An active device array substrate includes a substrate, scan and data lines defining pixel regions, active devices, pads, color filter layers, and pixel electrodes. The active devices respectively correspond to the pixel regions and electrically connect the corresponding scan lines and data lines. The pads disposed within the corresponding pixel regions connect the active devices. The color filter layers covering the pixel regions are disposed on the active devices and the pads. Each color filter layer has an opening exposing the corresponding pad and having a polygonal shape. The pixel electrodes are located on the color filter layers in the pixel regions. Each pixel electrode connects the pad downward via the corresponding opening and has parallel fine slits having a first extension direction. An included angle between the first extension direction and an extension direction of a first side of the opening is θ1, and 60°≦θ1≦90°.