TW200811801A - Liquid crystal display and pixel driving method thereof - Google Patents

Abstract

A liquid crystal display (LCD) and a pixel driving method thereof are provided. In the present invention, a multiplexer is inserted between a data driver and a pixel circuit, and used to selectively output a precharge voltage or a driving voltage to two frame buffers of the pixel circuit. Therefore, a liquid crystal unit is precharged between every two frames, so as to accelerate the response speed. The present invention controls the precharge voltage supplied to the pixel circuit without adding new electronic devices to the pixel circuit, such that the cost of the circuit can be substantially saved.

Description

200811801 niy^uu6-0014-TW 19654twf.doc/006 IX. Description of the Invention: [Technical Field] The present invention relates to a liquid crystal display and a pixel driving method thereof, and more particularly to a single crystal stone The liquid crystal display (LCOS) liquid crystal display and the pixel driving method thereof can effectively accelerate the reaction speed of the liquid crystal display of the liquid crystal display and improve the display quality of the liquid crystal display.

[Prior Art] A liquid crystal display (LCD) has recently been widely used in a liquid crystal panel composed of a color light-emitting substrate and an active device array substrate. The characteristics of the coefficient of incidence (Birefringence), in the field; thousand = liquid crystal molecules in the panel turn, and then change the transmittance of the liquid crystal panel to achieve the purpose of development. , using 'and replacing the cathode ray tube display (CRT) as one of the main streams of the next generation of displays. With the improvement of semiconductor technology, the liquid crystal display has the advantages of low power consumption, light weight, high resolution, high color saturation and long life, so it is widely used in computer LCD screens and LCD TVs (LCD τν). Waiting for the electronic products on the side of life. Among them, the liquid crystal panel (Liquid Crystal Panel) is the key to the quality of the liquid crystal display. 5 200811801 ηι々·ό-0014-TW 19654twf.doc/006, there will be residual images. That is, the image data transmitted to £(::::>1 is faster than the LCD display, and the reaction of the liquid crystal in the LCD monitor cannot be kept up. ° Figure 1 shows Know the operation sequence diagram of the liquid crystal display. Please refer to Figure 1 'The liquid crystal display shows the working time of one frame (frame) is equal to eight sub-frame segments, including red square (R) sub-written = Segment, green field (G) sub-section, and blue field (B) sub-section. Among them, each sub-section is further cut into 3 segments, which contain data addressing for each pixel. (data addressing), liquid crystal reaction (LC response) and light display (light 〇n). Generally speaking, in the R sub-surface section, it is necessary to address the data of the ruler, and then wait for twinning. Anti-weaving, will show r light: same, ground, in the G or B section, you must first address the G ^ B pixel data, and the special G or B liquid crystal reaction, will show G light or B light. However, when the resolution of the liquid crystal display is increased, the frame update rate (frame mte) must also increase. This will cause the (4) material addressing speed and the liquid crystal transition speed to be insufficient. In order to improve this problem, the conventional method is to display the liquid crystal display! I's the 内 内 内 内 内 内 ( ( ( (10) in a certain color 昼The liquid crystal reaction and the light display period of the surface perform the data addressing operation of another color sub-picture. Therefore, after the color is displayed, the u color sub-picture can be displayed immediately:: This can save the data address. The time spent, and solve the problem of insufficient data addressing speed. 6 200811801 niy-zuuo-0014-TW 19654twf.doc/006 ® 2 The edge is shown in the operation sequence of the conventional liquid crystal display. Please refer to Figure 1 and Figure 2 at the same time. After adding the frame buffer to the pixel of the liquid crystal display, the data addressing time of the liquid crystal display pixel can be increased to a complete sub-picture time, and the original sub-surface only needs to be cut into liquid crystal reaction and light display. There are no 2 clips. This can make up for the shortcomings of the low speed of the data of the alizarin, and thus improve the display quality of the liquid crystal display. In addition, in the operation of the liquid crystal display H, in addition to constantly Data = halogen f pole * negative polarity charging to positive polarity, then * positive polarity discharge to negative electrode + Bu: The method of witnessing also includes the use of frame and column conversion handover blank time, way, early charging and discharging action ' In order to gain time, we will rely on electric power. In order to achieve 剌 _ first charge efficiency, we must mention the design of the circuit, and add many circuit components, so we must provide a drive circuit design that can effectively improve the liquid crystal reverse. In view of the above, the object of the present invention is to provide a liquid crystal display crying. At least two buffer reservoirs are added to the secondary liquid between the data driver and the halogen circuit. Take at every charge. Before the 7L change reception _ voltage, the liquid crystal cell is pre-contained for a plurality of purposes. The liquid crystal display provided by the present invention provides a driving voltage for each of the multi-work squeezing coupling mother-sucks driving, and the light is 4 Connect to - pre-charge voltage and corresponding data driver for 200811801 mj-zuu6-0014-TW 19654twf.doc/006

