A driving method of a large-size multi-color reflective LCD

Abstract

The application discloses a driving method of a large-size multi-color reflective LCD, comprising the following steps: S1, a common electrode applies a first voltage to a pixel, and a data line applies a second voltage to the pixel; S2, the common electrode applies a third voltage to the pixel, and the data line applies the second voltage to the pixel; S3, XON is turned on, a gate drive sends a signal to turn on all scanning lines, all pixels are turned on, a source drive sends a signal to input a voltage to all data lines, the data line simultaneously applies the second voltage to all pixels, and the common electrode simultaneously applies a fourth voltage to all pixels, wherein the first voltage, the second voltage, the third voltage and the fourth voltage are different from each other. The driving method provided by the application can reduce the charging time of the reflective LCD pixel, thereby reducing the load, improving the frame rate, and being especially suitable for a large-size reflective LCD. Moreover, due to the dynamic adjustment of the pixel charging voltage, more display colors can be excited, and the method can also be suitable for a multi-color reflective LCD.

Description

Technical Field

[0001] This invention relates to the field of display technology, and in particular to a driving method for a large-size multicolor reflective LCD. Background Technology

[0002] Currently, based on the type and arrangement of the light source used in liquid crystal display (LCD) panels, they can be classified into transmissive LCD panels, reflective LCD panels, and semi-transmissive / semi-reflective LCD panels. Reflective LCD panels primarily achieve display by reflecting light incident upon them. In related technologies, a reflective LCD panel generally includes two opposing substrates, a polarizer, and cholesteric liquid crystal molecules filling the space between the two substrates. Applying a voltage to the upper and lower substrates controls the rotation direction of the liquid crystal molecules, refracting the backlight provided by the backlight module of the display panel to display the image. When the liquid crystal molecules in the cholesteric liquid crystal layer deflect, light can pass through and be reflected. Reflective LCDs exhibit bistable characteristics, consuming no energy while maintaining the image, and requiring very low energy when the display changes. Reflective screens use ambient light and sunlight as their primary light source, illuminating the screen by reflecting external light sources; the stronger the sunlight, the clearer the screen, without consuming additional power. Therefore, reflective LCDs are characterized by their thinness, energy efficiency, and eye-friendliness. Given the many advantages of reflective LCDs, there is an increasing market demand for large-size, multi-color reflective LCDs.

[0003] The driving timing of a reflective LCD is divided into three states: A, B, and C. State A is the reflective state; when activated, the reflective LCD reflects ambient light, and the screen displays white. State B is an intermediate transition state, preparing for state C to activate. State C is the transparent state; when activated, the reflective LCD transmits ambient light, and the screen displays black. In existing technology, when a reflective LCD enters the reflective display state, the gate driver sequentially activates the pixels row by row according to the timing sequence, while the source driver simultaneously charges the pixels row by row according to the timing sequence. For example... Figure 1 The diagram shows the driving timing of a 10.3-inch reflective LCD using an existing driving method. In this method, the common voltage is 1V, the data line voltage is 15V, only one polarity change occurs in the reflective state, and the absolute value of the voltage remains the same. The time required to complete charging is 10fs (positive) + 10fs (negative), totaling 20fs. Furthermore, because the charging voltage remains constant, only one color can be activated for display.

[0004] Existing reflective LCDs generally suffer from long refresh times and poor driver timing compatibility. This is especially true for large-size reflective LCDs, where the RC loading is 4 to 5 times that of smaller LCDs (32 inches compared to 10.3 inches), resulting in longer pixel charging times and slower refresh rates, which cannot meet the market's increasingly demanding display performance requirements. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a driving method for a large-size multi-color reflective LCD, which can effectively shorten the pixel charging time of the large-size reflective LCD, improve the screen refresh rate, and meet the requirements of multi-color display.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A driving method for a large-size multi-color reflective LCD, the reflective LCD including a plurality of scan lines and a plurality of data lines, and a plurality of pixels driven by the scan lines and the data lines, wherein the scan lines and the data lines are controlled by gate driving and source driving, respectively, comprising the following steps:

[0008] The S1 common electrode applies a first voltage to the pixel, and the data line applies a second voltage to the pixel;

[0009] The S2 common electrode applies a third voltage to the pixel, and the data line applies a second voltage to the pixel;

[0010] When S3 turns on XON, the gate drive sends a signal to turn on all scan lines and all pixels. The source drive sends a signal to input voltage to all data lines. At the same time, the data lines apply a second voltage to all pixels, and the common electrode applies a fourth voltage to all pixels.

