KR-20260064806-A - DISPLAY DEVICE, METHOD OF OPERATING A DISPLAY DEVICE, AND ELECTRONIC DEVICE

Abstract

The display device includes a display panel comprising a plurality of pixels, and a panel driver that receives image data and a display brightness value and drives the display panel based on the image data and the display brightness value. The panel driver determines whether the image data represents a low-gradation image, and if the image data does not represent a low-gradation image, performs a smooth dimming operation that gradually changes the brightness of the display panel to a brightness corresponding to the display brightness value over a plurality of frame intervals, and if the image data represents a low-gradation image, does not perform a smooth dimming operation. Accordingly, when displaying a normal image after displaying a low-gradation image, or when the mode of the display device is switched, the change in brightness caused by the smooth dimming operation may be prevented from being visible.

Inventors

• 하태석
• 김종운

Assignees

• 삼성디스플레이 주식회사

Dates

Publication Date

20260508

Application Date

20241029

Claims (20)

1. A display panel including a plurality of pixels; and It includes a panel driving unit that receives image data and a display brightness value, and drives the display panel based on the image data and the display brightness value. The above panel driving unit is, Determining whether the above image data represents a low-gradation image, and If the above image data does not represent the low-gradation image, a smooth dimming operation is performed to gradually change the brightness of the display panel to a brightness corresponding to the display brightness value over multiple frame intervals. A display device characterized by not performing the smooth dimming operation when the above image data represents the low-gradation image.
2. In claim 1, the panel driving unit is, A display device characterized by changing the brightness of the display panel to a brightness corresponding to the display brightness value in the frame interval where the display brightness value is received, when the above image data represents the low-gradation image.
3. In claim 2, the panel driving unit is, If the above image data does not represent the low-gradation image, the gamma voltages are gradually changed over the plurality of frame intervals to perform the smooth dimming operation, and A display device characterized by changing the gamma voltages in the frame interval where the display brightness value is received, when the above image data represents the low-gradation image.
4. A display device according to claim 1, characterized in that the low-gradation image is an image of a reference gradation or lower.
5. A display device according to claim 4, characterized in that the reference grayscale has a predetermined fixed value.
6. A display device according to claim 4, characterized in that the reference gradation can be set by a gradation option.
7. In claim 1, the panel driving unit is, Count the number of pixels among the plurality of pixels in which the image data represents a grayscale lower than or equal to the reference grayscale, and Comparing the number of pixels counted above with the reference number, A display device characterized by determining that the image data represents the low-gradation image when the number of pixels counted above is greater than or equal to the reference number.
8. A display device according to claim 7, characterized in that the reference grayscale and the reference number have predetermined fixed values.
9. In claim 7, the above reference gradation can be set by a gradation option, and A display device characterized in that the above-mentioned standard number can be set by a number option.
10. In claim 1, the panel driving unit is, A scan driver that provides scan signals to the plurality of pixels above; Gamma voltage generator that generates gamma voltages; A data driver that provides data voltages to the plurality of pixels based on the above gamma voltages; and It includes a controller that controls the scan driver, the gamma voltage generator, and the data driver, and The above controller is, A low-gradation image determination block that determines whether the above image data represents the low-gradation image; and A display device characterized by including a dimming block that controls the gamma voltage generator to adjust the gamma voltages according to the display brightness value and selectively performs the smooth dimming operation depending on whether the image data represents the low-gradation image.
11. In claim 10, the low-gradation image judgment block is, Count the number of pixels among the plurality of pixels in which the image data represents a grayscale lower than or equal to the reference grayscale, and Comparing the number of pixels counted above with the reference number, A display device characterized by determining that the image data represents the low-gradation image when the number of pixels counted above is greater than or equal to the reference number.
12. In Article 11, The above reference grayscale is 0-grayscale or 1-grayscale, and A display device characterized in that the above reference number is the total number of the above plurality of pixels.
13. In claim 10, the controller is, It further includes an option storage block that stores gradation options and count options, The above low-gradation image judgment block is, Count the number of pixels among the plurality of pixels in which the image data represents a gradation lower than or equal to the reference gradation indicated by the gradation option, and Comparing the number of pixels counted above with the reference number indicated by the count option, A display device characterized by determining that the image data represents the low-gradation image when the number of pixels counted above is greater than or equal to the reference number.
14. In claim 10, the dimming block is, If it is determined by the low-gradation image determination block that the image data does not represent the low-gradation image, the gamma voltage generator is controlled to gradually change the gamma voltages over the plurality of frame intervals, and A display device characterized by controlling the gamma voltage generator to change the gamma voltages in the frame interval where the display brightness value is received, when the image data is determined by the low-gradation image determination block to represent the low-gradation image.
15. In a method for driving a display device, Step of receiving image data and display brightness values; A step of determining whether the above image data represents a low-gradation image; If the above image data does not represent the low-gradation image, a step of performing a smooth dimming operation to gradually change the brightness of the display panel of the display device to a brightness corresponding to the display brightness value over a plurality of frame intervals; and A method for driving a display device comprising the step of changing the brightness of the display panel to a brightness corresponding to the display brightness value without performing the smooth dimming operation when the above image data represents the low-gradation image.
16. In claim 15, the step of performing the smooth dimming operation is, A driving method for a display device characterized by including a step of gradually changing gamma voltages over the plurality of frame intervals.
17. In claim 15, the step of determining whether the image data represents the low-gradation image is, A step of counting the number of pixels among a plurality of pixels of the above display panel in which the image data represents a grayscale lower than or equal to a reference grayscale; A step of comparing the number of the above-counted pixels with a reference number; and A method for driving a display device characterized by including a step of determining that the image data represents the low-gradation image when the number of pixels counted above is greater than or equal to the reference number.
18. A driving method for a display device according to claim 17, wherein the reference grayscale and the reference number have predetermined fixed values.
19. In claim 17, the above reference gradation can be set by a gradation option, and A method for driving a display device characterized in that the above-mentioned standard number can be set by a number option.
20. A processor that provides image data and display brightness values; A display panel including a plurality of pixels; and It includes a panel driving unit that receives the image data and the display brightness value and drives the display panel based on the image data and the display brightness value. The above panel driving unit is, Determining whether the above image data represents a low-gradation image, and If the above image data does not represent the low-gradation image, a smooth dimming operation is performed to gradually change the brightness of the display panel to a brightness corresponding to the display brightness value over multiple frame intervals. An electronic device characterized by not performing the smooth dimming operation when the above image data represents the low-gradation image.

