HEAT SINK

To fully exert a heat transfer function of a heat pipe to improve a cooling performance even when a size of a heating element is small.SOLUTION: A heat sink 1 comprises a heat receiving member 2 and first and second heat pipes 3 and 4. The first and second heat pipes 3 and 4 are laminated in an order of the first heat pipe 3 and the second heat pipe 4 along a first direction from a heat receiving surface of the heat receiving member 2 toward a back surface 2b. The second heat pipe 4 includes a proximity heat pipe 43 arranged in a first area Ar1 in which a heating element 100 is arranged, and a separation heat pipe 44 arranged in a second area Ar2 other than the first area Ar1. An area of the first heat pipe 3 which overlaps with the separation heat pipe 44 is larger than an area of the first heat pipe which overlaps with the proximity heat pipe 43.SELECTED DRAWING: Figure 3 【課題】発熱体のサイズが小さい場合であっても、ヒートパイプの熱輸送機能を十分に発揮させ、冷却性能を向上させること。【解決手段】ヒートシンク１は、受熱部材２と、第１，第２のヒートパイプ３，４とを備える。第１，第２のヒートパイプ３，４は、受熱部材２における受熱面から背面２ｂに向かう第１の方向に沿って第１のヒートパイプ３及び第２のヒートパイプ４の順に積層されている。第２のヒートパイプ４は、発熱体１００が配設される第１の領域Ａｒ１に配設される近接ヒートパイプ４３と、第１の領域Ａｒ１以外の第２の領域Ａｒ２に配設される離間ヒートパイプ４４とを備える。第１のヒートパイプ３は、近接ヒートパイプ４３と重なり合う面積よりも離間ヒートパイプ４４と重なり合う面積の方が大きい。【選択図】図３