[0011] The first voltage, the second voltage, the third voltage, and the fourth voltage are all different. Different voltages mean that the voltages differ in absolute value or polarity.

[0012] Furthermore, both the common electrode and the data line output alternating positive and negative AC voltage signals.

[0013] Furthermore, in step S1, the first voltage and the second voltage have opposite polarities, and the absolute value of the second voltage is greater than the absolute value of the first voltage.

[0014] Further, the charging time in step S1 is 2–8 fs. Further, the charging time in step S1 is 2–6 fs.

[0015] Furthermore, in step S2, the third voltage has the opposite polarity to the second voltage, and the absolute value of the third voltage is equal to the absolute value of the second voltage.

[0016] Further, the charging time in step S2 is 5–10 fs. Further, the charging time in step S2 is 5–8 fs.

[0017] Furthermore, in step S3, the fourth voltage has the opposite polarity to the second voltage, and the absolute value of the fourth voltage is greater than the absolute value of the second voltage.

[0018] Furthermore, the absolute difference between the second voltage and the first voltage is equal to the absolute difference between the fourth voltage and the second voltage.

[0019] Further, the absolute value difference ranges from 1 to 15V. Further, the absolute value difference ranges from 2 to 10V. Further, the absolute value difference ranges from 3 to 10V.

[0020] Furthermore, the charging time in step S3 is the same as the charging time in step S1.

[0021] In summary, this invention provides a driving method for a large-size multi-color reflective LCD, which enables rapid pixel charging on large-size reflective LCDs, improving screen refresh rate and reducing load. Furthermore, because the pixel charging voltage is dynamically adjustable, multi-color display is possible. Attached Figure Description

[0022] Figure 1 Driving timing diagram for a 10.3-inch reflective LCD using existing driving methods;

[0023] Figure 2 A timing diagram of the driving method provided by this invention for a 10.3-inch reflective LCD;

[0024] Figure 3 A timing diagram of the driving method provided by this invention for a 32-inch reflective LCD;

[0025] Figure 4 A timing diagram of the driving method provided by this invention for a 55-inch reflective LCD. Detailed Implementation

[0026] The present invention will be further described in detail below with reference to embodiments. It should be noted that the following embodiments are examples of the present invention and are used only to illustrate the invention, not to limit it. Other combinations and various modifications within the scope of the present invention can be made without departing from the spirit or scope of the invention.

[0027] Example 1

[0028] This embodiment uses a 10.3-inch reflective LCD as the driving object to illustrate the driving method. For a detailed driving timing diagram, please refer to [link / reference needed]. Figure 2 :

[0029] When the screen enters reflective display mode, the gate outputs a 25V voltage to sequentially activate each row of pixels. The common voltage is an alternating positive and negative AC current, with a positive voltage of 10V and a negative voltage of -10V. The data line voltage is an alternating positive and negative AC current, with a positive voltage of 15V and a negative voltage of 15V. The data line voltage has the opposite polarity to the common voltage, and the charging time is 1fs. After charging is complete, the data line is grounded to discharge.

[0030] After discharging, adjust the common voltage to match the data line voltage, i.e., the common voltage positive is 15V and the negative is -15V, but the polarity of the common voltage is opposite to that of the data line voltage. The data line voltage remains unchanged, and the charging time is 5fs. After charging is complete, discharge the data line to ground.

[0031] With XON enabled, the gate voltage remains high at 25V, all scan lines are simultaneously activated, and the data lines charge all pixels concurrently. The common voltage is an alternating positive and negative AC current, with a positive voltage of 20V and a negative voltage of -20V, while the data line voltage remains constant. The common voltage and data line voltage have opposite polarities, requiring at least 1 second to charge the pixels to the clamping voltage required for LC material reflection. Furthermore, because the data line voltage is dynamically adjustable, 4-color or 8-color display can be achieved on a reflective LCD.

