It is well known that the homogeneous dot distribution is one of the important features affecting the image quality for B/W error diffusion method. However, when B/W error diffusion method is independently applied to each color channel, homogeneity between channels would not appear in color binary image. Non-homogeneity in color binary image often generates the overlap of the dots between channels. Especially, the overlap of cyan dots and magenta dots is noticeable to human eyes in color highlights. In order to prevent the overlap of cyan dots and magenta dots, this paper modulates the threshold value that makes the distance between dots in cyan channel and magenta channel be equal to the principal distance. Therefore, cyan dots and magenta dots are homogeneously distributed and the overlap of cyan dots and magenta dots can be prevented. The threshold value is increasing or decreasing according to the difference between the principal distance and the minimum distance. In color highlights, the principal distance is adjusted for satisfying the homogeneity between channels and the homogeneity in the respective channel. For the calculation of the minimum distance, this paper describes the 2D-MPOA(two dimensional minor pixel offset array) that is able to calculate the minimum distance efficiently.