JP4500611B2 - Pixel structure of liquid crystal display - Google Patents

Description

  The present invention relates to a pixel structure of a liquid crystal display, and more particularly to a fast response pixel structure of a liquid crystal display.

  Twisted nematic (hereinafter simply referred to as TN) cells widely used in TFT color liquid crystal display devices (TFT / LCD (Thin Film Transistor / Liquid Crystal Display)) currently have a small viewing angle. As a result, contrast and image inversion are reduced when the LCD panel surface is viewed from an oblique direction. Various methods have been proposed to solve this problem, that is, to realize a wide viewing angle. Among such methods, there is an alignment division method in which each pixel of the LCD is divided into two parts and the two parts are oriented in different directions.

  However, these methods require complicated manufacturing processes. For example, in the case of the alignment dividing method, two rubbing steps are required. These steps further include the steps of coating, baking, patterning, and photoresist phenomenon and removal.

  In recent years, an OCB (Optically Compensated Bend) cell used as a liquid crystal cell instead of a TN cell has been studied. If the OCB cell technology is used, a wide viewing angle can be obtained more easily than the orientation division method, and a high-speed response characteristic that is one step faster than the conventional TN cell can be obtained.

  FIG. 1 is a perspective view showing the structure of an OCB cell. A liquid crystal material exhibiting a spray orientation 104 is encapsulated between two (upper and lower) glass substrates 100 and 102. Deflection plates 106 and 108 are arranged outside the two glass substrates 100 and 102, respectively. When a voltage is applied to the glass substrates 100 and 102, the liquid crystal material is changed from the splay alignment 104 to the bend alignment 110 as shown in FIG. 1B. In the bend alignment 110 cell, the upper and lower liquid crystal molecules are always symmetrically aligned, so the viewing angle dependence is contrasted around line AA '. An optical birefringence compensation (OCB) mode LCD obtains uniform viewing angle characteristics in all directions by correcting the birefringence of liquid crystal molecules.

  The OCB cell is in a splay alignment state when no bias voltage is applied, and exhibits a bend alignment state when a predetermined high voltage is applied. In order to allow the OCB cell to operate as a liquid crystal display device, the cell must be changed from a splay alignment to a bend alignment at startup. Since this process requires restart time, the response speed is reduced.

  FIG. 2A shows a plan view of the pixel structure of the thin film transistor LCD. A gate electrode 306 a of the switch transistor 306 is connected to the scanning line 302. The drain electrode 306 b of the switch transistor 306 is connected to the pixel electrode 308, and the source electrode 306 c is connected to the video data line 304. The common line 310 is used as a common electrode for the pixel electrode 308. The switch transistor 306 is usually a thin film transistor (TFT) disposed on a transparent substrate such as glass. By scanning the scanning line 302 and in response to the scanning signal, all the switch transistors 306 of the predetermined scanning line 302 are turned on. At the same time, a video signal is supplied to the video data line in synchronization with the selected scanning line 302.

  FIG. 2B is a cross-sectional view taken along line BB ′ of FIG. 2A. Liquid crystal material 326 is encapsulated between two (upper and lower) glass substrates 320 and 322. A conductor electrode 324 is disposed on the upper glass substrate 320. Referring to FIGS. 2A and 2B, normally, the liquid crystal molecules 328 on the pixel electrode 308 are in a splay state, and the liquid crystal molecules 326 on the other region are in a bend state. A high voltage is applied between the conductor electrode 324 and the pixel electrode 308 for a predetermined time when the liquid crystal display device using the OCB cell is started. At this time, the bend alignment liquid crystal molecules 326 change the alignment state of the liquid crystal molecules 328 on the pixel electrode 308 from the splay alignment to the bend alignment. However, some of the liquid crystal molecules 328 above the pixel electrode may fail to change and remain in bend alignment, which degrades the display quality of the LCD. Furthermore, the manufacturing costs increase due to the two orientation states required by this method. Furthermore, it is difficult to maintain a high tilt angle of the liquid crystal molecules in the bend alignment state. Accordingly, the liquid crystal display device can have a desired wide viewing angle characteristic, but the image quality required for the liquid crystal display device cannot be easily obtained. Furthermore, the above measures are not practical.

  FIG. 2C shows another alignment state according to the conventional method. The liquid crystal molecules 330 of all the pixels are in a splay state. According to this method, a high voltage is applied between the conductor electrode 324 and the pixel electrode 308 for a predetermined time when the liquid crystal display device using the OCB cell is activated, and the liquid crystal molecules 330 are changed from the splay state to the bend state. Can be changed. This fixed startup time usually takes tens of seconds or more. When the LCD is turned off, the liquid crystal molecules 330 return to the splay state. However, a high voltage is applied to a part of the liquid crystal molecules 330 such as the liquid crystal molecules between the video data line 304 and the pixel electrode 308 in this mode, so that when the LCD is turned on, two liquid crystal molecule states are present. There is something that is caused. Still another problem is that the OCB cell may return to the splay state during operation even when the liquid crystal molecules 330 are changed from the splay state to the bend state at the time of activation. The LCD must be restarted so that the display returns to normal.

  On the other hand, recent battery-powered systems such as notebook personal computers equipped with TFT color liquid crystal display devices are increasingly required to be power-saving. In order to save power, such a liquid crystal display device has a drive mode stop function for turning off the display. When the LCD is turned off, the OCB cell returns from bend alignment to splay alignment. Since a certain amount of time is required to recover the bend alignment state, the display cannot be turned on immediately.

  According to the above description, a liquid crystal display using a typical OCB cell needs to change the liquid crystal molecular alignment state from a splay alignment to a bend alignment during operation, which has two liquid crystal molecular alignment states. included. There are two typical methods of change. In one method, the liquid crystal molecules on the pixel electrode are first in a splay state, while the liquid crystal molecules on the other region are in a bend state. Then, a high voltage is applied between the conductor electrode and the pixel electrode, and the liquid crystal molecules on the pixel electrode are changed from the splay state to the bend state. However, this method requires two different orientation states, a splay state and a bend state, and the manufacturing cost increases. In another method, the liquid crystal molecules of all the pixels are in a splay state. An LCD employing this method is easy to manufacture, but this method requires a predetermined time when the liquid crystal display device is started in order to change the liquid crystal molecules from the spray state to the bend state. That is, this method does not provide an instantaneous response. In addition, some liquid crystal molecules do not accept high voltage, which affects display quality.

  Accordingly, a main object of the present invention is to provide a pixel structure that not only provides a wide viewing angle but also improves image quality.

  Another object of the present invention is to provide a pixel structure that uses only one alignment state in all cells and does not require a predetermined time when the liquid crystal display device is activated.

  Still another object of the present invention is to provide a driving method of a liquid crystal display device, which can change the OCB cell from a splay alignment to a bend alignment in a short time.

  It is a further object of the present invention to provide a liquid crystal display that can be manufactured by a simple and relatively inexpensive manufacturing method.

According to the present invention, there are a plurality of scan lines and a plurality of video data lines, and any adjacent scan line and any adjacent video data line define a pixel region, and each pixel region is a transistor. And a first substrate having a pixel electrode connected to the transistor, a plurality of common electrode lines disposed under the pixel electrode, a plurality of metal lines extending from the common electrode line, and the pixel electrode A plurality of holes penetrating and positioned above the metal line or the common electrode line, each of the pixel electrodes having at least one of the holes, each having a long axis; A second substrate separated from the substrate by a predetermined distance; a conductor electrode positioned on the second substrate and generating an electric field with the metal line; the conductor electrode; the pixel electrode; With the metal wire A liquid crystal molecule sandwiched between the conductor electrode and the metal line, wherein the liquid crystal molecule is bent from the splay alignment mode when a predetermined electric field is established between the conductor electrode and the metal line. The video data line, the common electrode line and the metal line are in the same layer, and the extending direction of the metal line located above the hole is parallel to the alignment direction of the liquid crystal molecules. A pixel structure of a liquid crystal display is provided.

  Meanwhile, the present invention also provides a driving circuit for driving the metal electrode. The drive circuit includes an inverter that inverts the field frame input to the source / drain electrodes of the transistor. An inverted field frame is used to control the common electrode. On the other hand, this transistor is controlled by a scanning signal. Therefore, the operation of this transistor is synchronized with the operation of the switch transistor. That is, when a voltage is sequentially applied to the metal electrode and the pixel electrode, the control circuit first turns on the transistor and then inverts the field frame.

  According to the present invention, the metal electrode can be disposed at the center of the pixel electrode or around the pixel electrode. Since the present invention does not require two alignment states in the liquid crystal cell, a complicated manufacturing process can be avoided. Furthermore, a predetermined time for changing the liquid crystal molecules from the splay state to the bend state when the LCD is activated is not required. Therefore, the LCD using the pixel structure of the present invention exhibits not only high speed response but also high display quality.

  Many of the above-described aspects and attendant advantages of the present invention can be more readily understood by reference to the following detailed description in conjunction with the accompanying drawings.

  Without limiting the spirit and scope of the present invention, the circuit structure proposed in the present invention will be described in one preferred embodiment. Those skilled in the art can recognize the embodiment and apply the pixel electrode structure using the OCB mode and the operation method of the present invention to various liquid crystal displays. According to this pixel structure, since the pixel region does not require two alignment states in the liquid crystal cell, a complicated manufacturing process can be avoided. Furthermore, the present invention does not require a predetermined time for changing the liquid crystal molecules from the splay state to the bend state when the LCD is activated. Therefore, the LCD using the pixel structure of the present invention has high display quality as well as high speed response. The application of the present invention is not limited to the preferred embodiments described below.

  According to the present invention, the metal electrode is formed in the pixel region. The metal electrode is controlled by a common electrode. Liquid crystal molecules in all pixel regions are in a splayed state. A voltage is applied to the metal electrode to change the liquid crystal molecules on the metal electrode from a splay state to a bend state during operation. Thereafter, a voltage is applied to the pixel electrode. At this time, the liquid crystal molecules in the bend state change the liquid crystal molecules on the pixel electrode from the splay state to the bend state. Accordingly, the liquid crystal molecules in the entire pixel region show a bend state.

(First embodiment)
FIG. 3A shows a plan view of a pixel region according to the first embodiment of the present invention. A silicon island 506 a of the switch transistor 506 is connected to the scanning line 502. When the switch transistor 506 is selected, a scanning signal is transmitted through the scanning line 502 to turn on the switch transistor 506. The video signal on the video data line 504 is transferred to the pixel electrode 508 through the switch transistor 506. A drain electrode 506 b of the switch transistor 506 is connected to the pixel electrode 508. A source electrode 506 c of the switch transistor 506 is connected to the video data line 504. The common electrode line 510 is used as a common electrode for the pixel electrode 508. An S-shaped metal electrode 512 is formed around the pixel region. The metal electrode 512 is controlled by the common electrode line 510.

