A driving method for a color display screen

Abstract

This application relates to a driving method for a color display screen, which includes RED cholesteric liquid crystal, GREEN cholesteric liquid crystal, and BLUE cholesteric liquid crystal. The method includes the following steps: applying a pair of first low-frequency high-voltage positive and negative pulses with the same frequency, the same voltage amplitude, and opposite phase to the strip electrodes of the row electrode layer and the column electrode layer of the R / G / B cholesteric liquid crystal, respectively, for a first preset time, and then stopping the application of the first low-frequency high-voltage positive and negative pulses; simultaneously applying second low-frequency high-voltage positive and negative pulses to the strip electrodes of the row electrode layer of the R / G / B cholesteric liquid crystal, and applying second low-frequency high-voltage positive and negative pulses with the same frequency, the same voltage amplitude, and the same or different phase to the strip electrodes of the scanning drive column and other column electrodes that are not scanned. This application superimposes three monochrome screens (Red, Green, and Blue) and drives them using specific waveforms, resulting in a simple structure and a relatively easy-to-implement driving method.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a driving method for a color display screen. Background Technology

[0002] In the field of liquid crystal displays (LCDs), cholesteric liquid crystals are one of the mainstream materials, widely used in electronic products such as LCD TVs, computer monitors, and smartphone screens. They play an important role in improving display resolution, contrast, and color performance. Most existing cholesteric liquid crystal displays are monochrome displays, while three-color displays have a more complex structure and face many challenges in driving them.

[0003] Chinese Patent CN107728399A discloses a color electronic paper display screen made using cholesteric liquid crystal, comprising three RGB glass cells: an "R" layer liquid crystal cell A, a "G" layer liquid crystal cell B, and a "B" layer liquid crystal cell C. An OC2 double-sided adhesive film is used between the "B" layer liquid crystal cell C and the "G" layer liquid crystal cell B, and an OC1 double-sided adhesive film is used between the "G" layer liquid crystal cell B and the "R" layer liquid crystal cell A. The "R" layer liquid crystal display cell includes an upper ITO glass, a lower ITO glass, a frame adhesive, and a gasket. The upper and lower ITO glass are fixed by the frame adhesive and the gasket. Below the upper ITO glass is an upper ITO layer, and above the lower ITO glass is a lower ITO layer. Between the upper and lower ITO layers is a 650 nm cholesteric liquid crystal. However, in practical applications, this solution has the problem of requiring a large voltage and incurring high costs when driving a three-color display screen. Summary of the Invention

[0004] The purpose of this application is to provide a driving method for a color display screen, which solves the problem of inconvenience in driving current three-color cholesteric liquid crystal displays.

[0005] The technical solution of the present invention is: a driving method for a color display screen, the display screen comprising an R-layer glass liquid crystal cell, a G-layer glass liquid crystal cell, and a B-layer glass liquid crystal cell, wherein the R-layer glass liquid crystal cell comprises RED cholesteric liquid crystal, the G-layer glass liquid crystal cell comprises GREEN cholesteric liquid crystal, the B-layer glass liquid crystal cell comprises BLUE cholesteric liquid crystal, and an OC adhesive is used between the R-layer glass liquid crystal cell and the G-layer glass liquid crystal cell, and an OC adhesive is used between the G-layer glass liquid crystal cell and the B-layer glass liquid crystal cell;

[0006] The upper layer of the RED cholesteric liquid crystal consists of an upper ITO layer and an upper glass layer, and the lower layer of the RED cholesteric liquid crystal consists of a lower ITO layer and a lower glass layer. The RED cholesteric liquid crystal, GREEN cholesteric liquid crystal, and BLUE cholesteric liquid crystal each have strip electrodes in the row electrode layer and strip electrodes in the column electrode layer. The strip electrodes in the row electrode layer and the strip electrodes in the column electrode layer are connected to the driver through conductive lines.

[0007] The method includes the following steps:

[0008] Step 1. Apply a pair of first low-frequency high-voltage positive and negative pulses with the same frequency, the same voltage amplitude, and opposite phase to the strip electrodes of the row electrode and column electrode layer of the RED cholesteric liquid crystal, GREEN cholesteric liquid crystal, and BLUE cholesteric liquid crystal, respectively, for a first preset time, and then stop applying the first low-frequency high-voltage positive and negative pulses.

[0009] Step 2. While applying a second low-frequency high-voltage positive and negative pulse to the strip electrodes of the row electrode layers of the RED cholesteric liquid crystal, GREEN cholesteric liquid crystal, and BLUE cholesteric liquid crystal, apply a second low-frequency high-voltage positive and negative pulse with the same frequency, voltage amplitude, and phase or different from the second low-frequency high-voltage positive and negative pulse to the strip electrodes of the scanning drive column and the other column electrodes of the non-scanning drive column, respectively.

