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Multi-domain liquid crystal display and a thin film transistor substrate of the sameMulti-domain liquid crystal display and a thin film transistor substrate of the same description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20070182872, Multi-domain liquid crystal display and a thin film transistor substrate of the same. Brief Patent Description - Full Patent Description - Patent Application Claims
CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. application Ser. No. 10/509,207, filed on Sep. 24, 2004, which claims priority to Korean Patent Application No. 2002-19244 filed on Apr. 9, 2002, the disclosures of which are incorporated by reference herein in their entirety. BACKGROUND OF THE INVENTION [0002] (a) Field of the Invention [0003] The present invention relates to a liquid crystal display and in particular, vertically-aligned liquid crystal display having a pixel region including a plurality of domains for wide viewing angle. [0004] (b) Description of the Related Art [0005] A typical liquid crystal display (LCD) includes an upper panel provided with a common electrode and an array of color filters, a lower panel provided with a plurality of thin film transistors (TFTs) and a plurality of pixel electrodes, and a liquid crystal layer is interposed therebetween. The pixel electrodes and the common electrode are applied with electric voltages and the voltage difference therebetween causes electric field. The variation of the electric field changes the orientations of liquid crystal molecules in the liquid crystal layer and thus the transmittance of light passing through the liquid crystal layer. As a result, the LCD displays desired images by adjusting the voltage difference between the pixel electrodes and the common electrode. [0006] The LCD has a major disadvantage of its narrow viewing angle, and several techniques for increasing the viewing angle have been developed. Among these techniques, the provision of a plurality of cutouts or a plurality of projections on the pixel electrodes and the common electrode opposite each other along with the vertical alignment of the liquid crystal molecules with respect to the upper and the lower panels is promising. [0007] The cutouts provided both at the pixel electrodes and the common electrode give wide viewing angle by generating fringe field to adjust the tilt directions of the liquid crystal molecules. [0008] The provision of the projections both on the pixel electrode and the common electrode distorts the electric field to adjust the tilt directions of the liquid crystal molecules. [0009] The fringe field for adjusting the tilt directions of the liquid crystal molecules to form a plurality of domains is also obtained by providing the cutouts at the pixel electrodes on the lower panel and the projections on the common electrode on the upper panel. [0010] Among these techniques for widening the viewing angle, the provision of the cutouts has problems that an additional mask for patterning the common electrode is required, an overcoat is required for preventing the effect of the pigments of the color filters on the liquid crystal material, and severe disclination is generated near the edges of the patterned electrode. The provision of the projections also has a problem that the manufacturing method is complicated since it is required an additional process step for forming the projections or a modification of a process step. Moreover, the aperture ratio is reduced due to the projections and the cutouts. SUMMARY OF THE INVENTION [0011] It is a motivation of the present invention to provide a liquid crystal display manufactured by simple process and ensuring stable multi-domains. [0012] This and other motivations may be achieved by a liquid crystal display with a direction control electrode. A pixel electrode is capacitively coupled with the direction control electrode, and a switching thin film transistor is connected to the direction control electrode. [0013] A thin film transistor array panel is provided, which includes: an insulating substrate; a gate wire formed on the insulating substrate; a data wire formed on the insulating substrate and intersecting the gate wire in an insulating manner; a thin film transistor electrically connected to the gate wire and the data wire; a direction control electrode electrically connected to a terminal of the thin film transistor; and a pixel electrode electrically insulated from the direction control electrode and having a cutout proceeding along the direction control electrode, the pixel electrode being electrically floating. [0014] Preferably, the thin film transistor array panel further includes a storage electrode wire intersecting the data wire and forming a storage capacitor in association with the pixel electrode. [0015] Another thin film transistor array panel is provided, which includes: an insulating substrate; a gate wire formed on the insulating substrate and including a gate electrode and a gate line; a gate insulating layer formed on the gate wire; a semiconductor layer formed on the gate insulating layer; a data wire including a data line formed on the semiconductor layer and intersecting the gate line, a source electrode connected to the data line, and a drain electrode facing the source electrode; a direction control electrode connected to the drain electrode; a passivation layer formed on the data wire and the direction control electrode; and a pixel electrode formed on the passivation layer with an cutout and including a cutout overlap the direction control electrode at least in part. [0016] Preferably, the thin film transistor array panel further includes: a gate pad connected to one end of the gate line; a data pad connected to one end of the data line; a subsidiary gate pad formed on the passivation layer and connected to the gate pad through a contact hole; and a subsidiary data pad formed on the passivation layer and connected to the data pad through a contact hole. It is preferable that the cutout of the pixel electrode includes a plurality of X-shaped portions and a plurality of rectilinear portions, and the direction control electrode overlaps the X-shaped portions. The semiconductor layer may include a data-line semiconductor located under the data line, and a channel semiconductor located under the source and the drain electrodes, and the semiconductor layer may include a direction control electrode semiconductor located under the direction control electrode along the direction control electrode. The thin film transistor array panel further includes, preferably, a metallic piece formed of the same layer as the gate wire and placed under the direction control electrode along the direction control electrode. [0017] A liquid crystal display according to an embodiment of the present invention includes: a first insulating substrate; a gate wire formed on the first insulating substrate; a data wire formed on the first insulating substrate and intersecting the gate wire in an insulating manner to define a pixel area; a direction control electrode formed in the pixel area defined by the intersection of the gate wire and the data wire; a thin film transistor connected to the gate wire, the data wire, and the direction control electrode; an electrically floating pixel electrode formed in the pixel area, electrically insulated from the direction control electrode connected to the thin film transistor, and having a cutout proceeding along the direction control electrode; a second insulating substrate facing the first insulating substrate; a common electrode formed on the second insulating substrate; and a liquid crystal layer interposed between the first substrate and the second insulating substrate. [0018] The liquid crystal layer has negative dielectric anisotropy and liquid crystal molecules in the liquid crystal layer are aligned perpendicular to the first and the second substrates. Alternatively, the liquid crystal layer has positive dielectric anisotropy and liquid crystal molecules in the liquid crystal layer are aligned parallel to the first and the second substrates. The liquid crystal display may further include a storage electrode wire formed on the first substrate and forming a storage capacitor in association with the pixel electrode. The common electrode and the storage electrode wire are preferably supplied with the same voltage, and voltage difference between the pixel electrode and the common electrode V.sub.PC is given by:V.sub.PC=C.sub.DP.times.V.sub.DC/(C.sub.DP+C.sub.LC+C.sub.ST), where C.sub.DP indicates capacitance between the direction control electrode and the pixel electrode, C.sub.LC indicates capacitance between the pixel electrode and the common electrode, C.sub.ST indicates capacitance between the pixel electrode and the storage electrode, wire, and V.sub.DC is the voltage difference between the direction control electrode and the common electrode. BRIEF DESCRIPTION OF THE DRAWINGS [0019] FIG. 1 is an equivalent circuit diagram of an LCD according to an embodiment of the present invention; [0020] FIG. 2 shows waveforms of the voltage of a pixel electrode and the voltage of a DCE voltage for the capacitance between the pixel electrode and the DCE in an LCD according to an embodiment of the present invention. Continue reading about Multi-domain liquid crystal display and a thin film transistor substrate of the same... Full patent description for Multi-domain liquid crystal display and a thin film transistor substrate of the same Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Multi-domain liquid crystal display and a thin film transistor substrate of the same patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. 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