  In general, the source electrode 506 c and the drain electrode 506 b of the switch transistor 506 can receive video data from the video data line 504. Accordingly, by scanning the scanning line 502 and in accordance with the scanning signal, the switch transistor 506 of the predetermined scanning line 502 is turned on. At the same time, the video signal on the video data line 504 is transferred to the pixel electrode 508 through the switch transistor 506, and the image is shown on the liquid crystal display.

  FIG. 3B shows a cross-sectional view along line AA 'in FIG. 3A, with all liquid crystal molecules in the splayed state. The lower substrate 514 and the upper substrate 516 are separated from each other by a predetermined distance. . The lower substrate 514 and the upper substrate 516 are preferably made of a transparent insulator. A liquid crystal layer 518 having a plurality of liquid crystal molecules is sandwiched between a lower substrate 514 and an upper substrate 516, and the plurality of liquid crystal molecules are in a splay state. The video data line 504 and the metal line 512 are sequentially formed on the lower substrate 514. An isolation layer 530 is disposed between the video data line 504 and the metal line 512. The pixel electrode 508 is formed on the inner surface of the lower substrate 514. Another isolation layer 532 is disposed between the video data line 504 and the pixel electrode 508. A conductor electrode 520 is formed on the inner surface of the upper substrate 516. Both the pixel electrode 508 and the conductor electrode 520 are formed of a transparent conductor, preferably an ITO material, for example. Further, an alignment layer (not shown) is formed on the inner surface of the lower substrate 514 where the pixel electrode 508 is disposed and on the inner surface of the upper substrate 516 where the conductor electrode 520 is disposed. Here, the alignment layer has a preliminary tilt angle of approximately 5 degrees in the splayed state.

  A voltage is applied to the metal electrode 512 to change the liquid crystal molecules on the metal electrode 512 from the splay state to the bend state during operation as shown in FIG. 3C. FIG. 3C shows a cross-sectional view along the line AA ′ of FIG. 3A, in which some of the liquid crystal molecules are changed to a bend state. According to the first embodiment, a voltage is applied between the common electrode 510 and the conductor electrode 520 disposed on the upper substrate 516. Accordingly, there is also a voltage difference between the metal wire 512 controlled by the common electrode 510 and the conductor electrode 520. As a result, the liquid crystal molecules between the metal electrode and the upper substrate 516 are changed from the splay state to the bend state due to the voltage difference.

Still referring to FIG. The pixel electrode 508 is divided into two parts 508a and 508b. The liquid crystal molecules 518a in the bend state are divided into two parts 508a and 508b. The liquid crystal molecules 518a have a separating function. The voltage difference between the metal line 512 and the conductor electrode 520 still exists after the voltage difference between the pixel electrode and the conductor electrode 520 occurs. That is, the liquid crystal molecules 518a reliably remain in the bend state due to the voltage difference that still exists. Accordingly, the liquid crystal molecules 518a isolate the influence from the outside of the pixel electrode in which the liquid crystal molecules are in the splay state. When the liquid crystal display is turned off, the voltage applied to the common electrode 510 is removed. At this time, the liquid crystal molecules between the conductor electrode 520 and the metal electrode 512 are changed from the bend state to the splay state.

Still referring to FIG. 3A again. During operation, the liquid crystal molecules between the conductor electrode 520 and the metal electrode 512 are first changed from the original splay state to the bend state, and then a voltage is applied to the pixel electrode 508. Next, by scanning the scanning line 502 and in accordance with the scanning signal, the switch transistor 506 of the predetermined scanning line 502 is turned on. At the same time, the video signal on the video data line 504 is transferred to the pixel electrode 508 through the switch transistor 506. That is, a voltage difference is generated between the pixel electrode 508 and the conductor electrode 520 of the upper substrate 516. At this time, the liquid crystal molecules in the pixel region are changed from the splay state to the bend state. Accordingly, the liquid crystal molecules in the entire liquid crystal region are in a bend state. On the other hand, a part of the metal electrode 512 may overlap with the pixel electrode 508. In that case, the overlapping portion functions as a capacitor to increase the response speed of the pixel electrode.

(Second embodiment)
FIG. 4A shows a plan view of a pixel region according to a second embodiment of the present invention. A silicon island 706 a of the switch transistor 706 is connected to the scanning line 702. When the switch transistor 706 is selected, the switch transistor 706 is turned on by the scanning signal of the scanning line 702. The video signal on the video data line 704 is transferred to the pixel electrode 708 through the switch transistor 706. A drain electrode 706 b of the switch transistor 706 is connected to the pixel electrode 708. A source electrode 706 c of the switch transistor 706 is connected to the video data line 704. The common electrode line 710 is used as a common electrode for the pixel electrode 708. A metal electrode 712 is formed around the pixel region. The metal electrode 712 is controlled by a common electrode line 710.

  FIG. 4B shows a cross-sectional view along line AA 'of FIG. 4A. The lower substrate 714 and the upper substrate 716 are opposed to each other with a predetermined distance therebetween. . The lower substrate 714 and the upper substrate 716 are preferably made of a transparent insulator. A liquid crystal layer 718 having a plurality of liquid crystal molecules is sandwiched between a lower substrate 714 and an upper substrate 716, and the plurality of liquid crystal molecules are in a splay state. Video data lines 704 and metal lines 712 are sequentially formed on the lower substrate 714. An isolation layer 730 is disposed between the video data line 704 and the metal line 712. The pixel electrode 708 is formed on the inner surface of the lower substrate 714. Another isolation layer 732 is disposed between the video data line 704 and the pixel electrode 708. A conductor electrode 720 is formed on the inner surface of the upper substrate 716. Both the pixel electrode 708 and the conductor electrode 720 are formed of a transparent conductor, preferably an ITO material, for example. Further, an alignment layer (not shown) is formed on the inner surface of the lower substrate 714 on which the pixel electrode 708 is disposed and on the inner surface of the upper substrate 716 on which the conductor electrode 720 is disposed. Here, the alignment layer has a preliminary tilt angle of approximately 5 degrees in the splay state.

  A voltage is applied to the metal electrode 712 to change the liquid crystal molecules 718a on the metal electrode 712 from a splay state to a bend state during operation as shown in FIG. 4C. FIG. 4C shows a cross-sectional view along line AA ′ of FIG. 4A according to the second embodiment, in which some of the liquid crystal molecules are changed to a bend state. According to the second embodiment, a voltage is applied between the common electrode 710 and the conductor electrode 720 disposed on the upper substrate 716. Accordingly, there is also a voltage difference between the metal electrode 712 controlled by the common electrode 710 and the conductor electrode 720. As a result, the liquid crystal molecules between the metal electrode 712 and the upper substrate 716 are changed from the splay state to the bend state due to the voltage difference as shown in FIG. 4C.

  Referring to FIG. 4C again, the pixel electrode 708 is isolated using the liquid crystal molecules 718a in the bend state. The voltage difference between the metal electrode 712 and the conductor electrode 720 still exists after the voltage difference between the pixel electrode 708 and the conductor electrode 720 occurs. In other words, the liquid crystal molecules 718a are reliably maintained in the bend state by the voltage difference that still exists. Accordingly, the liquid crystal molecules 718a isolate the pixel electrode 708 from the influence outside the pixel electrode 708 in which the liquid crystal molecule is in the splayed state. When the liquid crystal display is turned off, the voltage applied to the common electrode 710 is removed. At this time, the liquid crystal molecules between the common electrode 710 and the metal electrode 712 can be changed from the bend state to the splay state.

  During operation, the liquid crystal molecules between the common electrode 710 and the metal electrode 712 are first changed from the original splay state to the bend state, and then a voltage is applied to the pixel electrode 708. Next, the scanning transistor 706 of the predetermined scanning line 702 is turned on by scanning the scanning line 702 and according to the scanning signal. At the same time, the video signal on the video data line 704 is transferred to the pixel electrode 708 through the switch transistor 706. That is, a voltage difference is generated between the pixel electrode 708 and the conductor electrode 720 of the upper substrate 716. At this time, the liquid crystal molecules in the pixel region can be changed from the splay state to the bend state. Accordingly, the liquid crystal molecules in the entire liquid crystal region are in a bend state. On the other hand, a part of the metal electrode 712 may overlap with the pixel electrode 708. The overlapping portion functions as a capacitor to increase the response speed of the pixel electrode.

(Third embodiment)
FIG. 5A shows a plan view of a pixel region according to a third embodiment of the present invention. A silicon island 806 a of the switch transistor 806 is connected to the scanning line 802. A drain electrode 806 b of the switch transistor 806 is connected to the pixel electrode 808. A source electrode 806 c of the switch transistor 806 is connected to the video data line 804. The common electrode line 810 is used as a common electrode for the pixel electrode 808. According to the third embodiment, the metal electrode 812 and the common electrode 810 are H-shaped. The metal electrode 812 is controlled by a common electrode line 810.

  FIG. 5B shows a cross-sectional view along line AA 'of FIG. 5A. The lower substrate 814 and the upper substrate 816 are separated from each other by a predetermined distance. The lower substrate 814 and the upper substrate 816 are preferably made of a transparent insulator. A liquid crystal layer 818 having a plurality of liquid crystal molecules is sandwiched between a lower substrate 814 and an upper substrate 816, and the plurality of liquid crystal molecules are in a splay state. Video data lines 804 and metal lines 812 are sequentially formed on the lower substrate 814. An isolation layer 830 is disposed between the video data line 804 and the metal line 812. The pixel electrode 808 is formed on the inner surface of the lower substrate 814. Another isolation layer 832 is disposed between the video data line 804 and the pixel electrode 808. A conductor electrode 820 is formed on the inner surface of the upper substrate 816. Both the pixel electrode 808 and the conductor electrode 820 are formed of a transparent conductor, preferably an ITO material, for example. Further, an alignment layer (not shown) is formed on the inner surface of the lower substrate 814 on which the pixel electrode 31 is disposed and on the inner surface of the upper substrate 816 on which the conductor electrode 820 is disposed. Here, the alignment layer has a preliminary tilt angle of approximately 5 degrees in the splay state. In operation, a voltage is applied to the metal electrode 812 to cause the liquid crystal molecules 818a on the metal electrode 812 to change from the splayed state to the bend state as shown in FIG. 5C.

  Referring to FIG. 5C again, the pixel electrode 808 is isolated using liquid crystal molecules 818a in a bend state. That is, the voltage difference between the metal electrode 812 and the conductor electrode 820 still exists after the voltage difference between the pixel electrode 808 and the conductor electrode 820 occurs. In other words, the liquid crystal molecules 818a are reliably maintained in the bend state by the voltage difference that still exists. Accordingly, the liquid crystal molecules 818a isolate the pixel electrode 808 from the influence from the outside of the pixel electrode 808 in which the liquid crystal molecule is in the splay state. When the liquid crystal display is turned off, the voltage applied to the common electrode 810 is removed. At this time, the liquid crystal molecules between the common electrode 810 and the metal electrode 812 are changed from the bend state to the splay state.