[0010] Preferably, step 2 specifically comprises:

[0011] Step 21. After applying a second low-frequency high-voltage positive and negative pulse with the same frequency, voltage amplitude, and phase to the strip electrodes of the row electrode layer and the strip electrodes of the scanning drive column of the RED cholesteric liquid crystal, GREEN cholesteric liquid crystal, and BLUE cholesteric liquid crystal for a second preset time, stop applying the second low-frequency high-voltage positive and negative pulse.

[0012] Step 22. After applying a second low-frequency high-voltage positive and negative pulse with the same frequency, the same voltage amplitude, and opposite phase to the other column electrodes that are not scanned, stop applying the second low-frequency high-voltage positive and negative pulse after a second preset time.

[0013] Step 23. Repeat steps 21 and 22 at least once.

[0014] Preferably, the frequency of the first low-frequency high-voltage positive and negative pulses is greater than or equal to 100Hz and less than or equal to 1000Hz, the amplitude of the low-frequency high-voltage positive and negative pulses is greater than or equal to 20V and less than or equal to 40V, the number of pulse pairs for loading the first low-frequency high-voltage positive and negative pulses is greater than or equal to 1 and less than or equal to 20, and the time for stopping loading the first low-frequency high-voltage positive and negative pulses is greater than or equal to 10ms and less than or equal to 1000ms.

[0015] Preferably, the frequency of the second low-frequency high-voltage positive and negative pulses is greater than or equal to 500Hz and less than or equal to 4000Hz, the amplitude of the low-frequency high-voltage positive and negative pulses is greater than or equal to 10V and less than or equal to 18V, the number of pulse pairs for loading the second low-frequency high-voltage positive and negative pulses is greater than or equal to 1 and less than or equal to 20, and the time for stopping loading the second low-frequency high-voltage positive and negative pulses is greater than or equal to 1ms and less than or equal to 10ms.

[0016] Preferably, the driver includes a control unit, an interface unit, a temperature detection unit, a pressure detection unit, a graphics storage unit, a voltage generation unit, a waveform generation unit, and a timer.

[0017] Compared with existing technologies, the advantages of this application are: This invention mainly involves superimposing Red, Green, and Blue monochrome screens on a monochrome cholesteric liquid crystal display screen, and then driving it using a driver that generates a specific waveform. This not only simplifies the STN structure but also makes the driving method relatively easy to implement. Attached Figure Description

[0018] The present application will be further described below with reference to the accompanying drawings and embodiments:

[0019] Figure 1 This is a schematic diagram of the structure of a color display screen, which is a driving method for a color display screen according to this application.

[0020] Figure 2 This is a schematic diagram of the row electrode layer and column electrode layer of a driving method for a color display screen according to this application;

[0021] Figure 3 This is a schematic diagram of the driver structure of a color display screen driving method according to this application;

[0022] Figure 4 This is a schematic diagram of the image clearing process of a driving method for a color display screen according to this application;

[0023] Figure 5 This is a schematic diagram of the image clearing pulse waveform for a color display screen driving method according to this application;

[0024] Figure 6 This is a schematic diagram illustrating the graphic display process of a driving method for a color display screen according to this application;

[0025] Figure 7 This is a schematic diagram of a pulse waveform displayed by a driving method for a color display screen according to this application.

[0026] in:

[0027] 1. Upper glass, 2. Upper ITO layer, 3. RED cholesteric liquid crystal, 4. Lower ITO layer, 5. Lower glass, 6. OC adhesive, 7. GREEN cholesteric liquid crystal, 8. BLUE cholesteric liquid crystal, 9. Conductive wire, 10. Driver, 11. Strip electrode of row electrode layer, 12. Strip electrode of column electrode layer. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely one embodiment of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0029] The term "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of this application. In the description of the embodiments of this application, it should be understood that the terms "first," "second," and "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," and "third," etc., may explicitly or implicitly include one or more of that feature. Furthermore, the terms "first," "second," and "third," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Moreover, the terms "comprising" and "being," and any variations thereof, are intended to cover non-exclusive inclusion.

