This invention discloses a method to control highlighting of certain part of image on a display, wherein the image processing unit forwards the physical coordinates acquired by the host computer's coordinate acquisition unit to the coordinate transmission unit, and draws a regular shape centered on the acquired physical coordinates, and then displays the area within the regular shape at the normal brightness, and the rest outside the area at the corresponding proportion of low brightness. According to the method of the present invention, the attention of the doctor is focused on the specific or targeted area, the interferences caused by the surrounding images and the brightness are shielded, and the images in the specific pattern area is easier to identify. Thus, it will help doctors to improve the efficiency and accuracy of medical diagnosis for a lesion and make medical consultation and education more convenient.
