1. A method for determining edges of an overlapping region between a color filter and a black matrix, comprising: acquiring a measurement area to be detected which includes a color filter, a black matrix, and an overlapping region therebetween, drawing an original gray-scale value curve and a differential gray-scale value curve of the measurement area to be detected, and determining extremums of the differential gray-scale value curve according to a predetermined extremum range, obtaining a gray-scale value of the overlapping region between the color filter and the black matrix according to gray-scale values of the color filter and the black matrix in the measurement area to be detected, based on a first preset rule, establishing a threshold value according to the gray-scale values of the color filter, the black matrix, and the overlapping region, based on a second preset rule, and obtaining, according to two intersections of the threshold value and the original gray-scale value curve, two extremums of the differential gray-scale value curve which are the closest to said two intersections respectively, and determining the edges of the overlapping region between the color filter and the black matrix based on said two extremums.