  During operation, the liquid crystal molecules between the common electrode 810 and the metal electrode 812 are first changed from the original splay state to the bend state, and then a voltage is applied to the pixel electrode 808. Next, the scanning transistor 806 of the predetermined scanning line 802 is turned on by scanning the scanning line 802 and according to the scanning signal. At the same time, the video signal on the video data line 804 is transferred to the pixel electrode 808 through the switch transistor 806. That is, a voltage difference is generated between the pixel electrode 808 and the conductor electrode 820 of the upper substrate 816. At this time, the liquid crystal molecules in the pixel region can be changed from the splay state to the bend state. Accordingly, the liquid crystal molecules in the entire liquid crystal region are in a bend state. On the other hand, a part of the metal electrode 812 may overlap with the pixel electrode 808. The overlapping portion functions as a capacitor, and the response speed of the pixel electrode can be increased.

(Fourth embodiment)
Referring to FIG. 6A, a plan view of a pixel region according to a fourth embodiment of the present invention is shown. A silicon island 906 a of the switch transistor 906 is connected to the scanning line 902. A drain electrode 906 b of the switch transistor 906 is connected to the pixel electrode 908. A source electrode 906 c of the switch transistor 906 is connected to the video data line 904. The common electrode line 910 is used as a common electrode for the pixel electrode 909. According to the fourth embodiment, the metal electrode 912 and the common electrode 910 have a cross shape. The metal electrode 912 is controlled by the common electrode line 910.

  FIG. 6B shows a cross-sectional view along line AA 'of FIG. 5A. The lower substrate 914 and the upper substrate 916 are opposed to each other with a predetermined distance therebetween. The lower substrate 914 and the upper substrate 916 are preferably formed of a transparent insulator. A liquid crystal layer 918 having a plurality of liquid crystal molecules is sandwiched between a lower substrate 914 and an upper substrate 916, and the plurality of liquid crystal molecules are in a splay state. Video data lines 904 and metal lines 912 are sequentially formed on the lower substrate 914. The isolation layer 930 is disposed between the video data line 904 and the metal line 912. The pixel electrode 908 is formed on the inner surface of the lower substrate 914. Another isolation layer 932 is disposed between the video data line 904 and the pixel electrode 908. The conductor electrode 920 is formed on the inner surface of the upper substrate 916. Both the pixel electrode 908 and the conductor electrode 920 are formed of a transparent conductor, preferably an ITO material, for example. Furthermore, an alignment layer (not shown) is formed on the inner surface of the lower substrate 914 on which the pixel electrode 31 is disposed and on the inner surface of the upper substrate 916 on which the conductor electrode 920 is disposed. Here, the alignment layer has a preliminary tilt angle of approximately 5 degrees in the splay state.

Referring to FIG. 6c again, the pixel electrode 908 is formed using liquid crystal molecules 918a in a bend state.
Isolate. That is, the voltage difference between the metal electrode 912 and the conductor electrode 920 is the pixel electrode 908.
And the conductor electrode 920 still exist after the voltage difference has occurred. The voltage difference still exists ensures that the liquid crystal molecules 918a are maintained in a bend state. Accordingly, the liquid crystal molecules 918a isolate the pixel electrode 908 from the influence outside the pixel electrode 908 in which the liquid crystal molecules are in the splay state. When the liquid crystal display is turned off, the voltage applied to the common electrode 910 is removed. At this time, the liquid crystal molecules between the conductor electrode 920 and the metal electrode 912 are converted from the bend state to the splay state.

  During operation, the liquid crystal molecules between the common electrode 910 and the metal electrode 912 are first changed from the original splay state to the bend state, and then a voltage is applied to the pixel electrode 909. Next, the scanning transistor 906 of the predetermined scanning line 902 is turned on by scanning the scanning line 902 and according to the scanning signal. At the same time, the video signal on the video data line 904 is transferred to the pixel electrode 908 through the switch transistor 906. That is, a voltage difference is generated between the pixel electrode 908 and the conductor electrode 920 of the upper substrate 916. At this time, the liquid crystal molecules in the pixel region are changed from the splay state to the bend state. Accordingly, the liquid crystal molecules in the entire liquid crystal region are in a bend state. On the other hand, a part of the metal electrode 912 overlaps with the pixel electrode 908. The overlapping portion functions as a capacitor, and the response speed of the pixel electrode can be increased.

  In the four embodiments described above, the metal electrode line connected to the common electrode line and the video data line are arranged in different layers. However, in other embodiments, the metal electrode line connected to the common electrode line and the video data line may be disposed on the same layer. For example, as shown in FIGS. 7A and 7B of the first embodiment, the metal electrode line and the video data line connected to the common electrode line may be arranged in the same layer.

  As shown in FIG. 7A, the silicon island 506 a of the switch transistor 506 is connected to the scanning line 502. When the switch transistor 506 is selected, a scanning signal is transmitted via the scanning line 502, and the switch transistor 506 is turned on. A video signal on the video data line 504 is transmitted to the pixel electrode 508 through the switch transistor 506. A drain electrode 506 b of the switch transistor 506 is connected to the pixel electrode 508. A source electrode 506 c of the switch transistor 506 is connected to the video data line 504. The common electrode line 510 is used as a common electrode for the pixel electrode 508. The common electrode line 510 is arranged in parallel with the video data line 504. The S-shaped metal electrode 512 is disposed around the pixel region. The metal electrode 512 is controlled by the common electrode line 510. The metal electrode line connected to the common electrode line and the video data line are disposed on the same layer.

  FIG. 7B is a cross-sectional view taken along line AA 'in FIG. 7A, in which all liquid crystal molecules are in a splayed state. The lower substrate 514 and the upper substrate 516 face each other with a predetermined distance. The lower substrate 514 and the upper substrate 516 are preferably formed of a transparent insulator. A liquid crystal layer 518 having a plurality of liquid crystal molecules is sandwiched between a lower substrate 514 and an upper substrate 516, and the plurality of liquid crystal molecules are in a splay state. The video data line 504 and the metal line 512 are formed apart from each other on the same layer on the lower substrate 514. The pixel electrode 508 is formed on the inner side surface of the lower substrate 514. Another isolation layer 532 is disposed between the video data line 504, the metal line 512, and the pixel electrode 508. The conductor electrode 520 is formed on the inner surface of the upper substrate 516. Both the pixel electrode 508 and the conductor electrode 520 are formed of a transparent conductor, preferably, for example, ITO or IZO material.

  The structure in which the metal line connected to the common electrode line and the video data line are arranged on the same layer may be applied to the above-described four embodiments.

  As described above, an additional metal electrode is formed in the pixel region. The metal electrode is controlled by a common electrode. Liquid crystal molecules in all pixel regions are in a splayed state. During operation, a voltage is applied to the metal electrode to change the liquid crystal molecules on the metal electrode from the splayed state to the bend state. Thereafter, a voltage is applied to the pixel electrode so that the entire pixel region shows a bend state.

  The metal electrode can be disposed at the center of the pixel electrode or around the pixel electrode. The metal electrode and the common electrode can be cross-shaped or H-shaped. Since the present invention does not require two alignment states in the liquid crystal cell, a complicated manufacturing process is avoided according to the present invention. Furthermore, a predetermined time for changing the liquid crystal molecules from the splay state to the bend state when the LCD is activated is not required. Therefore, the LCD using the pixel structure of the present invention has high display quality as well as high speed response.

  Meanwhile, the present invention also provides a driving circuit for driving the metal electrode. FIG. 8A shows a waveform from negative to positive drive timing according to the first embodiment. This waveform can be used in the four embodiments described above. 3A to 3C and FIG. 8A, the voltage signal 404 is first applied to the common electrode 510. Therefore, the voltage signal 404 is also applied to the metal electrode 512 controlled by the common electrode. At this time, the liquid crystal molecules arranged on the metal electrode 512 are changed from the splay state to the bend state. On the other hand, a part of the metal electrode 512 overlaps with the pixel electrodes 508a and 508b, and a voltage exists in the metal electrode 512 as shown in FIGS. 3B and 3C. The metal electrodes and pixel electrodes 508a and 508b are all conductors. Accordingly, the overlapping portions 524 and 526 can function as capacitors. That is, this voltage applied to the metal electrode 512 charges the overlapping portions 524 and 526 to increase the potential of the pixel electrode.

At time T ₁ , the scanning transistor 502 is scanned, and the switch transistor 506 of the predetermined scanning line 502 is turned on in response to the scanning signal 402. At the same time, the pixel potential 406 of the video data line 504 is transferred to the pixel electrode 508 through the switch transistor 506. That is, a voltage difference is generated between the pixel electrode 508 and the conductor electrode 520 of the upper substrate 516 to change the liquid crystal molecules from the splay state to the bend state. Note that the overlapping portions 524 and 526 function as capacitors, and thus the pixel electrode 508 has an initial potential. That is, it becomes easier to generate a voltage at the pixel electrode 508 that changes the liquid crystal molecules from the splay state to the bend state. Therefore, the response speed can be increased.

FIG. 8B shows a waveform from positive to negative drive timing. This waveform can be used in the four embodiments described above. 3A to 3C and FIG. 8B, the voltage signal 408 applied to the common electrode 510 is first switched from a high voltage to a low voltage. Therefore, the metal electrode 512 controlled by the common electrode is also in a low voltage state. On the other hand, as shown in FIGS. 3B and 3C, a part of the metal electrode 512 overlaps the pixel electrodes 508a and 508b. The metal electrodes and pixel electrodes 508a and 508b are all conductors. Accordingly, the overlapping portions 524 and 526 function as capacitors. Thus, the metal electrode 512 when in a low potential state, is reduced to a specific value in the pixel electrode 508a and 508b of the potential 410 and time _{T 2.} However, at this time, since the scanning signal 412 does not select the switch transistor 506, the switch transistor 506 is still turned off. That is, the potential 410 of the pixel electrodes 508a and 508b is maintained at a constant value. At time _{T 3,} when the scanning signal 412 of the scanning line 502 selects the switch transistor 506, the switch transistor 506 is turned on. The potentials of the pixel electrodes 508a and 508b are discharged through the switch transistor 506 to lower the potential 410.

9A and 9B show waveforms according to the second embodiment, and FIG. 9B shows a waveform from positive to negative drive timing. This waveform can be used in the four embodiments described above. According to FIGS. 3A to 3C and FIG. 9A, the switch transistor 506 of the predetermined scan line 502 is turned on by scanning the scan line 502 and in response to the scan signal 602. At the same time, the pixel potential 606 of the video data line 504 is transferred to the pixel electrode 508 through the switch transistor 506. Next, at time T _1, the voltage signal 604 is switched from the low potential to the high potential. That is, the common electrode also has a high potential. Therefore, the metal electrode 512 controlled by the common electrode 510 also has a high potential that changes the liquid crystal molecules from the splay state to the bend state.