Selectively output the pre-charge voltage or the drive voltage provided by the data driver to the corresponding data line. The pixel array includes a plurality of pixel circuits, which are connected to the data lines of the ^, and each of the halogens contains at least two ship scales and liquids ^. The two buffer memories are coupled to the corresponding data lines for receiving the driving voltages provided by the pre-charge voltage or data driving! The liquid crystal cell comprises a pixel electrode, a liquid crystal molecular layer sandwiched between the pixel electrode and the common electrode=, wherein the halogen electrode is selected to be correspondingly buffered, and the liquid crystal display according to the preferred embodiment of the present invention is used. A pixel circuit further includes a f„m third off, and a third switch: wherein the first-off is coupled between the corresponding #feed line and the corresponding buffer memory. Between the memory and the corresponding halogen electrode; the third 卩 is reduced to the corresponding data coil corresponding to the buffer memory between the 'the fourth switch _ is connected between the corresponding buffer and the corresponding halogen electrode From another point of view, the present invention provides a pixel driving method, in which the liquid crystal display of the present invention is included, and the at least two buffer buffers include first and second buffer memories, and the halogen The driving method includes the following steps: in the first stage, the first switch and the fourth switch, the first switch and the third switch are turned on, and the corresponding multiplexer output is driven to the data line to store the driving voltage in the first step. a buffer memory, by the first The second buffer stores the H output f to the liquid crystal cell. On the first day, the third switch and the fourth switch are turned on, and the first switch and the second switch are turned off. 200811801 .xx.^uvo-0014-TW 19654twf.doc/006 And controlling the corresponding multiplexer to output the pre-charge voltage to the data line, and pre-charging the crystal unit. The pixel driving method according to the preferred embodiment of the present invention further includes the following steps: when the third stage is started, The second switch and the third switch 匕 the fourth switch ′ and control the corresponding multiplexer output drive power 1 to the top line to store the driving voltage in the second buffer, and the 5:: buffer output voltage is Liquid crystal cell. In the first step: Hi-switch and second switch, and close the third blue switch and the fourth open switch ^ Asia: read the multiplexer output pre-charge light to the data line, to the liquid兀 Pre-charging. τ From the perspective of brackets, the present invention provides a liquid crystal display, a package, a battery, a data driver, and a multiplexer, wherein: a channel: a storage device, and The data line is coupled to the second power supply ^ίί11 series to provide the driving voltage 'and more The device is connected to the power converter to selectively rotate the pre-charge voltage or the crane-to-data line provided by the bellows drive. The liquid crystal display according to the two preferred embodiments, the above-mentioned at least The tth includes first and second buffer memories, and the second switch, the third switch, and the fourth switch of the halogen circuit are switched between the first line and the second buffer, and the fourth switch is _ Between the younger brother and the _ 翻 昼 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 9 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 001 The Guanjia people are 4, and they are in the buffer memory 'to the ^ two buffers' so that before each of the liquid crystal cells rotates to receive the driving voltage (that is, between every two sides), The guard device relies on the switching signal to output the pre-charge voltage or the power-switching circuit, and the circuit charges the liquid crystal unit in the county, without having to add the circuit components in the pixel circuit, and then can record the crystal in the ground.

