Patent ID: 8052387

Claim:
A cooling fan, comprising a hub and a plurality of blades extending radially from the hub, each of the blades being divided into a plurality of strip zones, projections of a plurality of homocentric circles concentric with a center of the hub on the blades being defined as boundaries of the zones, all but one of the zones being coated with a layer of paint with different colors to present a rainbow-liked image when the fan is in operation; wherein each of the blades is divided into first, second, third, fourth, fifth, sixth and seventh zones; wherein the first zone is the nearest zone to the hub and is uncoated, and the seventh zone is the furthest zone from the hub; and wherein each of the second, fourth and sixth zones is divided into two parts by a radial line, the color of the layer of paint on the two parts of the second zone is red and blue, respectively, the color of the layer of paint on the two parts of the fourth zone is blue and yellow, respectively, the color of the layer of paint on the two parts of the sixth zone is yellow and red, respectively, and the color of the layer of paint on the third, fifth and seventh zones is blue, yellow and red, respectively.