[0030] like Figure 1-2 As shown, this embodiment provides a driving method for a color display screen, which includes an R-layer glass liquid crystal cell, a G-layer glass liquid crystal cell, and a B-layer glass liquid crystal cell. The R-layer glass liquid crystal cell includes RED cholesteric liquid crystal 3, the G-layer glass liquid crystal cell includes GREEN cholesteric liquid crystal 7, and the B-layer glass liquid crystal cell includes BLUE cholesteric liquid crystal 8. An OC adhesive (6) is used between the R-layer glass liquid crystal cell and the G-layer glass liquid crystal cell, and an OC adhesive (6) is used between the G-layer glass liquid crystal cell and the B-layer glass liquid crystal cell.

[0031] The upper layer of the RED cholesteric liquid crystal 3 consists of an upper ITO layer 2 and an upper glass layer 1, and the lower layer of the RED cholesteric liquid crystal 3 consists of a lower ITO layer 4 and a lower glass layer 5. The RED cholesteric liquid crystal 3, GREEN cholesteric liquid crystal 7, and BLUE cholesteric liquid crystal 8 each have strip electrodes 11 of row electrode layers and strip electrodes 12 of column electrode layers. The strip electrodes 11 of row electrode layers and strip electrodes 12 of column electrode layers are connected to a driver 10 through conductive lines 9. Each display layer is an STN structure with the same resolution. It should be noted that cholesteric liquid crystal displays are well-known electronic display devices in the art, so their specific structure will not be described in detail here.

[0032] like Figure 3 As shown, in this embodiment, the driver 10 includes a control unit, an interface unit, a temperature detection unit, a pressure detection unit, a graphics storage unit, a voltage generation unit, a waveform generation unit, and a timer.

[0033] like Figure 4 As shown, in this embodiment, the first step in driving the color display screen is to clear the image on the screen. This clearing process requires selecting all row electrodes and all column electrodes in the R / G / B arrays before outputting the waveform, as shown below. Figure 5 As shown, the waveform output method includes: applying a pair of first low-frequency high-voltage positive and negative pulses with the same frequency, the same voltage amplitude, and opposite phase to the strip electrodes of the row electrode and column electrode layer of the RED cholesteric liquid crystal 3, GREEN cholesteric liquid crystal 7, and BLUE cholesteric liquid crystal 8 respectively for a first preset time, and then stopping the application of the first low-frequency high-voltage positive and negative pulses. At this time, the strip electrodes 11 of the row electrode layer and the strip electrodes 12 of the column electrode layer are de-energized.

[0034] Then, the first low-frequency high-voltage positive and negative pulses are repeatedly applied to the strip electrodes of the row electrodes and column electrode layers of the RED cholesteric liquid crystal 3, GREEN cholesteric liquid crystal 7, and BLUE cholesteric liquid crystal 8 at least twice, and in practical applications, up to 20 times. The interval between each pulse is greater than or equal to 10ms and less than or equal to 1000ms. The frequency of the first low-frequency high-voltage positive and negative pulses is greater than or equal to 100Hz and less than or equal to 1000Hz, and the amplitude of the low-frequency high-voltage positive and negative pulses is greater than or equal to 20V and less than or equal to 40V.

[0035] like Figure 6 As shown, in this embodiment, the process of driving the color display screen to display graphics includes sequentially reading and selecting all the strip electrodes 11 of the row electrode layers in R / G / B, identifying the state corresponding to the strip electrodes 12 of all the column electrode layers in R / G / B, and then outputting a waveform, as shown in the figure. Figure 7 As shown, the waveform output methods include:

[0036] While applying a second low-frequency high-voltage positive and negative pulse to the strip electrodes of the row electrode layer of the RED cholesteric liquid crystal, GREEN cholesteric liquid crystal, and BLUE cholesteric liquid crystal, a second low-frequency high-voltage positive and negative pulse with the same frequency, voltage amplitude, and phase or different from the second low-frequency high-voltage positive and negative pulse is applied to the strip electrodes of the scanning drive column and the other column electrodes that are not scan driven.

[0037] Step 2 specifically involves:

[0038] Step 21. After applying a second low-frequency high-voltage positive and negative pulse with the same frequency, voltage amplitude, and phase to the strip electrodes of the row electrode layer and the strip electrodes of the scanning drive column of the RED cholesteric liquid crystal, GREEN cholesteric liquid crystal, and BLUE cholesteric liquid crystal for a second preset time, stop applying the second low-frequency high-voltage positive and negative pulse.

[0039] Step 22. After applying a second low-frequency high-voltage positive and negative pulse with the same frequency, the same voltage amplitude, and opposite phase to the other column electrodes that are not scanned, stop applying the second low-frequency high-voltage positive and negative pulse after a second preset time.

[0040] Step 23. Repeat steps 21 and 22 at least once, and in practice, up to 20 times. The interval between repetitions should be greater than or equal to 1 ms and less than or equal to 10 ms.