  On the other hand, a part of the metal electrode 512 overlaps with the pixel electrodes 508a and 508b, and a voltage exists in the metal electrode 512 as shown in FIGS. 3B and 3C. The metal electrodes and pixel electrodes 508a and 508b are all conductors. Accordingly, the overlapping portions 524 and 526 function as capacitors. That is, this voltage applied to the metal electrode 512 charges these overlapping portions 524 and 526 and raises the potential 606 of the pixel electrode. It becomes easier to generate a voltage at the pixel electrode 508 that changes the liquid crystal molecules from the splay state to the bend state.

FIG. 9B shows a waveform from positive to negative drive timing according to the second embodiment. This waveform may be used in the four embodiments described above. According to FIGS. 3A to 3C and FIG. 9B, by scanning the scanning line 502 and in response to the scanning signal 612, the switch transistor 506 of the predetermined scanning line 502 is turned on to lower the pixel potential 610. On the other hand, as shown in FIGS. 3B and 3C, a part of the metal electrode 512 overlaps the pixel electrodes 508a and 508b. Overlapping portions 524 and 526 function as capacitors. This capacitor function maintains the pixel potential of the pixel electrode 508 at a constant value. At time T _2, the voltage signal 608 of the common electrode 510 is varied from a high potential to the low potential. The metal electrode 512 controlled by the common electrode 510 is also at a low potential, whereby electric charges stored in the overlapping portions 524 and 526 are discharged, and the pixel potential 610 of the pixel electrode 508 is lowered.

10A and 10B show waveforms according to the third embodiment, and FIG. 10A shows a waveform from positive to negative drive timing. This waveform can be used in the four embodiments described above. According to FIGS. 3A to 3C and FIG. 9A, the switch transistor 506 of a given scan line 502 is turned on at time T ₁ by scanning the scan line 502 and in response to the scan signal 202. Next, the pixel potential 206 of the video data line 504 is transferred to the pixel electrode 508 through the switch transistor 506. At the same time, the voltage signal 204 is switched from a low potential to a high potential. That is, the common electrode also has a high potential. Therefore, the metal electrode 512 controlled by the common electrode 510 also has a high potential that changes the liquid crystal molecules from the splay state to the bend state.

  On the other hand, as shown in FIGS. 3B and 3C, part of the metal electrode 512 overlaps the pixel electrodes 508a and 508b. The metal electrode and the pixel electrodes 508a and 508b are all conductors. Overlapping portions 524 and 526 function as capacitors. Therefore, this voltage applied to the metal electrode 512 charges these overlapping portions 524 and 526 and raises the potential 206 of the pixel electrode. It becomes easier to generate a voltage at the pixel electrode 508 that changes the liquid crystal molecules from the splay state to the bend state.

FIG. 10B shows a waveform from positive to negative drive timing according to the third embodiment. This waveform can be used in the four pixel structure embodiment described above. According to FIGS. 3A to 3C and 8B, by scanning the scanning lines 502, and in accordance with the scanning signal 212, switching transistors 506 of a given scan line 502 pixel potential 210 at the time set to the ON _{T 2} Reduce. At the same time, the voltage signal 208 of the common electrode 510 is changed from a high potential to a low potential. The metal electrode 512 controlled by the common electrode 510 also has a low potential. On the other hand, as shown in FIGS. 3B and 3C, part of the metal electrode 512 overlaps the pixel electrodes 508a and 508b. Overlapping portions 524 and 526 function as capacitors. Since the potential of the common electrode 510 is low, the charges stored in the overlapping portions 524 and 526 are discharged, and the pixel potential 210 of the pixel electrode 508 is lowered.

  According to the pixel structure of the present invention, a part of the metal electrode overlaps with the pixel electrode to function as a capacitor, thereby increasing the response speed.

  FIG. 11 is a plan view in which the pixel electrode structure of the present invention is used in a TFT-LCD, and the four pixel structures described above may be used in this embodiment. The gate electrodes of the switch transistors 14, 16, 18 and 19 are connected to the scanning lines 82, 84, 86 and 88, respectively. The drain electrodes of the switch transistors 14, 16, 18 and 19 are connected to the pixel electrodes 24, 26, 28 and 19, respectively, and the source electrodes are connected to the video data line 72, respectively. Common lines 90, 92, 94, and 96 are used as common electrodes for pixel electrodes 24, 26, 28, and 19, respectively, to control metal electrodes (not shown). When the switch transistor 14 is selected by a predetermined scanning line, the video signal supplied to the video data line 72 is transferred to the pixel electrode 24 through the switch transistor 14 and an image is shown on the display.

  FIG. 12A shows a schematic diagram of a drive circuit that generates a waveform as shown in FIGS. 8A and 8B applied to a pixel structure as shown in FIG. Note that FIG. 12A shows only a common electrode for driving two different pixel electrodes. However, this drive circuit may be extended to drive all pixel structures. The driving method is the same as that described below.

Referring to FIGS. 11 and 12A, the drive circuit of the present invention, by using a voltage signal at the output terminal V _com1 common electrode 92 is driven, the common electrode 94 is driven using a voltage signal at the output terminal V _com2 Is done. The switch of the transistor 30 is controlled by the scanning line 82, and the switch of the transistor 32 is controlled by the scanning line 84. An inverter 34 is disposed between the transistor 30 and the output terminal _Vcom1 to change an input signal from the transistor 30. Other inverter 36, the transistor 32 and is arranged to change the signal at the output terminal _{V com1} between the output terminal _{V com2.}

In operation, a frame signal V _in consisting of two fields 38 and 40 is input from transistor 30. The time for each field is 1/60 second. When transistor 30 is turned on by scan line 82, first field signal 38 is transferred through transistor 30 to inverter 34. The inverter 34 inverts the first field signal 38 and transmits the inverted first field signal 38 from the output terminal _Vcom1 to drive the common electrode 92. Next, the transistor 32 is turned on and inverted by the scanning line 84, and the first field signal 38 is transferred to the inverter 36 through the transistor 32. The inverter 36 inverts the received signal again and transmits it from the output terminal _Vcom2 to drive the common electrode 94.

Accordingly, after the common electrode 92 is driven by the driving signal from the output terminal _Vcom1 by the waveform generated by the driving circuit of the present invention, the switch transistor 16 of the pixel electrode 26 is turned on by the scanning signal of the scanning line 84. The Therefore, the waveform shown in FIG. 7A is formed. Among these, the waveform 404 is a signal of the output terminal _Vcom1 , and the waveform 402 is a signal of the scanning line 84.

Next, when the transistor 30 receives the signal of the scanning line 82 again, the second field signal 40 is transferred to the inverter 34 through the transistor 30. The inverter 34 may invert the second field signal and transmit the inverted second field signal from the output terminal _Vcom1 to drive the common electrode 92. Next, when the transistor 32 is turned on by the scanning line 84, the inverted second field signal 40 is transferred to the inverter 36 through the transistor 32. The inverter 36 inverts the received signal again and transmits it from the output terminal _Vcom2 to drive the common electrode 94.

Therefore, after the common electrode 92 receives a signal from the output terminal _Vcom1 , the switch transistor 16 of the pixel electrode 26 is turned on by the scanning signal of the scanning line 84. In this way, the waveform shown in FIG. 8B is formed, of which the waveform 408 is the signal of the output terminal _Vcom1 , and the waveform 412 is the signal of the scanning line 84.

FIG. 12B shows a detailed view of the drive circuit of FIG. 12A that generates the drive voltage. The operation method of the inverter will be described below. When transistor 30 is turned on by a signal on scan line 82, first field signal 38 is transferred through transistor 30 to the gate electrodes of transistors 42 and 44. Transistors 42 and 44 are still off because first field signal 38 is at a low potential. Since the drain electrode and the source electrode are connected to each other, the transistor is turned on. The transistor is also turned on by a high voltage through transistor 46. Therefore, the signal at the output terminal _Vcom1 is a high voltage signal.

Similarly, when the transistor 30 is turned on again by the signal of the scanning line 82, the second field signal 40 is transferred through the transistor 30 to the gate electrodes of the transistors 42 and 44. Since the second field signal 40 is at a high potential, the transistors 42 and 44 are turned on. The gate electrode of the transistor 48 is connected to a low potential through the transistor 42. Accordingly, transistor 48 is turned off. Therefore, the output terminal _Vcom1 is connected to the low voltage signal through the transistor 44.

The drive circuit shown in FIG. 12A can be used to generate waveforms as shown in FIGS. 9A and 9B. With both reference to FIGS. 11 and 12A, the common electrode 92 is driven using a voltage signal at the output terminal _{V com1,} common electrode 94 is driven using a voltage signal at the output terminal _{V com2.} However, the switch of transistor 30 is controlled by scan line 86 and the switch of transistor 32 is controlled by scan line 88. An inverter 34 is disposed between the transistor 30 and the output terminal _Vcom1, and inverts an input signal from the transistor 30. Other inverter 36 inverts the arrangement has been input signal at the output terminal _{V com1} between the transistor 32 and the output terminal _{V com2.}

In operation, a frame signal V _in consisting of two fields 38 and 40 is input from transistor 30. Here, the time of each field is 1/60 second. When the transistor 30 is turned on by the scanning signal of the scanning line 86, the first field signal 38 is transferred to the inverter 34 through the transistor 30. The inverter 34 inverts the first field signal 38 and transmits the inverted first field signal 38 from the output terminal _Vcom1 to drive the common electrode 92. Next, when the transistor 32 is turned on by the scanning line 88, the inverted first field signal 38 is transferred to the inverter 36 through the transistor 32. The inverter 36 inverts the received signal again and transmits it from the output terminal _Vcom2 to drive the common electrode 94.

Therefore, according to the waveform generated by the driving circuit of the present invention, after the switch transistor 18 of the pixel electrode 28 is turned on by the scanning signal of the scanning line 86, the common electrode 92 is driven by the driving signal from the output terminal _Vcom1 . Driven. Therefore, the waveform shown in FIG. 8A is formed, among which the waveform 604 is the signal of the output terminal _Vcom2 , and the waveform 602 is the signal of the scanning line 86.

Next, when the transistor 30 receives the signal of the scanning line 86 again, the second field signal 40 is transferred to the inverter 34 through the transistor 30. The inverter 34 inverts the second field signal 40 and transmits the inverted second field signal 40 from the output terminal _Vcom1 to drive the common electrode 92. Next, when the transistor 32 is turned on by the scanning line 88, the inverted second field signal 40 is transferred to the inverter 36 through the transistor 32. The inverter 36 inverts the received signal again and transmits it from the output terminal _Vcom2 to drive the common electrode 94.

Accordingly, after the switch transistor 18 of the pixel electrode 28 is turned on by the scanning signal of the scanning line 86, the common electrode 94 receives a signal from the output terminal _Vcom2 . In this way, the waveform shown in FIG. 8B is formed, among which the waveform 608 is the signal of the output terminal _Vcom2 , and the waveform 612 is the signal of the scanning line 86.