The display quality of the crystal display. The above and other objects, features and advantages of the present invention will become more apparent. [Embodiment] FIG. 3 is a circuit diagram of a liquid crystal display according to a preferred embodiment of the present invention. Please refer to item 3 'liquid crystal display 300 (for example, liquid crystal on silicon display) including a plurality of data drives 3 301 plural multiplexes 303, a plurality of gate drivers 3 still, and 昼Prime array 307. In this embodiment, the data driver 3^ provides the driving voltage Vd, and each of the multi-guards 3G3 corresponds to the data driving 301 and a data line DL, and receives the driving voltage Vd and the pre-charging voltage Vrst. And switching signal SW. The multiplexer 3〇3 selectively outputs the precharge voltage Vrst or the driving voltage Vd to the corresponding data line DL according to the switching of the second SW. • Gate driver The 305 series provides a scanning signal (9) and transmits the scanning signal 200811801 ηυ-ζυυό-0014-TW 19654twf.doc/006 to the pixel array 307 through a plurality of scanning lines SL1 and SL2. The internal pixel circuit 307a. Fig. 4 is a circuit diagram of the pixel circuit 307a of the present embodiment. Referring to FIG. 3 and FIG. 4 together, the pixel circuit 307a includes two buffer memories C1 and C2, a liquid crystal cell LC', and switches sp, dp, SN and DN. The buffer memories C1 and C2 are used to selectively receive the pre-charge voltage vrst or the drive voltage vd, and the buffer memories C1 and C2 are, for example, capacitors (capacit〇r), but the scope is not limited herein. The user may use other different types of storage elements as needed. In addition, in the pixel circuit 3〇7a of the embodiment, two buffers are stored as C1 and C2 as frame buffers to increase the data addressing time of the pixel circuit 307a. However, in this case, the number of users is used, and the user uses more than two buffer storages as needed. The liquid day unit LC includes a halogen electrode (pixei eiectr〇 (je, not shown), a common electrode (not shown), and a liquid crystal molecular layer sandwiched between the common electrode of the electrode (LC) The sinking electrode is selectively connected to the buffer memory C1 and the therein. The switch sp _ is connected between the data line DL and the buffer memory ci ^, and the switch DP is The surface is connected between the buffer reservoir α and the halogen electrode; the switch SN is connected between the data line sink and the buffer reservoir C2, and the switch DN is connected between the buffer reservoir a and the halogen electrode. Sp and (10) are respectively controlled by the corresponding sweep control line (1) material L2 DN is divided into the corresponding U and the switches SP, DP, SN and DN are gold 11 200811801 η^-ζυυο-0014-TW 19654twf. Doc/006 is an MOS transistor, but the scope is not limited herein. The user may use other different types of switches as needed. In order to more clearly illustrate the liquid crystal display 3 of the above embodiment. The effect of sputum, the following will cite a method of driving a scorpion, with the above The circuit structure of the liquid crystal display device of the embodiment is described by a single data driver 301, a multi-mode 303, a gate driver 305, and a pixel circuit 307 & and is divided into four stages to describe the liquid crystal display. 3 7 昼 电路 _ _ 3j7a operation flow, and the field of the present invention can be based on the teachings of the present embodiment, and analogous to the liquid crystal display 3 昼 昼 阵列 阵列 〇 昼 昼 昼 昼Figure 5 is a circuit diagram of the liquid crystal display of the present embodiment. Figure 6 is a flow chart of a method for driving a pixel in accordance with a preferred embodiment of the present invention. Figure 7, 7Β, 7C, 7D respectively The schematic diagram of the operation of the pixel circuit 307a of the first stage, the second stage, the third stage and the fourth stage of the driving method of the method according to the preferred embodiment of the present invention is shown in FIG. 5 and FIG. And in FIG. 7A, as described in step S601, in the first stage, the gate driver 305 provides a scan signal and turns on the switches SP and DN through a line SL1 and SL2 (ie, the standard in FIG. 7A, the latter). 