[0041] The frequency of the second low-frequency high-voltage positive and negative pulses is greater than or equal to 500Hz and less than or equal to 4000Hz, and the amplitude of the low-frequency high-voltage positive and negative pulses is greater than or equal to 10V and less than or equal to 18V.

[0042] The above embodiments are merely illustrative of the technical concept and features of this application, intended to enable those skilled in the art to understand the content of this application and implement it accordingly, and should not be construed as limiting the scope of protection of this application. It is obvious to those skilled in the art that this application is not limited to the details of the above exemplary embodiments, and that this application can be implemented in other specific forms without departing from the spirit or essential characteristics of this application. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this application is defined by the appended claims rather than the foregoing description, and thus all variations falling within the meaning and scope of the equivalents of the claims are intended to be included within this application.

Claims

1. A driving method for a color display screen, characterized in that, The display screen includes an R-layer glass liquid crystal cell, a G-layer glass liquid crystal cell, and a B-layer glass liquid crystal cell. The R-layer glass liquid crystal cell includes RED cholesteric liquid crystal (3), the G-layer glass liquid crystal cell includes GREEN cholesteric liquid crystal (7), and the B-layer glass liquid crystal cell includes BLUE cholesteric liquid crystal (8). The R-layer glass liquid crystal cell and the G-layer glass liquid crystal cell, as well as the G-layer glass liquid crystal cell and the B-layer glass liquid crystal cell, are bonded with OC adhesive (6). The upper layer of the RED cholesteric liquid crystal (3) consists of an upper ITO layer (2) and an upper glass layer (1), and the lower layer of the RED cholesteric liquid crystal (3) consists of a lower ITO layer (4) and a lower glass layer (5). The RED cholesteric liquid crystal (3), GREEN cholesteric liquid crystal (7) and BLUE cholesteric liquid crystal (8) are respectively provided with strip electrodes (11) of row electrode layer and strip electrodes (12) of column electrode layer. The strip electrodes (11) of row electrode layer and strip electrodes (12) of column electrode layer are connected to the driver (10) through conductive lines (9). The method includes the following steps: Step 1. Apply a pair of first low-frequency high-voltage positive and negative pulses with the same frequency, the same voltage amplitude, and opposite phase to the strip electrodes of the row electrode and column electrode layer of the RED cholesteric liquid crystal (3), GREEN cholesteric liquid crystal (7), and BLUE cholesteric liquid crystal (8) for a first preset time, and then stop applying the first low-frequency high-voltage positive and negative pulses. Step 2. After applying a second low-frequency high-voltage positive and negative pulse with the same frequency, voltage amplitude, and phase to the strip electrodes of the row electrode layer and the strip electrodes of the scanning drive column of the RED cholesteric liquid crystal (3), GREEN cholesteric liquid crystal (7), and BLUE cholesteric liquid crystal (8) for a second preset time, stop applying the second low-frequency high-voltage positive and negative pulse; After applying second low-frequency high-voltage positive and negative pulses with the same frequency, the same voltage amplitude, and opposite phase to other column electrodes that are not scanned for a second preset time, the application of the second low-frequency high-voltage positive and negative pulses is stopped; Repeat steps 21 and 22 at least once.

2. The driving method for a color display screen according to claim 1, characterized in that, The frequency of the first low-frequency high-voltage positive and negative pulses is greater than or equal to 100Hz and less than or equal to 1000Hz, the amplitude of the low-frequency high-voltage positive and negative pulses is greater than or equal to 20V and less than or equal to 40V, the number of pulse pairs for loading the first low-frequency high-voltage positive and negative pulses is greater than or equal to 1 and less than or equal to 20, and the time for stopping loading the first low-frequency high-voltage positive and negative pulses is greater than or equal to 10ms and less than or equal to 1000ms.

3. The driving method for a color display screen according to claim 2, characterized in that, The frequency of the second low-frequency high-voltage positive and negative pulses is greater than or equal to 500Hz and less than or equal to 4000Hz, the amplitude of the low-frequency high-voltage positive and negative pulses is greater than or equal to 10V and less than or equal to 18V, the number of pulse pairs for loading the second low-frequency high-voltage positive and negative pulses is greater than or equal to 1 and less than or equal to 20, and the time for stopping loading the second low-frequency high-voltage positive and negative pulses is greater than or equal to 1ms and less than or equal to 10ms.

4. The driving method for a color display screen according to claim 3, characterized in that, The driver (10) includes a control unit, an interface unit, a temperature detection unit, a pressure detection unit, a graphics storage unit, a voltage generation unit, a waveform generation unit, and a timer.

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