Grayscale adjustment method and grayscale adjustment device for display panel

A grayscale adjustment device of a display panel, comprising:

• an image capture module configured to capture an image of the display panel, to obtain a current image;
• an identification module configured to identify a non-uniform block of the current image, and detect an original output brightness value and an original input grayscale of the non-uniform block;
• a calculation module configured to determine a target input grayscale corresponding to a preset target brightness value according to an actual gamma curve value, wherein the actual gamma curve value is obtained by testing the display panel, wherein the calculation module further obtains n reference images of the display panel with different input grayscales, and calculates the reference gamma curve value of each of the reference images to set a mean value of the reference gamma curve values as the actual gamma curve value, wherein n is an integer higher than or equal to 2, and the calculation module detects a reference input grayscale and a reference output brightness value of each of the reference images, and calculates the reference gamma curve value of each of the reference images according to the reference input grayscale, the reference output brightness value and a gamma mathematic model, wherein the gamma mathematic model is:
• Tx
• -
• To
• T
• ⁢
• ⁢
• 255
• -
• To
• =
• (
• Lx
• 255
• )
• Gamma
• wherein Tx is the reference output brightness value, T255 is the output brightness value corresponding to the input grayscale with a value of 255, T0 is the output brightness value corresponding to the input grayscale with a value of 0, Lx is the reference input grayscale, and Gamma is the actual gamma curve value;
• an adjustment module configured to set a difference between the original input grayscale and the target input grayscale as a grayscale compensation value of the non-uniform block.

A grayscale adjustment method of a display panel, comprising:

• using an image capture module to capture an image of the display panel, to obtain a current image;
• using an identification module to identify a non-uniform block of the current image, and detecting an original output brightness value and an original input grayscale of the non-uniform block;
• using a calculation module to obtain n reference images of the display panel with different input grayscales, and calculate a reference gamma curve value of each of the reference images, and set a mean value of the reference gamma curve values as an actual gamma curve value, wherein n is an integer higher than or equal to 5, wherein the step of calculating the reference gamma curve value of each of the reference images, comprises:
• detecting a reference input grayscale and a reference output brightness value of each of the reference images;
• calculating a reference gamma curve value of each of the reference images according to the reference input grayscale, the reference output brightness value and a gamma mathematic model, wherein the gamma mathematic model expresses a corresponding relationship between the reference input grayscale and the reference output brightness value, and the gamma mathematic model is:
• Tx
• -
• To
• T
• ⁢
• ⁢
• 255
• -
• To
• =
• (
• Lx
• 255
• )
• Gamma
• wherein Tx is the reference output brightness value, T255 is the output brightness value corresponding to the input grayscale with a value of 255, T0 is the output brightness value corresponding to the input grayscale with a value of 0, Lx is the reference input grayscale, and Gamma is the actual gamma curve value;
• using the calculation module to determine a target input grayscale corresponding to the preset target brightness value according to the actual gamma curve value;
• using an adjustment module to set a difference between the original input grayscale and the target input grayscale as a grayscale compensation value of the non-uniform block;
• transmitting the grayscale compensation value to the display panel, and setting a sum of the grayscale compensation value and the original input grayscale of the non-uniform block as a new input grayscale of the non-uniform block in the display panel, to eliminate the non-uniform block of the current image.