'And close the switch 81^ and 1) 1) (also marked For the X), and the multiplexer 3〇3 selects to drive the voltage: d to the data line DL according to the received switching signal SW, and stores the driving voltage Vd in the buffer, the memory ci, At the same time, the buffer memory C2 outputs the driving voltage Vd stored therein to the liquid crystal cell lc. Next, please refer to FIG. 5, FIG. 6 and FIG. 7B. In the second stage, the gate driver 305 provides scanning in step S602 12-------0014-TW 19654twf.doc/006. The signal, and the switches SN and DN (i.e., the ones indicated in Figure 7B) are turned on by the % lines SL1 and SL2, and the switches SP and DP (i.e., labeled X) are turned off. At this time, the multiplexer 303 outputs the precharge voltage Vrst to the data line DL' according to the received switching signal sw and follows the arrow path of Fig. 7B to precharge the liquid crystal cell LC. Then, please refer to FIG. 5, FIG. 6 and FIG. 7C. In step S603, in the third stage, the gate driver 3〇5 will provide a scan signal, and the sister will open the switch SN through the scan lines SL1 and SL2. Dp (also labeled as the latter in Figure 7C), and the switch SP and ON (also labeled as X) are turned off. At this time, the multiplexer 303 outputs the driving voltage Vd to the data line DL according to the received switching signal sw, and stores the driving voltage Vd in the buffer memory C2. At the same time, the buffer memory C1 has stored the driving voltage Vd′ in step S6〇1. Therefore, when the switch DP is turned on, the stored driving voltage Vd is output to the liquid crystal cell LC, and the liquid crystal cell Lc is already in step S6. 〇2 input • Pre-charging is performed, so that the halogen electrode of the liquid crystal cell LC can quickly increase the driving voltage Vd stored in the buffer memory ci, so the reaction speed of the liquid crystal cell LC is accelerated.曰0 Finally, please refer to FIG. 5, FIG. 6 and FIG. 7D together. In step 4, in the fourth stage, the gate driver 3〇5 will provide a scan signal, and the scan lines SL1 and SL2 will be turned on. The switches sp and Dp (that is, the one shown in FIG. 7D) are turned off, and the switches 汹 and 咐 are also marked as X. At this time, the multiplexer 303 outputs the pre- 13 according to the received switching signal sw. 200811801 ni^ -zuuo-0014-TW 19654twf.doc/006 Charge M VrSt to data line DL and pre-charge the liquid crystal cell LC according to the arrow path of Figure 7D. In the above embodiment, the halogen driving method is divided into four stages, but the order of the respective steps S601 to S604 is not limited. For example, the pixel driving method of the embodiment may also start from step S6〇3, and step S604-S601-S602 is performed in sequence, and then back to step 〇3. In this embodiment, the pixel driving method sequentially cycles through steps S601 to S604 to cause the pixel device 307a to precharge the liquid crystal cell between every two time periods. The liquid crystal reaction speed of the liquid crystal cell lc is accelerated (that is, the liquid crystal transition speed is accelerated). Thereby, the display quality of the liquid crystal display device 300 is further improved. In summary, the present invention provides a liquid crystal display and a pixel driving method thereof. According to the above embodiment, the present invention has at least the following advantages: 9 Inflammation 1. By adding a multiplexer between the data driver and the pixel circuit, and selectively outputting the precharge voltage or the driving voltage to the morpheme The circuit, without having to add additional circuit components to the pre-charge voltage per ring (four) circuit, can achieve the effect of pre-charging and speeding up the reaction, which can greatly reduce the circuit cost. 2. Two buffer memories can interactively perform data addressing and rounding steps, and increase the data addressing time of the pixel circuit. 3. When the resolution of the liquid crystal display is increased, and the ftame rate is also increased, the liquid crystal cell is precharged between each two sides to accelerate the liquid crystal reaction speed of the liquid crystal cell. Lift LCD 14 200811801 (10) ό-0014-TW 19654twf.doc/006 Display quality of the display. Although the present invention has been disclosed in the preferred embodiment as above, the iron defines the date of the hair, and any mature New Zealand #, in the single material and the consumption, can make some changes and retouching, so the present invention = range when This is subject to the definition of the scope of the patent application. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 and FIG. 2 are schematic diagrams showing the operation sequence of a conventional liquid crystal display. 3 is a circuit diagram of a liquid crystal display according to a preferred embodiment of the present invention. FIG. 4 is a circuit diagram of a pixel circuit of the present embodiment. FIG.昼 驱动 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照 依照Schematic diagram of the second phase and the fourth phase of the pixel circuit operation. One U-hand Hanle [main component symbol description] 300: liquid crystal display 301: data driver 303: multiplexer 305 · gate driver 307: pixel array 3〇7a: pixel circuit SP, DP, SN, DN: switch 15 200811801 x υυ-ΟΟ 14-TW 19654twf.doc/006 a, C2: buffer memory LC: liquid crystal cells S601 to S604: preferred in the present invention Embodiment steps of the flow chart of the halogen driving method illustrated in the embodiment

