A brightness compensation method for edge areas of flexible panels

Abstract

The present invention proposes a brightness compensation method for edge areas of flexible panels. Display pixels at the bend of the panel will have different brightness from the non-bend display area (Normal Display Area) in human vision due to the angle, so it is necessary to compensate for the brightness of this area. The compensation method uses the width (W) and height (H) of the pixel range of the panel bend display area (Partial Display Area) as a reference. After obtaining the relative position of the compensation area range by deducting the area of ​​the panel bend area from the actual panel pixel size, it is determined whether the pixel meets the compensation area range. Based on gamma adjustment, a set of brightness adjustment methods for display pixels in the panel bend area is established.

Description

Technical Field

[0001] The invention relates to a panel display method, and more particularly to a brightness compensation method for edge areas of flexible panels. Background Art

[0002] Foldable phones are becoming more mature in the AMOLED market. Considering the actual design requirements and the bendable characteristics of flexible panels, the appearance of the display is more flexible, making curved screens a trend and popular. In addition, flexible panels are also thin and impact-resistant, making them particularly suitable for portable products such as mobile phones, tablets or notebook computers. Generally speaking, when a flexible panel is bent or folded, the bending angle will cause the panel to display images. In this case, in addition to affecting the quality of the image display, it may also affect the accuracy of the touch.

[0003] The existing method uses an angle sensor to measure the final bending angle of the flexible panel, and performs corresponding image correction and image reconstruction based on the measured angle difference, and then projects it onto the display. However, this approach usually takes a long time to reconstruct and reacts slowly, and can also cause some software to miscalculate, resulting in obvious line segments appearing in the transition area of ​​the flexible panel, causing users to be unable to see the corrected image immediately when using the flexible display, which affects the viewing experience. Summary of the invention

[0004] The present invention provides a brightness compensation method for edge areas of a flexible panel, and proposes a method for implementing gamma brightness compensation for a panel bending area. The method comprises the following steps:

[0005] Step 1, define the compensation area, that is, the width of the panel bending area is W, and the height of the panel bending area is H;

[0006] Define the transition area, that is, the width of the panel transition area is W2, and the height of the panel transition area is H;

[0007] Step 2, calculate the compensation area range;

[0008] Step 3, judging whether it is in the compensation area and judging whether it is in the transition area;

[0009] Step 4: Transition area range compensation,

[0010] Step 5: Implement Digital Gamma Correction (DGC) on all pixel data R / G / B_partial_out and R / G / B_partial_W2_out in the compensation area obtained in steps 3 and 4 through LUT (Look Up Table).

[0011] Furthermore, the compensation area range in step 2 is calculated based on the pixel position and is defined as follows:

[0012] Partial_Area_Left_X_Start=1

[0013] Partial_Area_Left_X_End=W

[0014] Partial_Area_Right_X_Start=P_H_W-W

[0015] Partial_Area_Right_X_End=P_H_W,

[0016] The P_H_W is the abbreviation of Panel_Horizontal_Width.

[0017] Furthermore, the step 3 includes determining whether the horizontal position of the pixel is within the compensation area, and the determination method is to determine whether the bending area brightness compensation is performed based on whether the horizontal position of the input R / G / B_partial_in falls within the following range:

[0018] R / G / B_partial_in∈[Partial_Area_Left_X_Start,Partial_Area_Left_X_End]

[0019] or

[0020] R / G / B_partial_in∈[Partial_Area_Right_X_Start,Partial_Area_Right_X_End].

