TWI754358B - Display device and control method - Google Patents

Abstract

A display device including a first panel and a second panel is disclosed. The second panel is located below the first panel. A gamma value of the first panel is higher than a gamma value of the second panel, and the gamma curve of the first panel is discontinuous.

Description

Display device and control method

The contents of the embodiments described in the present disclosure relate to a display device and a control method, and in particular, to a display device and a control method of a double-layer panel.

The dual-layer display is a double-layered design where two screens are overlapped, the lower layer uses black and white units, and the upper layer uses a double-layer design of color units. With a high-contrast image processing algorithm, it can make the bright part of the image brighter and the dark part darker to achieve ultra-high contrast. . Due to the high contrast characteristics, double-layer displays can be applied to TVs, but also to automotive instrument displays and medical displays. In order to reduce costs, lower-level displays can use twisted nematic panels, but twisted nematic panels produce large viewing angles. The problem of color gradation reversal. After matching with the upper panel, the display color will be wrong or even reversed at a large viewing angle.

Some embodiments of the present disclosure relate to a display device. The display device includes a first panel and a second panel. The second panel is located below the first panel. The gamma value of the first panel is higher than the gamma value of the second panel, and the gamma curve of the first panel is discontinuous.

Some embodiments of the present disclosure relate to a control method, which is applicable to a display device including a first panel and a second panel, wherein the second panel is located under the first panel, and the control method includes the following steps: adjusting by a processor to make the first panel The gamma value of one panel is higher than the gamma value of the second panel, wherein the gamma value of the first panel is discontinuous at the first threshold value; and is adjusted by the processor when the input signal input to the second panel is input When the grayscale value is lower than the second threshold value, the processor applies the first matrix and the first offset to the input signal; when the input grayscale value is not lower than the second threshold value, the processor applies the second matrix and the second offset to the input signal. Move to the input signal, where the second threshold corresponds to the first threshold.

To sum up, the display device and the control method of the present disclosure can achieve no gradation inversion in either the positive viewing angle gradation or the large viewing angle gradation.

As used herein, the term "coupled" may also refer to "electrically coupled," and the term "connected" may also refer to "electrically connected." "Coupled" and "connected" may also refer to two or more elements cooperating or interacting with each other.

See Figure 1. FIG. 1 is a schematic diagram of a display device 100 according to some embodiments of the present disclosure.

Taking the example of FIG. 1 as an example, the display device 100 includes panels 110A and 110B and a processor 130 . In connection, the processor 130 is coupled to the panel 110A and the panel 110B. Panel 110B is located below panel 110A. In some embodiments, the resolution of panel 110B is smaller than that of panel 110A. The above-mentioned configuration of the display device 100 is for illustrative purposes only, and the embodiments of the present application are not limited thereto.

In some embodiments, the gamma value of the panel 110A is higher than a gamma value of the panel 110B, and the gamma curve of the panel 110A is discontinuous.

See Figure 2. FIG. 2 is a schematic diagram of a gamma curve 200 according to some embodiments of the present disclosure. The gamma curve 200 shown in FIG. 2 is suitable for the panel 110A as depicted in FIG. 1 . It can be seen from FIG. 2 that the gamma curve 200 includes discontinuities, such as the places marked by dotted circles.

As shown in FIG. 2 , the gray-scale section lower than the threshold value TH1 corresponds to the sub-gamma value Γ1 , and the gray-scale section not lower than the threshold value TH1 corresponds to the sub-gamma value Γ2 . In some embodiments, the sub-gamma value Γ1 is lower than the sub-gamma value Γ2.

In some embodiments, when images are to be input to the panels 110A and 110B, the input signal input to the panel 110A is directly output to the panel 110A, and the input signal input to the panel 110B is adjusted by the processor 130 and then output to the panel 110B.

Specifically, the input signal input to the panel 110B will first undergo gray scale conversion and signal amplification. Then, when the input grayscale value of the input signal input to the panel 110B is lower than the threshold value TH2, the processor 130 applies the first matrix and the first offset to the input signal; when the input grayscale value is not lower than the threshold value TH2 , the processor applies the second matrix and the second offset to the input signal. In some embodiments, the first matrix is smaller than the second matrix.

Next, the processor 130 performs a division operation, the larger the division value, the darker the color. After the division operation, the processor 130 performs inverse gamma conversion, and then outputs the signal to the panel 110B. In some embodiments, when the input grayscale value is lower than the threshold value TH2, the processor 130 reduces the division value when performing the dividing operation; when the input grayscale value is not lower than the threshold value TH2, the processor 130 increases The division value when performing the division operation.

In some embodiments, the threshold value TH1 and the threshold value TH2 correspond to and are close to each other. In some embodiments, the threshold value TH1 and the threshold value TH2 are set by the processor 130 .

See Figure 3. FIG. 3 is a schematic diagram of a gamma curve 300 according to some embodiments of the present disclosure. The gamma curve 300 shown in FIG. 3 is suitable for the panel 110B as depicted in FIG. 1 . In some embodiments, the gamma value in FIG. 3 is 0.1, but the embodiments of the present application are not limited thereto.

In some embodiments, the gamma value of panel 110A is greater than 2, and the gamma value of panel 110B is less than 0.2.

In some embodiments, the display device 100 shown in FIG. 1 further includes a gate driving circuit (not shown), a source driving circuit (not shown), etc., and the gate driving circuit and the source driving circuit are both. are coupled to panels 110A and 110B, respectively.