[0032] When the screen enters the transition state display, it remains in the reflective state display, all scan lines remain on, the data line is grounded, and the pixel grounding line is discharged to prepare for the screen to switch to the transparent state. The required time is 1fs.

[0033] When the screen enters a transparent display state, the common voltage is positive for the first 10 fs, ranging from 15 to 20V, and negative for the next 10 fs, ranging from -15 to -20V. The data line voltage has the same absolute value as the common voltage, but opposite polarity. At least 10 fs (positive) + 10 fs (negative), a total of 20 fs, are needed to charge the pixel to the voltage required for the LC material. After charging is complete, the data line is grounded, and the pixel discharges to ground.

[0034] According to the driving method of this embodiment, the charging time for a 10.3-inch reflective LCD pixel is 7fs.

[0035] Example 2

[0036] This embodiment uses a 32-inch reflective LCD as the driving object to illustrate the driving method. For a detailed driving timing diagram, please refer to [link / reference needed]. Figure 3 :

[0037] When the screen enters reflective display mode, the gate outputs a 25V voltage to sequentially turn on each row of pixels. The common voltage is an alternating positive and negative AC current, with a positive voltage of 15V and a negative voltage of -15V. The data line voltage is an alternating positive and negative AC current, with a positive voltage of 20V and a negative voltage of 20V. The data line voltage has the opposite polarity to the common voltage. The charging time is 2fs. After charging is completed, the data line is grounded and discharged.

[0038] After discharging, adjust the common voltage to match the data line voltage, i.e., the common voltage positive voltage is 20V and the negative voltage is -20V, but the polarity of the common voltage is opposite to that of the data line voltage. The data line voltage remains unchanged, and the charging time is 5fs. After charging is complete, discharge the data line to ground.

[0039] With XON enabled, the gate voltage remains high at 25V, all scan lines are simultaneously activated, and the data lines charge all pixels concurrently. The common voltage is an alternating positive and negative AC current, with a positive voltage of 25V and a negative voltage of -25V, while the data line voltage remains constant. The common voltage and data line voltage have opposite polarities, requiring at least 2 seconds to charge the pixels to the voltage required for LC material reflection. Furthermore, because the data line voltage is dynamically adjustable, 4-color or 8-color display can be achieved on a reflective LCD.

[0040] When the screen enters the transition state display, it remains in the reflective state display, all scan lines remain on, the data line is grounded, and the pixel grounding line is discharged to prepare for the screen to switch to the transparent state. The required time is 1fs.

[0041] When the screen enters a transparent display state, the common voltage is positive for the first 15 seconds, ranging from 10 to 25V, and negative for the next 15 seconds, ranging from -25V to -10V. The data line voltage has the same absolute value as the common voltage, but opposite polarity. At least 30 seconds (15 seconds positive + 15 seconds negative) are needed to charge the pixel to the voltage required for the LC material. After charging is complete, the data line is grounded, and the pixel discharges to ground.

[0042] According to the driving method of this embodiment, the charging time for a 32-inch reflective LCD pixel is 9 fs.

[0043] Example 3

[0044] This embodiment uses a 55-inch reflective LCD as the driving object to illustrate the driving method. For a detailed driving timing diagram, please refer to [link / reference needed]. Figure 4 :

[0045] When the screen enters reflective display mode, the gate outputs a 25V voltage to sequentially activate each row of pixels. The common voltage is an alternating positive and negative AC current, with a positive voltage of 5V and a negative voltage of -5V. The data line voltage is an alternating positive and negative AC current, with a positive voltage of 20V and a negative voltage of -20V. The data line voltage has the opposite polarity to the common voltage, and the charging time is 8 fs. After charging is complete, the data line is grounded to discharge.

[0046] After discharging, adjust the common voltage to match the data line voltage, i.e., the common voltage positive voltage is 20V and the negative voltage is -20V, but the polarity of the common voltage is opposite to that of the data line voltage. The data line voltage remains unchanged, and the charging time is 5fs. After charging is complete, discharge the data line to ground.