The drive circuit shown in FIG. 12A can be used to generate waveforms as shown in FIGS. 10A and 10B. With both referring to FIG. 11 and FIG. 12A, the common electrode 92 is driven using a voltage signal at the output terminal _{V com1,} common electrode 94 is driven using a voltage signal at the output terminal _{V com2.} However, the switch of transistor 30 is controlled by scan line 84 and the switch of transistor 32 is controlled by scan line 86. An inverter 34 is disposed between the transistor 30 and the output terminal _Vcom1, and inverts an input signal from the transistor 30. Other inverter 36 inverts the placed in the signal at the output terminal _{V com1} between the transistor 32 and the output terminal _{V com2.}

In operation, a frame signal V _in consisting of two fields 38 and 40 is input from transistor 30. Here, the time of each field is 1/60 second. When the transistor 30 is turned on by the scanning signal of the scanning line 84, the first field signal 38 is transferred to the inverter 34 through the transistor 30. The inverter 34 inverts the first field signal 38 and transmits the inverted first field signal 38 from the output terminal _Vcom1 to drive the common electrode 92. Next, when the transistor 32 is turned on by the scanning line 86, the inverted first field signal 38 is transferred to the inverter 36 through the transistor 32. The inverter 36 inverts the received signal again and transmits it from the output terminal _Vcom2 to drive the common electrode 94.

Therefore, according to the waveform generated by the driving circuit of the present invention, the switch transistor 16 of the pixel electrode 26 is turned on by the scanning signal of the scanning line 84. At the same time, the common electrode 92 is driven by a drive signal from the output terminal _Vcom1 . In this way, the waveform shown in FIG. 9A is formed, of which the waveform 204 is the signal at the output terminal _Vcom1 , and the waveform 202 is the signal at the scanning line 84.

Next, when the transistor 30 receives the signal of the scanning line 84 again, the second field signal 40 is transferred to the inverter 34 through the transistor 30. The inverter 34 inverts the second field signal 40 and transmits the inverted second field signal 40 from the output terminal _Vcom1 to drive the common electrode 92. Next, when the transistor 32 is turned on by the scanning line 86, the inverted second field signal 40 is transferred to the inverter 36 through the transistor 32. The inverter 36 inverts the received signal again and transmits it from the output terminal _Vcom2 to drive the common electrode 94.

Accordingly, the switch transistor 16 of the pixel electrode 26 is turned on by the scanning signal of the scanning line 84. At the same time, the common electrode 92 receives a signal from the output terminal _Vcom1 . In this way, the waveform shown in FIG. 9B is formed, of which the waveform 208 is the signal at the output terminal _Vcom2 , and the waveform 212 is the signal at the scanning line 84.

  On the other hand, the liquid crystal molecules filling the pixel region need to be aligned. This orientation aligns the orientation of the liquid crystal molecules before the electric field is applied to the liquid crystal display and ensures that all the liquid crystal molecules are aligned in the same direction. Align orientation using rubbing method. During the rubbing process, azimuth lines are generated on the alignment film. The liquid crystal molecules are aligned along their orientation lines.

  According to the present invention, the metal electrode is formed in the pixel region. The metal electrode is controlled by a common electrode. Liquid crystal molecules in all pixel regions are in a splay state. First, a voltage is applied to the metal electrode to change the liquid crystal molecules on the metal electrode from a splay state to a bend state during operation. Thereafter, a voltage is applied to the pixel electrode. That is, the liquid crystal molecules arranged on the metal electrode are first changed. However, when a voltage is applied to the common electrode, an unwanted lateral field is also generated around the common electrode. The lateral electric field affects the conversion of liquid crystal molecules arranged around the electric field. Therefore, the present invention provides an alignment method that reduces the influence of the lateral electric field.

  FIG. 13A is a schematic diagram showing liquid crystal molecules aligned perpendicular to the direction of the metal electrode. Liquid crystal molecules 746 disposed on the metal electrode 742 and the pixel electrode 744 are aligned in a direction perpendicular to the metal electrode 742 as indicated by an arrow 740. As shown in FIG. 5A, the metal electrode 812 is formed around the pixel electrode. Therefore, according to the alignment method shown in FIG. 13A, the liquid crystal molecules 818 arranged on the metal electrode 812 and the pixel electrode are aligned in a direction perpendicular to the metal electrode 812.

  FIG. 13B is a schematic diagram showing liquid crystal molecules affected by a lateral electric field. The lateral electric field 750 generated by applying a voltage to the pixel electrode 744 and the electric field 748 used to change the liquid crystal molecules 746 have opposite directions. In other words, a larger voltage must be applied to the pixel electrode 744 in order to overcome the lateral electric field and complete the change of the liquid crystal molecules 746. Since such a large voltage is required, energy and time are required to complete the change of the liquid crystal molecules.

  FIG. 14A is a schematic diagram showing liquid crystal molecules aligned parallel to the direction of the metal electrode. Liquid crystal molecules 746 disposed on the metal electrode 742 and the pixel electrode 744 are aligned in a direction parallel to the metal electrode 742 as indicated by an arrow 752. As shown in FIG. 5A, the metal electrode 812 is formed around the pixel electrode. Therefore, according to the alignment method shown in FIG. 14A, the liquid crystal molecules 818 arranged on the metal electrode 812 and the pixel electrode are aligned in a direction parallel to the metal electrode 812.

  FIG. 14B is a schematic diagram showing changes in liquid crystal molecules when a voltage is applied to the pixel electrode 744. As shown in FIG. 14A, the alignment direction of the liquid crystal molecules 746 is parallel to the alignment direction of the metal electrode 742. That is, the horizontal electric field generated by the metal electrode 742 does not hinder the change of liquid crystal molecules. That is, it is not necessary to apply a larger voltage to the pixel electrode 744 to overcome the disturbance of the lateral electric field.

  That is, the alignment direction of the liquid crystal molecules in the above-described embodiments is parallel to the arrangement direction of the metal electrodes. However, the arrangement direction of the metal electrodes is not always the same direction in the pixel region of the above-described embodiment, and this causes disorder in the alignment direction of the liquid crystal molecules in the pixel region. In order to solve this problem, a metal electrode is designed and an additional hole is provided at a position corresponding to the metal electrode or the common electrode through the pixel electrode, thereby reducing the influence of the lateral electric field and improving the transmittance. . The following eight embodiments show the pixel structure as a modification of FIG. 4A, and reduce the influence of the lateral electric field together with the alignment of the liquid crystal molecules.

  FIG. 15A is a schematic diagram illustrating the pixel structure of FIG. 4A changed by the alignment method of the first embodiment. A silicon island 706 a of the switch transistor 706 is connected to the scanning line 702. When the switch transistor 706 is selected, the scanning signal on the scanning line 702 turns on the switch transistor 706. The video signal on the video data line 704 is transferred to the pixel electrode 708 through the switch transistor 706. A drain electrode 706 b of the switch transistor 706 is connected to the pixel electrode 708. A source electrode 706 c of the switch transistor 706 is connected to the video data line 704. The common electrode line 710 is used as a common electrode for the pixel electrode 708. A metal electrode 756 is formed around the pixel region. The metal electrode 756 is controlled by the common electrode line 710. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  In order to make the alignment direction of the liquid crystal molecules parallel to the arrangement direction of the metal electrode 756, an additional hole 758 is further penetrated to the pixel electrode 708 and formed at a position corresponding to the common electrode line 710. The hole 758 is oval, rectangular or other shape having a major axis. The major axis direction must be parallel to the alignment direction of the liquid crystal molecules as indicated by an arrow 754. On the other hand, since the metal electrode 756 adjacent to the scanning line 702 has a sawtooth shape, the metal electrode 756 has a long axis in the direction indicated by the arrow 754. That is, liquid crystal molecules arranged on the metal electrode 756 adjacent to the scanning line 702 are aligned in the direction indicated by the arrow 754.

  FIG. 17A is a schematic diagram showing an enlarged portion of region 760 in FIG. 15A. A plurality of holes 758 penetrating the pixel electrode 708 are provided at positions corresponding to the common electrode line 710. According to a preferred embodiment, the hole 758 is oval. The liquid crystal molecules 718 disposed on the pixel electrode are aligned in a direction parallel to the long axis of the hole 758 as indicated by an arrow 754. Since the holes 758 are independent of each other, the holes 758 can be regarded as independent electrodes and have a long axis that generates a large lateral electric field in the direction indicated by the arrow 754. Accordingly, as shown in FIG. 17A, the liquid crystal molecules 718 are aligned in a direction parallel to the long axis of the hole 758, and the influence of the lateral electric field can be reduced. FIG. 17B is a schematic diagram showing liquid crystal molecules when a voltage is applied to the common electrode.

  FIG. 18A is a schematic diagram showing an enlarged portion of region 762 in FIG. 15A. The metal electrode 756 has a sawtooth shape. In this region 762, the metal electrode 756 includes a base portion 756a and a plurality of extending portions 756b. A part of the extending portion 756b protrudes from the pixel electrode 708. That is, the metal electrode 756 has a long axis that generates a large lateral electric field in the direction indicated by the arrow 754. Accordingly, the liquid crystal molecules 718 are aligned in a direction parallel to the long axis and the extending portion 756b, thereby reducing the influence of the lateral electric field as shown in FIG. 18A. FIG. 18B is a schematic diagram showing liquid crystal molecules when a voltage is applied to the common electrode.

  On the other hand, the region 764 and the region 762 have the same structure as the metal electrode 756 in FIG. 15A.

  FIG. 15B is a schematic diagram showing the pixel structure of FIG. 4A changed by the alignment method of the second embodiment. A silicon island 706 a of the switch transistor 706 is connected to the scanning line 702. When the switch transistor 706 is selected, the scanning signal on the scanning line 702 turns on the switch transistor 706. The video signal on the video data line 704 is transferred to the pixel electrode 708 through the switch transistor 706. A drain electrode 706 b of the switch transistor 706 is connected to the pixel electrode 708. A source electrode 706 c of the switch transistor 706 is connected to the video data line 704. The common electrode line 710 is used as a common electrode for the pixel electrode 708. A metal electrode 770 is formed around the pixel region. The metal electrode 770 is controlled by a common electrode line 710. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  The alignment direction of the liquid crystal molecules is parallel to the arrangement direction of the metal electrode 770, and the metal electrode 770 adjacent to the video data line 704 has a sawtooth shape, so that the metal electrode 770 has a major axis in the direction indicated by the arrow 766. . That is, the liquid crystal molecules are aligned in the direction indicated by arrow 766. On the other hand, since a part of the pixel electrode 708 in the pixel region is separated into two parts, a position corresponding to the common electrode line 710 is exposed. The main purpose is to align the liquid crystal molecules in the direction indicated by arrow 766.

  FIG. 19A is a schematic diagram showing an enlarged portion of region 768 in FIG. 15B. A groove penetrating the pixel electrode 708 is provided at a position corresponding to the common electrode line 710 to separate the pixel electrode into two parts. According to the preferred embodiment, the groove is rectangular with a major axis, which produces a large lateral electric field in the direction indicated by arrow 766. The liquid crystal molecules 718 arranged on the pixel electrode 708 are aligned in a direction indicated by an arrow 766 and are parallel to the common electrode line 710, so that the influence of a lateral electric field can be reduced. FIG. 19B is a schematic diagram showing liquid crystal molecules when a voltage is applied to the common electrode.