16

Claims (1)

200811801 -0014-TW 19654twf.doc/006 Patent application scope: 1. A liquid crystal display comprising: pressing a plurality of data drivers, each of which provides a drive for a plurality of data lines; a plurality of multiplexers The multiplexer is coupled to a pre-charge voltage and a corresponding data driver for selectively outputting the pre-charge voltage to the corresponding data line; and a pixel array comprising a plurality of pixel circuits, Each of the pixel circuits is divided into: a plurality of buffer circuits, including: at least two buffer memories coupled to the corresponding data line (DL), selectively receiving the pre-charge voltage or a driving voltage; and a liquid crystal cell comprising a halogen electrode, a common electrode, and a liquid crystal molecular layer sandwiched between the halogen electrode and the common electrode, wherein the halogen electrode is connected to the liquid crystal layer The liquid crystal display of the invention of claim 2, wherein the pixel circuit further comprises: ': first-off' _ corresponding to the material line and corresponding The buffer Between the survivors, the gold reservoir and the corresponding Μ 极 极 - - - - - - - - - - - - - - - - 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 2008 The fourth switch is coupled between the corresponding buffer memory and the corresponding pixel electrode. The liquid crystal display according to claim 1, wherein the buffer storage device comprises a capacitor. ^ 5. The liquid crystal according to the patent application scope The display also includes: a plurality of gate drivers, each of the gate drivers providing a scan voltage; and a plurality of scan lines coupled to the corresponding gate drivers and the pixel circuits. ^ ^ Spoon 6:11^ Full-length liquid crystal display according to items 2 and 5 ' =; == line: the second and fourth open relationship ΐ line control. Work knowledge - and third open relationship The corresponding sniffering method includes a first and a second closing of the second opening 】=the first switch and the fourth switch, the buffer storage device, the same voltage is stored in the first unit; a buffer memory output voltage to the liquid 18 200811801 iiy 厶ν/ν/ vi-0014-TW 19654twf.doc/006 In a second phase, the third switch and the fourth switch are turned on, and the first is turned off a switch and the second switch, and controlling the corresponding multiplexed crying wheel to pre-charge the pre-charge to the data line to pre-charge the liquid crystal cell. 8 as described in claim 7 The method further includes the following steps: / ^ in a third phase, turning on the second switch and the third switch, turning off the first switch and the fourth switch, and controlling the corresponding multiplexer to output the driving Voltage is applied to the data line to store the driving voltage in the second buffer memory, and The first buffer memory outputs a voltage to the liquid crystal unit; and in a fourth stage, the first switch and the second switch are turned on, the third switch and the fourth switch are turned off, and the corresponding control is controlled The multiplexer outputs the pre-charge voltage to the data line to pre-charge the liquid crystal cell. 9. A liquid crystal display comprising: a pixel circuit comprising at least two buffer memories; a data line coupled To the halogen circuit; a cultivating driver providing a driving voltage; and a multiplexer 'coupled to a pre-charging voltage and the data driver for selectively outputting the pre-charging voltage or the driving voltage to the data The liquid crystal display of claim 9, wherein the at least one buffer memory comprises a first and a second buffer memory, and the pixel circuit further comprises: a first switch, Coupling between the data line and the first buffer memory; 19 200811801 x ixy-z.vuu-0014-TW 19654twf.doc/006; m _ in the first-buffer storage crying with the halogen electrode between; 2 three switches '_ between the transfer line and the second buffer reservoir: a fourth switch connected to the second buffer reservoir and the halogen electrode η. The liquid crystal according to claim 10 It is shown that the switches are metal oxide semiconductor transistors. σ° /, 12. The liquid crystal display according to claim 9, the buffer storage (Cb C2) includes a capacitor. 3. The liquid crystal display of claim 9, further comprising a plurality of pixel circuits, and the buffer memories comprise at least two framebuffers. - 20