a three - dimensional display including a display and a micro - lens is provided . the display has a plurality of pixel units thereon , and each pixel unit has a pixel pitch i . the micro - lens is disposed at a side of the display , the micro - lens has a plurality of lens units thereon , and each lens unit has a lens pitch l . a right eye viewing zone and a left eye viewing zone are formed if an image displayed from the display passes though the micro - lens , wherein a distance between the center of the right eye viewing zone and the center of the left eye viewing zone is w z , and lens pitch l satisfies : 2  i & gt ; l & gt ; 2  i × w z w z + i , w z is between 70 and 500 mm and i is between 0 . 1 and 500 μm .