Abstract: The light guide plate is a key component of backlight units, which determines efficiency and uniformity of light emission. Taking the edge-light from two LEDs as examples, a model was set up to derive the rule of scattering netted dot arrangement by the optical theory. A brief formula for dot arrangement was obtained. In order to achieve wider applications, the rule of the dot arrangement on the light guide plate was deduced for more LEDs. In order to achieve equivalent application, a rule of dot arrangement on the plate with linear light source was acquired.