Description

Display device, method of operating a display device, and electronic device The present invention relates to a display device, and more specifically, to a display device that performs a dimming operation, a method for driving the display device, and an electronic device including the display device. A display device may include a display panel comprising a plurality of pixels and a panel driver for driving the display panel. The panel driver may include a scan driver for providing scan signals to the plurality of pixels, a gamma voltage generator for generating gamma voltages, a data driver for providing data voltages to the plurality of pixels based on the gamma voltages, and a controller for controlling the scan driver, the gamma voltage generator, and the data driver. The panel driving unit receives a display brightness value (DBV) from an external processor and can perform a dimming operation to change the brightness of the display panel to a brightness corresponding to the display brightness value by changing the gamma voltages according to the display brightness value. FIG. 1 is a block diagram showing a display device according to embodiments of the present invention. Figure 2 is a diagram showing examples of the luminance of a display panel according to the grayscale level at a plurality of display brightness values. FIG. 3 is a drawing for explaining an example of a smooth dimming operation performed in a display device according to embodiments of the present invention. FIGS. 4a and FIGS. 4b are drawings for explaining examples of brightness changes caused by smooth dimming operation in cases where smooth dimming operation is performed when the mode of the display device is switched. FIG. 5 is a block diagram showing an example of a controller included in a display device according to embodiments of the present invention. FIG. 6 is a diagram illustrating an example in which no change in brightness occurs due to smooth dimming operation when the mode of a display device according to embodiments of the present invention is switched. FIG. 7 is a flowchart illustrating a method of driving a display device according to an embodiment of the present invention. FIG. 8 is a diagram illustrating an example of how image data is determined to represent a low-gradation image. FIG. 9 is a flowchart illustrating a method of driving a display device according to another embodiment of the present invention. FIG. 10a is a diagram showing an example of dithered black image data, and FIG. 10b and FIG. 10b are diagrams for explaining examples in which it is determined whether the image data represents a low-gradation image. FIG. 11 is a flowchart illustrating a method of driving a display device according to another embodiment of the present invention. FIG. 12 is a diagram illustrating examples in which it is determined whether image data represents a low-gradation image. FIG. 13 is a flowchart illustrating a method of driving a display device according to another embodiment of the present invention. FIG. 14 is a diagram illustrating examples in which it is determined whether image data represents a low-gradation image. FIG. 15 is a block diagram showing an electronic device including a display device according to embodiments of the present invention. FIG. 16 is a block diagram showing an example of an electronic device according to embodiments of the present invention. Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the attached drawings. Identical components in the drawings are given the same reference numerals, and redundant descriptions of identical components are omitted. FIG. 1 is a block diagram showing a display device according to embodiments of the present invention, FIG. 2 is a diagram showing examples of luminance of a display panel according to a grayscale level at a plurality of display brightness values, FIG. 3 is a diagram explaining an example of a smooth dimming operation performed in a display device according to embodiments of the present invention, FIG. 4a and FIG. 4b are diagrams explaining examples of luminance change due to the smooth dimming operation in cases where the smooth dimming operation is performed when the mode of the display device is switched, FIG. 5 is a block diagram showing an example of a controller included in a display device according to embodiments of the present invention, FIG. 6 is a diagram explaining an example in which no luminance change due to the smooth dimming operation occurs when the mode of the display device according to embodiments of the present invention is switched. Referring to FIG. 1, a display device (100) according to embodiments of the present invention may include a display panel (110) comprising a plurality of pixels (PX) and a panel driver (120) for driving the display panel (110). In one embodiment, the panel driver (120) may include a scan driver (130) for providing scan signals (SS) to