[0021] Furthermore, before the brightness compensation for the bending area, the step 3 also includes the identification and processing of the surrounding pixels between the bending area and the non-bending area, that is, the transition area. The determination of whether it is in the transition area range is based on whether the horizontal position of the input R / G / B_partial_In falls within the following interval. If it falls within, it is within the transition area range; if it does not fall within, it is not within the transition area range:

[0022]

[0023] Furthermore, Data_W2 is defined as the reference point when the input data of the bending area and the non-bending area are both 255, W255_Luv_Normal is defined as the maximum brightness of the non-bending area (in nit), and W255_Luv_Partial is defined as the maximum brightness of the bending area (in nit), and Data_Gain is obtained according to the proportional relationship:

[0024]

[0025] Furthermore, the compensation coefficient Gain_Set is obtained by linear interpolation:

[0026] The formula is as follows:

[0027]

[0028] in:

[0029] x0=Partial_Area_Left_X_End or Partial_Area_Right_X_Start

[0030] y0=Data_Gain

[0031] x1=Partial_Area_Left_X_End-W2 or Partial_Area_Right_X_Start+W2

[0032] y1=1

[0033] x = R / G / B_Partial_W2_in,

[0034] The Gain_Set obtained by formula (3) is used as the proportional compensation coefficient of the transition area:

[0035] R / G / B_Partial_W2_out_x=R / G / B_Partial_W2_in×Gain_Set.

[0036] Further, the step 5 comprises:

[0037] LUT (Look Up Table) establishes 25 binding points (BoudX) based on the relationship between 8-bit R / G / B_partial_out and Gamma voltage. The remaining 231 points are compensated by linear interpolation to achieve Digital GammaCorrection brightness adjustment.

[0038] The R / G / B_partial_in is the input, the R / G / B_partial_out is the output of the data in the compensation area that is not in the transition area, the R / G / B_Partial_W2_in is the input of the data in the transition area in the compensation area, the R / G / B_partial_W2_out is the output of the data in the transition area in the compensation area after compensation, and the R / G / B_Partial_W2_out_x is the input of the data in the transition area in the compensation area multiplied by the proportional compensation coefficient.

[0039] The Partial_Area_Left_X_Start is the starting position of the left side of the compensation range in the horizontal direction; the Partial_Area_Left_X_End is the ending position of the left side of the compensation range in the horizontal direction; the Partial_Area_Right_X_Start is the starting position of the right side of the compensation range in the horizontal direction, the Partial_Area_Right_X_End is the ending position of the right side of the compensation range in the horizontal direction, and the Panel_Horizontal_Width is the width in the horizontal direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 Shown is a flow chart for implementing the method of the present invention;

[0041] Figure 2 Shown is a schematic view of the bending area of ​​the panel of the present invention (Schematic View of Bending Area of ​​Panel);

[0042] Figure 3 Shown is a schematic diagram of the location of the compensation range of the present invention;

[0043] Figure 4 Shown is a current pixel location judgment flow chart (Current Pixel of Location Judgment Flow Chart) of the present invention;

[0044] Figure 5 It shows the data gain calculation of the bending area and the non-bending area (Data Gain of NormalLUT VS Partial LUT) of the present invention;

[0045] Figure 6 The figure shows the linear interpolation of the present invention;

[0046] Figure 7 The figure shows the corresponding relationship between the binding point and the gamma voltage of the present invention (LUT&BoudX Setting);

[0047] Figure 8 Shown are the gamma curves of the non-bending display area and the bending display area of ​​the present invention. DETAILED DESCRIPTION

[0048] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0049] See also Figure 1-8 The present invention provides a brightness compensation method for the edge area of ​​a flexible panel, and proposes a gamma brightness compensation method for the bending area of ​​the panel, see Figure 1 , including the following steps:

[0050] Step 1, define the compensation area, that is, the width of the panel bending area is W, and the height of the panel bending area is H;

[0051] Define the transition area, that is, the width of the panel transition area is W2, and the height of the panel transition area is H;

[0052] Step 2, calculate the compensation area range;

[0053] Step 3, judging whether it is in the compensation area and judging whether it is in the transition area;

[0054] Step 4: Transition area range compensation,

[0055] Step 5: Implement Digital Gamma Correction (DGC) on all pixel data R / G / B_partial_out and R / G / B_partial_W2_out in the compensation area obtained in steps 3 and 4 through LUT (Look Up Table).