  On the other hand, similar to the display in FIG. 18A, the metal electrode 770 adjacent to the video data line 704 has a sawtooth shape. The metal electrode 770 has a plurality of extending portions outside the pixel electrode 708. These extensions produce a large lateral electric field in the direction indicated by arrow 766. That is, the liquid crystal molecules 718 are aligned in the direction indicated by the arrow 766.

  FIG. 15C is a schematic diagram showing the pixel structure of FIG. 4A changed by the alignment method of the third embodiment. A silicon island 706 a of the switch transistor 706 is connected to the scanning line 702. When the switch transistor 706 is selected, the scanning signal on the scanning line 702 turns on the switch transistor 706. The video signal on the video data line 704 is transferred to the pixel electrode 708 through the switch transistor 706. A drain electrode 706 b of the switch transistor 706 is connected to the pixel electrode 708. A source electrode 706 c of the switch transistor 706 is connected to the video data line 704. The common electrode line 710 is used as a common electrode for the pixel electrode 708. A metal electrode 772 is formed around the pixel region. The metal electrode 772 is controlled by the common electrode line 710. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  In order to make the alignment direction of the liquid crystal molecules parallel to the arrangement direction of the metal electrode 772, a plurality of additional holes 758 are passed through the pixel electrode 708 and formed at positions corresponding to the common electrode line 710. On the other hand, an additional hole 782 is passed through the pixel electrode 708 to form a position corresponding to the metal electrode 772 adjacent to the scanning line 702. The hole 758 is oval, rectangular, or other shape having a major axis. The major axis direction must be parallel to the alignment direction of the liquid crystal molecules as indicated by an arrow 754. On the other hand, the metal electrode 772 adjacent to the video data line 704 is outside the pixel electrode 708. According to the preferred embodiment, the alignment direction of the liquid crystal molecules is parallel to the direction indicated by the arrow 754.

  FIG. 20A is a schematic diagram showing an enlarged portion of region 784 in FIG. 15C. A metal electrode 772 adjacent to the video data line is outside the pixel electrode 708. According to the preferred embodiment, the metal electrode 772 outside the pixel electrode 708 has a major axis that generates a large lateral electric field in the direction indicated by arrow 754. Accordingly, the liquid crystal molecules 718 arranged on the pixel electrode 708 are aligned in the direction indicated by the arrow 754 and become parallel to the metal electrode 772 to reduce the influence of the lateral electric field. FIG. 20B is a schematic diagram showing liquid crystal molecules when a voltage is applied to the common electrode.

  On the other hand, similar to the display in FIG. 17A, a plurality of holes 758 are penetrated through the pixel electrode 708 and formed at positions corresponding to the metal electrodes 772 adjacent to the scanning lines 702. According to the preferred invention, the shape of the hole 758 is rectangular. However, in the preferred embodiment, other shapes having a major axis may be used. The liquid crystal molecules 718 disposed on the pixel electrode 708 are aligned in a direction parallel to the long axis of the hole 758 as indicated by an arrow 754.

  FIG. 15D is a schematic diagram illustrating the pixel structure of FIG. 4A changed by the alignment method of the fourth embodiment. A silicon island 706 a of the switch transistor 706 is connected to the scanning line 702. When the switch transistor 706 is selected, the scanning signal on the scanning line 702 turns on the switch transistor 706. The video signal on the video data line 704 is transferred to the pixel electrode 708 through the switch transistor 706. A drain electrode 706 b of the switch transistor 706 is connected to the pixel electrode 708. A source electrode 706 c of the switch transistor 706 is connected to the video data line 704. The common electrode line 710 is used as a common electrode for the pixel electrode 708. A metal electrode 774 is formed around the pixel region. The metal electrode 774 is controlled by the common electrode line 710. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  In order to make the alignment direction of the liquid crystal molecules parallel to the arrangement direction of the metal electrode 774, an additional hole 786 is passed through the pixel electrode 708 to form a position corresponding to the metal electrode 774 adjacent to the video data 704. The hole 786 is oval, rectangular, or other shape having a major axis. Note that the direction of the major axis must be parallel to the alignment direction of the liquid crystal molecules as indicated by the arrow 766. On the other hand, the metal electrode 774 adjacent to the scanning line 702 is outside the pixel electrode 708. A groove is passed through the pixel electrode 708 and formed at a position corresponding to the common electrode line 710.

  A metal electrode 774 adjacent to the scanning line 702 is outside the pixel electrode 708. According to the preferred embodiment, the metal electrode 774 outside the pixel electrode 708 has a major axis that generates a large lateral electric field in the direction indicated by arrow 766. Accordingly, similar to the display in FIG. 20A, the liquid crystal molecules arranged on the pixel electrode 708 are aligned in the direction indicated by the arrow 766 and become parallel to the metal electrode 774 to reduce the influence of the lateral electric field. .

  On the other hand, a groove penetrating the pixel electrode 708 is provided at a position corresponding to the common electrode line 710 to separate the pixel electrode into two parts. According to the preferred embodiment, the groove is rectangular with a major axis, which produces a large lateral electric field in the direction indicated by arrow 766. That is, the liquid crystal molecules arranged on the pixel electrode 708 are aligned in the direction indicated by the arrow 766.

  Further, similar to the display in FIG. 17A, a plurality of holes 786 penetrating the pixel electrode 708 are provided at positions corresponding to the metal electrode 774 adjacent to the video data line 704. According to the preferred embodiment, the holes 786 are rectangular, but other shapes having a major axis may be used in this embodiment. The liquid crystal molecules arranged on the pixel electrode 708 are aligned in a direction parallel to the long axis of the hole 786 as indicated by an arrow 766.

  FIG. 15E is a schematic view showing the pixel structure of FIG. 4A changed by the alignment method of the fifth embodiment. A silicon island 706 a of the switch transistor 706 is connected to the scanning line 702. When the switch transistor 706 is selected, the scanning signal on the scanning line 702 turns on the switch transistor 706. The video signal on the video data line 704 is transferred to the pixel electrode 708 through the switch transistor 706. A drain electrode 706 b of the switch transistor 706 is connected to the pixel electrode 708. A source electrode 706 c of the switch transistor 706 is connected to the video data line 704. The common electrode line 710 is used as a common electrode for the pixel electrode 708. A metal electrode 790 is formed around the pixel region. The metal electrode 790 is controlled by a common electrode line 710. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  In order to make the alignment direction of the liquid crystal molecules parallel to the arrangement direction of the metal electrode 790, an additional hole 758 is passed through the pixel electrode 708 and formed at a position corresponding to the common electrode line 710. The hole 758 is oval, rectangular or other shape having a major axis. The major axis direction must be parallel to the alignment direction of the liquid crystal molecules indicated by the arrow 754. On the other hand, since the metal electrode 790 adjacent to the scanning line 702 has a sawtooth shape, the metal electrode 790 has a major axis in the direction indicated by the arrow 754. That is, the liquid crystal molecules on the metal electrode 790 adjacent to the scanning line 702 are aligned in the direction indicated by the arrow 754. The main difference between the first embodiment and the fifth embodiment is that an additional hole 791 is passed through the pixel electrode 708 and formed at a position corresponding to the metal electrode 790 adjacent to the scanning line 702. The hole 791 is oval, rectangular, or other shape having a major axis. The major axis direction must be parallel to the alignment direction of the liquid crystal molecules as indicated by an arrow 754.

  A plurality of holes 758 penetrating the pixel electrode 708 are provided at positions corresponding to the common electrode line 710. According to the preferred embodiment, the hole 758 is rectangular. The liquid crystal molecules arranged on the pixel electrode are aligned in a direction parallel to the long axis of the hole 758 as indicated by an arrow 754 in FIG. 17A. Each hole 758 has a major axis that produces a large lateral electric field in the direction indicated by arrow 754. Accordingly, the liquid crystal molecules are aligned in a direction parallel to the long axis of the hole 758, and the influence of the lateral electric field can be reduced.

  Similar to the display in FIG. 18A, the metal electrode 790 adjacent to the scan line 702 is serrated. The metal electrode 790 has a plurality of extending portions 792 outside the pixel electrode 708. These extensions produce a large lateral electric field in the direction indicated by arrow 766. That is, the liquid crystal molecules 718 are aligned in the direction indicated by the arrow 766. On the other hand, a hole 791 is passed through the pixel electrode 708 and formed at a position corresponding to the metal electrode 790 adjacent to the scanning line 702. The hole 791 is oval, rectangular, or other shape having a major axis. The main purpose of forming the additional hole 791 is to reduce the influence of the lateral electric field generated by the scanning line 702.

  FIG. 15F is a schematic diagram showing the pixel structure of FIG. 4A changed by the alignment method of the sixth embodiment. A silicon island 706 a of the switch transistor 706 is connected to the scanning line 702. When the switch transistor 706 is selected, the scanning signal on the scanning line 702 turns on the switch transistor 706. The video signal on the video data line 704 is transferred to the pixel electrode 708 through the switch transistor 706. A drain electrode 706 b of the switch transistor 706 is connected to the pixel electrode 708. A source electrode 706 c of the switch transistor 706 is connected to the video data line 704. The common electrode line 710 is used as a common electrode for the pixel electrode 708. A metal electrode 792 is formed around the pixel region. The metal electrode 792 is controlled by a common electrode line 710. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  Since the alignment direction of the liquid crystal molecules is parallel to the arrangement direction of the metal electrode 792 and the metal electrode 792 adjacent to the video data line 704 has a sawtooth shape, the metal electrode 792 has a major axis in the direction indicated by the arrow 766. . That is, the liquid crystal molecules are aligned in the direction indicated by arrow 766. On the other hand, since a part of the pixel electrode 708 in the pixel region is separated into two parts, a position corresponding to the common electrode line 710 is exposed. The main purpose is to align the liquid crystal molecules in the direction indicated by arrow 766. The main difference between the second embodiment and the sixth embodiment is that an additional hole 793 is passed through the pixel electrode 708 and formed at a position corresponding to the metal electrode 792 adjacent to the video data line 704. The hole 793 is oval, rectangular or other shape having a major axis. Note that the direction of the major axis must be parallel to the alignment direction of the liquid crystal molecules as indicated by the arrow 766.

  Similar to the display in FIG. 19A, a groove penetrating the pixel electrode 708 is provided at a position corresponding to the common electrode line 710 to separate the pixel electrode into two parts. According to the preferred embodiment, the groove is rectangular with a major axis, which produces a large lateral electric field in the direction indicated by arrow 766. The liquid crystal molecules arranged on the pixel electrode 708 are aligned in the direction indicated by the arrow 766.