See Figure 4. FIG. 4 is a flowchart of a control method 400 according to some embodiments of the present disclosure. The control method 400 includes steps S410 and S430. In some embodiments, the control method 400 is applied to the display device 100 of FIG. 1 , but the present disclosure is not limited thereto. For easy understanding, the control method 400 will be discussed in conjunction with the display device 100 of FIG. 1 .

In step S410, the processor adjusts the gamma value of the first panel to be higher than the gamma value of the second panel, wherein the gamma value of the first panel is discontinuous at the first threshold value.

For example, the processor 130 in FIG. 1 adjusts the gamma value of the panel 110A to be higher than the gamma value of the panel 110B, wherein the gamma value of the panel 110A is discontinuous at the threshold value TH1.

In step S430, the processor performs adjustment. When the input grayscale value of the input signal input to the second panel is lower than the second threshold value, the processor applies the first matrix and the first offset to the input signal; When the gray scale value is not lower than the second threshold value, the processor applies the second matrix and the second offset to the input signal, wherein the second threshold value corresponds to the first threshold value.

For example, the processor 130 in FIG. 1 performs adjustment. When the input grayscale value of the input signal input to the panel 110B is lower than the threshold value TH2, the processor 130 applies the first matrix and the first offset to the input signal. ; When the input grayscale value is not lower than the threshold value TH2, the processor 130 applies the second matrix and the second offset to the input signal. The threshold value TH2 corresponds to the threshold value TH1.

To sum up, the display device and the control method of the present disclosure can adjust the image through the algorithm and adjust the gamma value of the panel, which can avoid the display color error at different viewing angles after the lower panel is matched with the upper panel, and ensure that regardless of the front viewing angle There is no tone inversion for either tone or large viewing angle tone.

In some embodiments, the processor 130 may be a central processing unit (Central Processing Unit, CPU), a control unit (control unit), a microprocessor (micro processor) or other hardware components that can execute instructions. Wherein, each module of the processing element can be implemented as code, and the code is stored in the storage element. Therefore, after the processing element reads and executes the code in the storage element, the corresponding functions of each module are provided.

In some embodiments, the panels 110A, 110B may be display panels having the function of displaying images or circuits having the same or similar functions.

Although the present disclosure has been disclosed as above in embodiments, it is not intended to limit the present disclosure. Anyone with ordinary knowledge in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure. The scope of protection shall be determined by the scope of the appended patent application.

100: Display device 110A, 110B: Panel 130: Processor 200: Gamma Curve 300: Gamma Curve Γ1, Γ2: detection circuit 400: Control Method S410, S430: Steps

In order to make the above and other objects, features, advantages and embodiments of the present disclosure more clearly understood, the accompanying drawings are described as follows: FIG. 1 is a schematic diagram of a display device according to some embodiments of the present disclosure; FIG. 2 is a schematic diagram of a gamma curve according to some embodiments of the present disclosure; FIG. 3 is a schematic diagram of a gamma curve according to some embodiments of the present disclosure; and FIG. 4 is a flowchart of a control method according to some embodiments of the present disclosure.

100: Display device

110A, 110B: Panel

130: Processor

Claims (9)

A display device comprising: a first panel; a second panel located under the first panel, wherein a gamma value of the first panel is higher than a gamma value of the second panel, and the first panel A gamma curve of the panel is discontinuous at a first threshold value; and a processor is coupled to the second panel, wherein when an input grayscale value of an input signal input to the second panel is lower than a first threshold When there are two thresholds, the processor applies a first matrix and a first shift to the input signal; when the input grayscale value is not lower than the second threshold, the processor applies A second matrix and a second offset are applied to the input signal, wherein the second threshold corresponds to the first threshold. The display device of claim 1, wherein the gamma curve of the first panel corresponds to a first sub-gamma value in a first gray-scale segment, and corresponds to a first sub-gamma value in a second gray-scale segment Binary Gamma. The display device of claim 2, wherein the first grayscale segment is lower than the first threshold value, the second grayscale segment is not lower than the first threshold value, and the first sub-gamma value less than the second sub-gamma value. The display device of claim 1, wherein the first matrix is smaller than the second matrix. The display device of claim 1, wherein the processor is further configured to set the first threshold value and the second threshold value. The display device of claim 1, wherein when the input grayscale value is lower than the second threshold value, the processor is further configured to decrease a division value; when the input grayscale value is not lower than the second threshold value When the threshold value is reached, the processor is further used to increase the division value. The display device of claim 1, wherein the gamma value of the first panel is greater than 2, and the gamma value of the second panel is less than 0.2. The display device of claim 1, wherein a resolution of the second panel is smaller than a resolution of the first panel. A control method, suitable for a display device including a first panel and a second panel, and the second panel is located under the first panel, the control method comprising: adjusting by a processor to make the first panel A gamma value of the second panel is higher than a gamma value of the second panel, wherein the gamma value of the first panel is discontinuous at a first threshold value; and adjusted by a processor, when input to the second panel When an input grayscale value of an input signal of the panel is lower than a second threshold value, the processor applies a first matrix (matrix) and a first shift (shift) to the input signal; when the input grayscale value is When the value is not lower than the second threshold, the processor applies A second matrix and a second offset are applied to the input signal, wherein the second threshold corresponds to the first threshold.

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