[0056] See also Figure 2-3 Since the compensation area height (H) is the same as Panel_Vertical_Width, we only need to consider the horizontal starting and ending positions on the left and right sides of the compensation range. Figure 3 As shown, the compensation area range is calculated based on the pixel position:

[0057] Partial_Area_Left_X_Start=1

[0058] Partial_Area_Left_X_End=W

[0059] Partial_Area_Right_X_Start=P_H_W-W

[0060] Partial_Area_Right_X_End=P_H_W,

[0061] The P_H_W is the abbreviation of Panel_Horizontal_Width.

[0062] The R / G / B_partial_in is the input, the R / G / B_partial_out is the output of the data in the compensation area that is not in the transition area, the R / G / B_Partial_W2_in is the input of the data in the transition area in the compensation area, the R / G / B_partial_W2_out is the output of the data in the transition area in the compensation area after compensation, and the R / G / B_Partial_W2_out_x is the input of the data in the transition area in the compensation area multiplied by the proportional compensation coefficient.

[0063] The Partial_Area_Left_X_Start is the starting position of the left side of the compensation range in the horizontal direction; the Partial_Area_Left_X_End is the ending position of the left side of the compensation range in the horizontal direction; the Partial_Area_Right_X_Start is the starting position of the right side of the compensation range in the horizontal direction, the Partial_Area_Right_X_End is the ending position of the right side of the compensation range in the horizontal direction, and the Panel_Horizontal_Width is the width in the horizontal direction.

[0064] The horizontal position of the pixel is used to determine whether it is within the compensation area. The judgment relationship is as follows: Figure 4 As shown, the determination method is to determine whether the bending area brightness compensation will be performed based on whether the horizontal position of the input R / G / B_partial_in falls within the following range:

[0065] R / G / B_partial_in∈[Partial_Area_Left_X_Start,Partial_Area_Left_X_End]

[0066] or

[0067] R / G / B_partial_in∈[Partial_Area_Right_X_Start,Partial_Area_Right_X_End].

[0068] Before compensating the brightness of the bending area, the surrounding pixels of the bending area and the non-bending area must be distinguished and processed so that no obvious line segments appear in the transition area. The judgment of whether it is in the transition area range is based on whether the horizontal position of the input R / G / B_partial_In falls within the following range. If it falls within, it is within the transition area range; if it does not fall within, it is not within the transition area range:

[0069]

[0070] See also Figure 5 To avoid line segments in the transition area, Data_W2 is defined as the reference point when the input data of the bending area and the non-bending area are both 255. W255_Luv_Normal is defined as the maximum brightness of the non-bending area (in nit), and W255_Luv_Partial is defined as the maximum brightness of the bending area (in nit). Data_Gain is obtained according to the proportional relationship:

[0071]

[0072] See also Figure 6 , and then use linear interpolation to obtain the compensation coefficient Gain_Set:

[0073] The formula is as follows:

[0074]

[0075] in:

[0076] x0=Partial_Area_Left_X_End or Partial_Area_Right_X_Start

[0077] y0=Data_Gain

[0078] x1=Partial_Area_Left_X_End-W2 or Partial_Area_Right_X_Start+W2

[0079] y1=1

[0080] x = R / G / B_Partial_W2_in,

[0081] The Gain_Set obtained by formula (3) is used as the proportional compensation coefficient of the transition area:

[0082] R / G / B_Partial_W2_out_x=R / G / B_Partial_W2_in×Gain_Set.

[0083] All pixel data R / G / B_partial_out and R / G / B_partial_W2_out in the compensation area obtained in steps 3 and 4 are used through LUT (Look Up Table) to implement Digital Gamma Correction (DGC):

[0084] Assume that the relationship between 8-bit R / G / B_partial_out and Gamma voltage is corresponding, and 25 tie points (BoudX) are established as follows: Figure 7 As shown, the remaining 231 points are obtained by linear interpolation to implement the Digital Gamma Correction brightness adjustment method.

