A golf ball is provided with five sets of dimples, the dimples of each set having a different diameter and a different depth. As the diameter of the dimples decreases, the depth of the dimples increases, and the aspect ratio of the depth to diameter for each set is within the range of 0.025 to 0.055...http://www.google.fr/patents/US4979747?utm_source=gb-gplus-shareBrevet US4979747 - Golf ball