[0047] With XON enabled, the gate voltage remains high at 25V, all scan lines are simultaneously activated, and the data lines charge all pixels concurrently. The common voltage is an alternating positive and negative AC current, with a positive voltage of 35V and a negative voltage of -35V, while the data line voltage remains constant. The common voltage and data line voltage have opposite polarities, requiring at least 8 seconds to charge the pixels to the clamping voltage needed for LC material reflection. Furthermore, because the data line voltage is dynamically adjustable, 4-color or 8-color display can be achieved on a reflective LCD.

[0048] When the screen enters the transition state display, it remains in the reflective state display, all scan lines remain on, the data line is grounded, and the pixel grounding line is discharged to prepare for the screen to switch to the transparent state. The required time is 1fs.

[0049] When the screen enters a transparent display state, the common voltage is positive for the first 80 fs, ranging from 5 to 50V, and negative for the next 80 fs, ranging from -5 to -50V. The data line voltage has the same absolute value as the common voltage, but opposite polarity. At least 80 fs (positive) + 80 fs (negative), a total of 182 fs, are needed to charge the pixel to the voltage required for the LC material. After charging is complete, the data line is grounded, and the pixel discharges to ground.

[0050] According to the driving method of this embodiment, the charging time for a 55-inch reflective LCD pixel is 21 fs.

[0051] In Example 1, the time required for a 10.3-inch reflective LCD to complete pixel charging is 7 fs; in Example 2, the time required for a 32-inch reflective LCD to complete pixel charging is 9 fs. Both are significantly shorter than the pixel charging time (20 fs) required for a 10.3-inch reflective LCD using the existing driving method. Furthermore, in Example 3, the time required for a 55-inch reflective LCD to complete pixel charging is 21 fs, almost the same as the pixel charging time required for a 10.3-inch reflective LCD using the existing driving method. Therefore, the above examples demonstrate that the pixel charging time of reflective LCDs using this driving method is significantly shortened, which can improve the technical problems of high load and low frame rate in large-size reflective LCDs. Moreover, since the data line charging voltage is dynamically adjustable, multi-color display can be achieved. Thus, this invention can significantly improve the display effect of large-size reflective LCDs.

[0052] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A driving method for a large-size multi-color reflective LCD, the reflective LCD comprising a plurality of scan lines and a plurality of data lines, and a plurality of pixels driven by the scan lines and the data lines, wherein the scan lines and the data lines are controlled by gate driving and source driving, respectively, characterized in that, The method comprises the following steps: S1: the common electrode applies a first voltage to the pixel, and the data line applies a second voltage to the pixel; S2: the common electrode applies a third voltage to the pixel, and the data line applies the second voltage to the pixel; S3: XON is opened, the gate drive sends a signal to open all the scanning lines, all the pixels are opened, the source drive sends a signal to input the voltage to all the data lines, the data line simultaneously applies the second voltage to all the pixels, and the common electrode simultaneously applies a fourth voltage to all the pixels; The first voltage, the second voltage, the third voltage and the fourth voltage are different from each other; The first voltage and the second voltage are opposite in polarity, the absolute value of the second voltage is greater than that of the first voltage; the third voltage and the second voltage are opposite in polarity, the absolute value of the third voltage is equal to that of the second voltage; and the fourth voltage and the second voltage are opposite in polarity, the absolute value of the fourth voltage is greater than that of the second voltage.

2. The driving method of a large-sized multi-color reflective LCD according to claim 1, wherein The common electrode and the data line both output alternating-current voltages.

3. The driving method of a large-sized multi-color reflective LCD according to claim 1, wherein The charging time of step S1 is 2-8fs.

4. The driving method of a large-sized multi-color reflective LCD according to claim 1, wherein The charging time of step S2 is 5-10fs.

5. The driving method of a large-sized multi-color reflective LCD according to claim 1, wherein The absolute value difference between the second voltage and the first voltage is equal to the absolute value difference between the fourth voltage and the second voltage.

6. The driving method of a large-sized multi-color reflective LCD according to claim 5, wherein The absolute value difference ranges from 1 to 15V.

7. The driving method of a large-sized multi-color reflective LCD according to claim 1, wherein The charging time of step S3 is the same as that of step S1.

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