[0085] See also Figure 8 , assuming that the maximum brightness value of the non-bent display area (Normal Display Area) is 600nit and the gamma coefficient is 2.2, as shown by the blue line segment (below); the orange line segment (above) shows the bent display area (Partial Display Area) after DGC brightness compensation adjustment with a maximum brightness value of 700nit and a gamma coefficient of 2.2, and the overall brightness is increased by more than 17%.

[0086] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0087] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is limited by the appended claims and their equivalents.

Claims

1. A brightness compensation method for edge areas of a flexible panel, characterized in that: The following steps are involved: Step 1, define the compensation area, that is, the width of the panel bending area is W, and the height of the panel bending area is H; Define the transition area, that is, the width of the panel transition area is W2, and the height of the panel transition area is H; Step 2, calculate the compensation area range; Step 3, judging whether it is in the compensation area and judging whether it is in the transition area; Step 4, transition area range compensation; Step 5, all pixel data R / G / B_partial_out and R / G / B_partial_W2_out in the compensation area obtained in steps 3 and 4 are used for Digital Gamma Correction (DGC) through LUT (Look Up Table); The compensation area range in step 2 is calculated based on the pixel position and is defined as follows: Partial_Area_Left_X_Start=1 Partial_Area_Left_X_End=W Partial_Area_Right_X_Start=P_H_W-W Partial_Area_Right_X_End=P_H_W, The P_H_W is the abbreviation of Panel_Horizontal_Width; The step 3 includes determining whether the horizontal position of the pixel is within the compensation area, and determining whether to perform bending area brightness compensation is based on whether the horizontal position of the input R / G / B_partial_in falls within the following range: R / G / B_partial_in∈[Partial_Area_Left_X_Start,Partial_Area_Left_X_End] or R / G / B_partial_in∈[Partial_Area_Right_X_Start,Partial_Area_Right_X_End]; Before the brightness compensation for the bending area, the step 3 also includes the identification and processing of the surrounding pixels between the bending area and the non-bending area, that is, the transition area. The determination of whether it is within the transition area range is based on whether the horizontal position of the input R / G / B_Partial_W2_in falls within the following interval. If it falls within the transition area range, it is within the transition area range; if it does not fall within the transition area range, it is not within the transition area range: Define Data_W2 as the reference point when the input data of the bending area and the non-bending area are both 255, define W255_Luv_Normal as the maximum brightness of the non-bending area, the unit is nit, and define W255_Luv_Partial as the maximum brightness of the bending area, the unit is nit. Obtain Data_Gain according to the proportional relationship: Obtain the compensation coefficient Gain_Set using linear interpolation: The formula is as follows: in: x0=Partial_Area_Left_X_End or Partial_Area_Right_X_Start y0=Data_Gain x1=Partial_Area_Left_X_End-W2 or Partial_Area_Right_X_Start+W2 y1＝1 x = R / G / B_Partial_W2_in, The Gain_Set obtained by formula (3) is used as the proportional compensation coefficient of the transition area: R / G / B_Partial_W2_out_x=R / G / B_Partial_W2_in×Gain_Set; The step 5 comprises: LUT (Look Up Table) establishes 25 binding points (BoudX) based on the relationship between 8-bit R / G / B_partial_out and Gamma voltage. The remaining 231 points are compensated by linear interpolation to achieve Digital GammaCorrection brightness adjustment. The R / G / B_partial_in is input, the R / G / B_partial_out is output of data in the compensation area that is not in the transition area, the R / G / B_Partial_W2_in is input of data in the transition area in the compensation area, the R / G / B_partial_W2_out is output of data in the transition area in the compensation area after compensation, and the R / G / B_Partial_W2_out_x is input of data in the transition area in the compensation area multiplied by a proportional compensation coefficient; The Partial_Area_Left_X_Start is the starting position of the left side of the compensation range in the horizontal direction; the Partial_Area_Left_X_End is the ending position of the left side of the compensation range in the horizontal direction; the Partial_Area_Right_X_Start is the starting position of the right side of the compensation range in the horizontal direction, the Partial_Area_Right_X_End is the ending position of the right side of the compensation range in the horizontal direction, and the Panel_Horizontal_Width is the width in the horizontal direction.

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