line SL and color filters C1 and C2 are formed or disposed at the boundary between first pixel electrode P1 and second pixel electrode P2. Accordingly, the overall thickness of LCD 10 can be reduced. Second insulating layer I2 may be formed or disposed on color filters C1 and C2 and may be a planarization layer. Pixel electrodes P1 and P2 may be formed or disposed on second insulating layer I2.
First line L1 may overlap first pixel electrode P1. First line L1 may be separated by a predetermined distance “a” from the boundary between first pixel electrode P1 and second pixel electrode P2. The predetermined distance “a” may be a distance at which first line L1 does not form parasitic capacitance with second pixel electrode P2. First line L1 may form parasitic capacitance Cdp1 only with first pixel electrode P1. For example, first pixel electrode P1 may form parasitic capacitance with first line L1 of second data line DL2 and may form parasitic capacitance with second line L2 of first data line DU. The predetermined distance “a” may be a maximum error distance set in view of the possible misalignment of a data line. Even if second data line DL2 is misaligned along first direction D1, entire first line L1 may still overlap first pixel electrode P1. Referring to
Likewise, second line L2 may overlap second pixel electrode P2 and may be separated by a predetermined distance “a” from the boundary between first pixel electrode P1 and second pixel electrode P2. The predetermined distance “a” may be a distance at which second line L2 does not form parasitic capacitance with first pixel electrode P1. Second line L2 may form parasitic capacitance Cdp2 only with second pixel electrode P2. The predetermined distance “a” may be a maximum error distance set in view of the possible misalignment of a data line. Even if second data line DL2 is misaligned along, e.g., the reverse direction of first direction D1, the entire second line L2 may still overlap second pixel electrode P2. Referring to
Parasitic capacitance formed by a pixel electrode and a data line according to one or more exemplary embodiments may have a constant value despite the misalignment of the data line. Accordingly, even if the 2-dot inversion method is used, there may be no substantial change in the parasitic capacitance in an inversion unit. This may prevent or reduce a horizontal line defect, thus providing a more improved display quality.
Referring to
Each pixel electrode according to one or more exemplary embodiments may include a first subpixel electrode and a second subpixel electrode. Different voltages may be applied to the first subpixel electrode and the second subpixel electrode in order to improve a viewing angle, and the first subpixel electrode and the second subpixel electrode may display one image. A self-data line of each pixel electrode may overlap a half of the first subpixel electrode and a half of the second subpixel electrode. In addition, a data line immediately neighboring the pixel electrode may overlap the other half of the first subpixel electrode and the other half of the subpixel electrode. The data line structure of one or more exemplary embodiments may also be applied to the LCD driven using the first subpixel electrode and the second subpixel electrode.
Referring to
Scan lines may extend along first direction D1. Scan lines may extend parallel to each other. Scan lines may sequentially provide a scan signal to transistor TR of each pixel PX.
Data lines may intersect scan lines and may extend along second direction D2 perpendicular to first direction D1. A data voltage may be provided to each of the data lines.
One data line may overlap specific areas of neighboring pixels. Referring to
First pixel electrode P1 and second pixel electrode P2 may be arranged side by side along first direction D1. Third area a3 of first pixel electrode P1 may be formed or disposed adjacent to a non-protruding part of the first side of first area a1 of the second pixel electrode P2. In addition, second area a2 of second pixel electrode P2 may be disposed adjacent to a non-iii protruding part of the second side of first area a1 of first pixel electrode P1. A boundary area between first pixel electrode P1 and second pixel electrode P2 may have a zigzag shape, in which the boundary between the first pixel electrode P1 and the second pixel electrode P2 may be bent repeatedly. Second data line DL2 may overlap third area a3 of first pixel electrode P1 and second area a2 of second pixel electrode P2. Second data line DL2 may not be formed or disposed along the boundary area between first pixel electrode P1 and second pixel electrode P2. Each data line may form parasitic capacitance Cdp of a specific level with a pixel electrode that it overlaps. For example, second data line DL2 may form parasitic capacitance with second pixel electrode P2 by overlapping second area a2 of second pixel electrode P2. Second data line DL2 may form parasitic capacitance with first pixel electrode P1 by overlapping third area a3 of first pixel electrode P1. From the perspective view of pixel electrodes, second area a2 of first pixel electrode P1 may overlap first data line DL1, and third area a3 of first pixel electrode P1 may overlap second data line DL2. First pixel electrode P1 may form parasitic capacitance with first data line DL1 through second area a2 and form parasitic capacitance with second data line DL2 through third area a3.
Second data line DL2 may be separated by a predetermined distance a from the boundary area between first pixel electrode P1 and second pixel electrode P2. The predetermined distance “a” may be a maximum error distance set in view of the possible misalignment of a data line. Even if second data line DL2 is misaligned, it may still form parasitic capacitance with second pixel electrode P2 by overlapping second area a2 of second pixel electrode P2 and may form parasitic capacitance with first pixel electrode P1 by overlapping third area a3 of first pixel electrode P1.
Referring to
Referring to
Parasitic capacitance formed by a pixel electrode and a data line according to one or more exemplary embodiments may have a constant value despite the misalignment of the data line. Accordingly, even if the 2-dot inversion method is used, there may be no substantial change in the parasitic capacitance in an inversion unit. This may prevent or reduce a horizontal line defect, thus providing a more improved display quality.
Referring to
Other components of LCD 20 are substantially identical to those of LCD 10 of
One or more exemplary embodiments may reduce or prevent a horizontal line defect caused by parasitic capacitance (Cdp), and may provide a more improved display quality.
Although certain exemplary embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Accordingly, the inventive concept is not limited to such embodiments, but rather to the broader scope of the presented claims and various obvious modifications and equivalent arrangements.
Number | Date | Country | Kind |
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10-2014-0163586 | Nov 2014 | KR | national |