  On the other hand, similar to that shown in FIG. 18A, the metal electrode 792 adjacent to the video data line 704 has a sawtooth shape. The metal electrode 792 has a plurality of extending portions 794 outside the pixel electrode 708. These extended portions generate a large lateral electric field in the direction indicated by arrow 766. That is, the liquid crystal molecules are aligned in the direction indicated by the arrow 766. Further, an additional hole 793 penetrating the pixel electrode 708 is provided at a position corresponding to the metal electrode 792 adjacent to the video data line 704. According to the preferred embodiment, the holes 793 are rectangular, but other shapes having an elliptical shape or a major axis may be used in this embodiment. The main purpose of forming the additional hole 793 is to reduce the influence of the transverse electric field generated by the video data line 704. Liquid crystal molecules arranged on the pixel electrode 708 are aligned in a direction parallel to the long axis of the hole 793 as indicated by an arrow 766.

  FIG. 15G is a schematic view showing the pixel structure of FIG. 4A changed by the alignment method of the seventh embodiment. A silicon island 706 a of the switch transistor 706 is connected to the scanning line 702. When the switch transistor 706 is selected, the scanning signal on the scanning line 702 turns on the switch transistor 706. The video signal on the video data line 704 is transferred to the pixel electrode 708 through the switch transistor 706. A drain electrode 706 b of the switch transistor 706 is connected to the pixel electrode 708. A source electrode 706 c of the switch transistor 706 is connected to the video data line 704. The common electrode line 710 is used as a common electrode for the pixel electrode 708. Metal electrodes 795 are formed around the pixel region. The metal electrode 795 is controlled by the common electrode line 710. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  In order to make the alignment direction of the liquid crystal molecules parallel to the arrangement direction of the metal electrode 795, a plurality of holes 758 are passed through the pixel electrode 708 and formed at positions corresponding to the common electrode line 710. Further, a hole 758 is passed through the pixel electrode 708 and formed at a position corresponding to the metal electrode 795 adjacent to the scanning line 702. The main difference between the third embodiment and the seventh embodiment is that an additional hole 796 is formed between two adjacent holes 758. The holes 758 or 796 are oval, rectangular or other shapes having a major axis. The major axis direction must be parallel to the alignment direction of the liquid crystal molecules as indicated by an arrow 754.

  Similar to the display in FIG. 20A, the metal electrode 795 adjacent to the video data line 704 is outside the pixel electrode 708. According to the preferred embodiment, the metal electrode 795 outside the pixel electrode 708 has a major axis that generates a large lateral electric field in the direction indicated by arrow 754. Accordingly, the liquid crystal molecules arranged on the pixel electrode 708 are aligned in the direction indicated by the arrow 754 and become parallel to the metal electrode 795 to reduce the influence of the lateral electric field.

  Further, similar to the display in FIG. 17A, a plurality of holes 758 penetrating the pixel electrode 708 are provided at positions corresponding to the metal electrodes 795 adjacent to the scanning lines 702. Additional holes 796 are each formed between two adjacent holes 758. The main purpose of forming the additional hole 796 is to reduce the influence of the lateral electric field generated by the scanning line 702. The liquid crystal molecules arranged on the pixel electrode 708 are aligned in a direction parallel to the long axis of the hole 796 as indicated by an arrow 754.

  FIG. 15H is a schematic view showing the pixel structure of FIG. 4A changed by the alignment method of the eighth embodiment. A silicon island 706 a of the switch transistor 706 is connected to the scanning line 702. When the switch transistor 706 is selected, the scanning signal on the scanning line 702 turns on the switch transistor 706. The video signal on the video data line 704 is transferred to the pixel electrode 708 through the switch transistor 706. A drain electrode 706 b of the switch transistor 706 is connected to the pixel electrode 708. A source electrode 706 c of the switch transistor 706 is connected to the video data line 704. The common electrode line 710 is used as a common electrode for the pixel electrode 708. A metal electrode 797 is formed around the pixel region. The metal electrode 797 is controlled by a common electrode line 710. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  In order to make the alignment direction of the liquid crystal molecules parallel to the arrangement direction of the metal electrode 797, a plurality of holes 786 are passed through the pixel electrode 708 and formed at positions corresponding to the metal electrode 797 adjacent to the video data line 704. Further, additional holes 798 are formed between any two holes 786, respectively. The holes 786 or 798 are oval, rectangular or other shapes having a major axis. Note that the direction of the major axis must be parallel to the alignment direction of the liquid crystal molecules as indicated by the arrow 766. On the other hand, the metal electrode 797 adjacent to the scanning line 702 is outside the pixel electrode 708. Furthermore, since a part of the pixel electrode 708 in the pixel region is separated into two parts, a position corresponding to the common electrode line 710 is exposed.

  A metal electrode 797 adjacent to the scanning line 702 is outside the pixel electrode 708. According to the preferred embodiment, the metal electrode 797 outside the pixel electrode 708 has a major axis that produces a large lateral electric field in the direction indicated by arrow 766. Accordingly, similar to the display in FIG. 20A, the liquid crystal molecules arranged on the pixel electrode 708 are aligned in the direction indicated by the arrow 766 and become parallel to the metal electrode 797 to reduce the influence of the lateral electric field. .

  As shown in FIG. 19A, a groove penetrating the pixel electrode 708 is provided at a position corresponding to the common electrode line 710 to separate the pixel electrode into two parts. According to the preferred embodiment, the groove is rectangular with a major axis, which produces a large lateral electric field in the direction indicated by arrow 766. Accordingly, the liquid crystal molecules arranged on the pixel electrode 708 are aligned in the direction indicated by the arrow 766.

  Further, similar to the display in FIG. 17A, a hole 786 that penetrates the pixel electrode 708 is formed at a position corresponding to the metal electrode 797 adjacent to the video data line 704. Additional holes 798 are each formed between any two adjacent holes 786. The main purpose of forming the additional hole 798 is to reduce the effect of the transverse electric field generated by the video data line 704. The liquid crystal molecules arranged on the pixel electrode 708 are aligned in a direction parallel to the major axis of the hole 798 as indicated by an arrow 766.

  That is, the pixel structure of FIG. 4A that is applied to the above-described eight embodiments in which the pixel structure of FIG. 4A is changed by the alignment method to reduce the influence of the lateral electric field should be used for other types of structures. You can also. For example, the pixel structure as shown in FIG. 5A can be changed using the methods described in the following examples.

  FIG. 16A is a schematic diagram illustrating the pixel structure of FIG. 5A changed by the alignment method of the ninth embodiment. A silicon island 806 a of the switch transistor 806 is connected to the scanning line 802. A drain electrode 806 b of the switch transistor 806 is connected to the pixel electrode 808. A source electrode 806 c of the switch transistor 806 is connected to the video data line 804. The common electrode line 810 is used as a common electrode for the pixel electrode 808. An H-shaped pixel structure including the metal electrode 856 and the common electrode 810 is formed in the pixel region. The metal electrode 856 is controlled by a common electrode line 810. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  In order to make the alignment direction of the liquid crystal molecules parallel to the arrangement direction of the metal electrode 856, a plurality of additional holes 858 are passed through the pixel electrode 808 and formed at positions corresponding to the common electrode line 810. The hole 858 is oval, rectangular or other shape having a major axis. The major axis direction must be parallel to the alignment direction of the liquid crystal molecules as indicated by an arrow 854. On the other hand, the metal electrode 856 adjacent to the video data line 804 is outside the pixel electrode 808. Accordingly, the liquid crystal molecules disposed on the metal electrode 856 adjacent to the video data line 804 are aligned in the direction indicated by the arrow 854.

  Similar to the display in FIG. 20A, the metal electrode 856 adjacent to the video data line 804 is outside the pixel electrode 808. According to the preferred embodiment, the metal electrode 856 outside the pixel electrode 808 has a major axis that generates a large lateral electric field in the direction indicated by arrow 854. Accordingly, the liquid crystal molecules disposed on the pixel electrode 808 are aligned in the direction indicated by the arrow 854 and become parallel to the metal electrode 856 to reduce the influence of the lateral electric field.

  On the other hand, similar to the display in FIG. 17A, a plurality of holes 858 that penetrate the pixel electrode 808 are provided at positions corresponding to the common electrode line 810. According to the preferred embodiment, the holes 858 are rectangular, but other shapes having an ellipse or a major axis may be used. The liquid crystal molecules arranged on the pixel electrode are aligned in a direction parallel to the long axis of the hole 858 indicated by the arrow 854.

  FIG. 16B is a schematic diagram showing the pixel structure of FIG. 5A changed by the alignment method of the tenth embodiment. A silicon island 806 a of the switch transistor 806 is connected to the scanning line 802. A drain electrode 806 b of the switch transistor 806 is connected to the pixel electrode 808. A source electrode 806 c of the switch transistor 806 is connected to the video data line 804. The common electrode line 810 is used as a common electrode for the pixel electrode 808. An H-shaped pixel structure including the metal electrode 870 and the common electrode 810 is formed in the pixel region. The metal electrode 870 is controlled by a common electrode line 810. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  Since the alignment direction of the liquid crystal molecules is parallel to the arrangement direction of the metal electrode 870 and the metal electrode 870 adjacent to the video data line 804 has a sawtooth shape, the metal electrode 870 has a major axis in the direction indicated by the arrow 866. . That is, the liquid crystal molecules are aligned in the direction indicated by the arrow 866. On the other hand, since a part of the pixel electrode 808 in the pixel region is separated into two parts, a position corresponding to the common electrode line 810 is exposed. The main purpose is to align the liquid crystal molecules in the direction indicated by arrow 866.

  Similar to the display in FIG. 19A, a groove penetrating the pixel electrode 808 is provided at a position corresponding to the common electrode line 810 to separate the pixel electrode into two parts. According to the preferred embodiment, the groove is rectangular with a major axis, which produces a large lateral electric field in the direction indicated by arrow 866. Accordingly, the liquid crystal molecules arranged on the pixel electrode 808 are aligned in the direction indicated by the arrow 866, and since it is parallel to the common electrode line 810, the influence of the lateral electric field can be reduced.

  On the other hand, similar to the display in FIG. 18A, the metal electrode 870 adjacent to the video data line 804 has a sawtooth shape. The metal electrode 870 has a plurality of extending portions outside the pixel electrode 808. These extensions produce a large lateral electric field in the direction indicated by arrow 866. That is, the liquid crystal molecules are aligned in the direction indicated by the arrow 866.

  FIG. 16C is a schematic diagram showing the pixel structure of FIG. 5A changed by the alignment method of the eleventh embodiment. A silicon island 806 a of the switch transistor 806 is connected to the scanning line 802. A drain electrode 806 b of the switch transistor 806 is connected to the pixel electrode 808. A source electrode 806 c of the switch transistor 806 is connected to the video data line 804. The common electrode line 810 is used as a common electrode for the pixel electrode 808. An H-shaped pixel structure including the metal electrode 878 and the common electrode 810 is formed in the pixel region. The metal electrode 878 is controlled by a common electrode line 810. When controlling the liquid crystal display, a voltage is simultaneously applied to the common electrode and the metal electrode.

