Patent ID: 8599225

Claim:
A method of dimming a backlight assembly of a display panel comprising a plurality of light sources divided into at least one dimming area, the method comprising: providing image signals to the display panel; extracting a plurality of gray-scale values from image signals corresponding to the dimming area to calculate at least one of a mean value, a median value or a mode value of the gray-scale values; calculating at least one of a variance, a standard deviation, a kurtosis, a skewness, a central moment, and an image moment using at least one of a mean value, a median value or a mode value, wherein the image moment comprises a raw image moment of an n-th degree or lower and a central image moment of the n-th degree or lower, where n is a number of the gray-scale values; calculating a maximum value of the gray-scale values; determining a representative gray-scale value corresponding to the dimming area using the calculated values; determining a dimming function for the light sources included in the dimming area based on the representative gray-scale value; and driving the light sources included in the dimming area based on the dimming function, wherein the representative gray-scale value GRE is represented by the following formula: γ 2 ≧0 ,GRE=α×m +(1−α)× P, γ 2 <0 ,GRE=α×m +(1−α)× P−βγ 1 , wherein m denotes the at least one of a mean value, a median value or a mode value, P denotes the maximum value, γ 1 denotes the kurtosis, γ 2 denotes the skewness, α = 1 C + K and β are predetermined constants, C is a predetermined constant satisfying 0.5≦C≦1.5, K is Max(| x |, | y |, √{square root over (|μ 11 |)}) if Max (  μ 20  ,  μ 02  ,  μ 12  3 ,  μ 21  3 ,  μ 30  3 ,  μ 03  3 ) ≥ T and zero (0) if Max (  μ 20  ,  μ 02  ,  μ 12  3 ,  μ 21  3 ,  μ 30  3 ,  μ 03  3 ) < T , T denotes a predetermined threshold value, x denotes an x-axis average raw image moment of the gray-scale values, y denotes a y-axis average raw image moment of the gray-scale values, and μ ij denotes the central image moment of an i-th degree along the x-axis and of a j-th degree along the y-axis.