  Since the alignment direction of the liquid crystal molecules is parallel to the arrangement direction of the metal electrode 878 and the metal electrode 878 adjacent to the video data line 804 has a sawtooth shape, the metal electrode 878 has a major axis in the direction indicated by the arrow 880. . That is, the liquid crystal molecules are aligned in the direction indicated by the arrow 880. On the other hand, since a part of the pixel electrode 808 in the pixel region is separated into two parts, a position corresponding to the common electrode line 810 is exposed. The main purpose is to align the liquid crystal molecules in the direction indicated by arrow 880.

  Similar to the display in FIG. 19A, a groove penetrating the pixel electrode 808 is provided at a position corresponding to the common electrode line 810 to separate the pixel electrode into two parts. According to this preferred embodiment, the liquid crystal molecules disposed on the pixel electrode 808 are oriented in the direction indicated by the arrow 866, which is parallel to the common electrode line 810, thereby reducing the influence of the lateral electric field. .

  On the other hand, similar to the display in FIG. 18A, the metal electrode 878 adjacent to the video data line 804 has a sawtooth shape. The metal electrode 878 has a plurality of extending portions 874 outside the pixel electrode 808. Holes 876 are each formed in any two adjacent extensions 874 to reduce the effects of lateral electric fields generated by the video data lines 804.

  In addition, although all of the above-described embodiments are arranged on different layers from the metal electrode line connected to the common electrode line and the video data line, those embodiments are arranged in the metal electrode line connected to the common electrode line. And the video data line may be arranged on the same layer.

  That is, in the present invention, the orientation direction is made parallel to the metal electrode in order to reduce the transverse electric field generated during the liquid crystal molecule change. On the other hand, an additional hole is made to penetrate the pixel electrode and is formed at a position corresponding to the metal electrode or the common electrode to reduce the lateral electric field. The hole 858 is oval, rectangular or other shape having a major axis.

  As will be appreciated by those skilled in the art, the above description of preferred embodiments of the invention is illustrative of the invention and is not intended to limit the invention. Various modifications and similar arrangements are included within the spirit and scope of the appended claims. The claims should be construed most broadly to include such variations and similar structures. While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.

It is a schematic block diagram which shows the liquid crystal display using OCB mode in which a liquid crystal molecule is in a spray state. It is a schematic block diagram which shows the liquid crystal display using OCB mode in which a liquid crystal molecule is a bend state. The schematic block diagram of is shown. It is a pixel structure top view of thin-film transistor LCD. FIG. 2B is a cross-sectional view taken along line BB ′ of FIG. 2A showing that some of the liquid crystal molecules are in the splay state and some are in the bend state. FIG. 2B is a cross-sectional view along line BB ′ of FIG. 2A in which all liquid crystal molecules are in a splayed state. FIG. 3 is a plan view of a pixel region according to the first embodiment of the present invention. FIG. 3B is a cross-sectional view along line AA ′ of FIG. 3A in which all liquid crystal molecules are in a splayed state. FIG. 3B is a cross-sectional view along line AA ′ of FIG. 3A in which some of the liquid crystal molecules have been changed to a bend state. FIG. 6 is a plan view of a pixel region according to a second embodiment of the present invention. FIG. 4B is a cross-sectional view taken along line AA ′ of FIG. FIG. 4B is a cross-sectional view along line AA ′ of FIG. 4A in which some of the liquid crystal molecules have been changed to a bend state. FIG. 6 is a plan view of a pixel region according to a third embodiment of the present invention. FIG. 5B is a cross-sectional view along line AA ′ of FIG. 5A with all liquid crystal molecules in the splayed state. FIG. 5B is a cross-sectional view taken along line AA ′ of FIG. 5A in which some of the liquid crystal molecules are changed to a bend state. FIG. 10 is a plan view of a pixel region according to a fourth embodiment of the present invention. FIG. 6B is a cross-sectional view along line AA ′ of FIG. 6A in which all liquid crystal molecules are in a splayed state. FIG. 6B is a cross-sectional view along line AA ′ of FIG. 6A in which some of the liquid crystal molecules have been changed to a bend state. It is a top view of the pixel area | region where the metal electrode line connected to the common electrode line and the video data line are arrange | positioned at the same layer. FIG. 7B is a cross-sectional view along line AA ′ of FIG. 7B in which some of the liquid crystal molecules have been changed to a bend state. It is a wave form diagram which shows the waveform from negative to positive of the drive timing by 1st Example. It is a wave form diagram which shows the waveform from the positive to the negative of the drive timing by 1st Example. It is a wave form diagram which shows the waveform from the negative to the positive of the drive timing by 2nd Example. It is a wave form diagram which shows the waveform from the positive to the negative of the drive timing by 2nd Example. It is a wave form diagram which shows the waveform from the negative to the positive of the drive timing by 3rd Example. It is a wave form diagram which shows the waveform from the positive to the negative of the drive timing by 3rd Example. It is the top view which used the pixel electrode structure of this invention for TFT-LCD. It is the schematic of the drive circuit which produces | generates a drive voltage. FIG. 2 shows a detailed view of a drive circuit that generates a drive voltage. It is the schematic of the liquid crystal molecule orientated in the direction perpendicular | vertical to a metal electrode. A schematic view of liquid crystal molecules affected by a lateral electric field is shown. The schematic of the liquid crystal molecule aligned in the direction parallel to a metal electrode is shown. It is the schematic of the liquid crystal molecule influenced by the horizontal electric field. It is a schematic block diagram which shows what changed the pixel structure of FIG. 4A with the orientation method by 1st Example. It is a schematic block diagram which shows what changed the pixel structure of FIG. 4A with the orientation method by 2nd Example. It is a schematic block diagram which shows what changed the pixel structure of FIG. 4A with the orientation method by 3rd Example. It is a schematic block diagram which shows what changed the pixel structure of FIG. 4A with the orientation method by 4th Example. It is a schematic block diagram which shows what changed the pixel structure of FIG. 4A with the orientation method by 5th Example. It is a schematic block diagram which shows what changed the pixel structure of FIG. 4A with the orientation method by 6th Example. A schematic diagram is shown. It is a schematic block diagram which shows what changed the pixel structure of FIG. 4A with the orientation method by 7th Example. A schematic diagram is shown. It is a schematic block diagram which shows what changed the pixel structure of FIG. 4A with the orientation method by 8th Example. It is a schematic block diagram which shows what changed the pixel structure of FIG. 5A with the orientation method by 1st Example. It is a schematic block diagram which shows what changed the pixel structure of FIG. 5A with the orientation method by 2nd Example. It is a schematic block diagram which shows what changed the pixel structure of FIG. 5A with the orientation method by 3rd Example. It is a top view which shows the hole which is arrange | positioned at a pixel electrode and exposes the metal electrode to which the voltage is not applied. It is a top view which shows the hole which is located in a pixel electrode and exposes the metal electrode to which the voltage is applied. It is a top view which shows the sawtooth-shaped metal electrode to which the voltage is not applied. It is a top view which shows the sawtooth-shaped metal electrode to which the voltage is applied. It is a top view which shows forming the groove | channel which exposes the common electrode to which the voltage is not applied in a pixel electrode. It is a top view which shows forming the groove | channel which exposes the common electrode to which the voltage is applied to a pixel electrode. It is a top view which shows the metal electrode extended | stretched from the pixel electrode to which the voltage is not applied. It is a top view which shows the metal electrode extended | stretched from the pixel electrode to which the voltage is applied.

Explanation of symbols

14, 16, 18, 19, 506, 706, 806, 906 Switch transistors 80, 82, 84, 86, 88, 302, 502, 702, 802, 902 Scan lines 12, 24, 26, 28, 29, 508, 508a, 508b, 708, 744, 808, 908 Pixel electrode 70, 72, 74, 304, 504, 704, 804, 904 Video data line 90, 92, 94, 96, 510, 710, 810, 910 Common electrode (line )
30, 32, 42, 44, 46, 48 Transistor 34, 36 Inverter 38 First field signal 40 Second field signal 202, 402, 212, 412, 602, 612 Scan signal 204, 208, 404, 408, 604 , 608 Voltage signal 206, 210, 406, 410, 606, 610 Pixel potential 506a, 706a, 806a, 906a Silicon island 506b, 706b, 806b, 906b Drain electrode 506c, 706c, 806c, 906c Source electrode 512, 712, 742, 756, 770, 772, 774, 790, 792, 795, 797, 812, 856, 870, 878, 912 Metal electrodes 514, 714, 814, 914 Lower substrate 516, 716, 816, 916 Upper substrate 518, 718, 8 18, 918 Liquid crystal layers 518a, 718a, 746, 818a, 918a Liquid crystal molecules 520, 720, 820, 920 Conductor electrodes 524, 526 Regions where pixel electrodes and metal electrodes overlap 530, 532, 730, 732, 830, 832 Isolation layers 740, 752, 754, 766, 776, 778, 854, 886, 880 Arrow 748, 750 Electric field 756a Base 756b, 792, 794, 874 Extension 758, 780, 782, 786, 791, 793, 796, 798, 858 , 876 hole 760, 762, 764, 768, 784 region

Claims (10)

A plurality of scan lines and a plurality of video data lines are provided, and any adjacent scan line and any adjacent video data line define a pixel region, and each pixel region is connected to a transistor and the transistor A first substrate having a pixel electrode;
A plurality of common electrode lines disposed under the pixel electrode;
A plurality of metal wires extending from the common electrode wire;
A plurality of holes penetrating through the pixel electrode and positioned above the metal line or the common electrode line, each of the pixel electrodes having at least one of the holes, each having a long axis; ,
A second substrate separated from the first substrate by a predetermined distance;
A conductor electrode located on the second substrate and generating an electric field between the metal line;
A liquid crystal molecule film sandwiched between the conductor electrode, the pixel electrode, and the metal line, wherein the liquid crystal molecule between the conductor electrode and the metal line has a predetermined electric field with the conductor electrode and the metal line. When established between the metal wire and the splay alignment mode, the bend alignment mode is changed.
The video data line, the common electrode line and the metal line are in the same layer, and the extending direction of the metal line located above the hole is parallel to the alignment direction of the liquid crystal molecules.
A pixel structure of a liquid crystal display.   The pixel structure of claim 1, wherein the video data line and the common electrode line are orthogonal to each other.   The pixel structure according to claim 1, wherein an alignment direction of the liquid crystal molecules is parallel to the major axis.   The pixel structure according to claim 1, wherein the hole is rectangular or elliptical.   2. The pixel structure according to claim 1, wherein the metal line adjacent to the video data line has a sawtooth shape.   The pixel structure according to claim 1, wherein the metal line adjacent to the scan line has a sawtooth shape.   2. The pixel structure according to claim 1, wherein the metal line or the common electrode line on which the hole is located is parallel to the major axis.   The pixel structure according to claim 1, wherein the alignment direction of the liquid crystal molecules is parallel to the major axis.   The pixel structure according to claim 1, wherein the metal line is orthogonal to the common electrode line.   2. The pixel structure according to claim 1, wherein a part of the metal line is perpendicular to the common electrode line, and another part is parallel to the common electrode line.