Abstract: An evaporator suitable for absorbing heat from a heat source is provided. The evaporator includes a top board, a bottom board, a side frame, and at least one porous member. The side frame connects the top board and the bottom board. The porous member is disposed between the top board and the bottom board and within the side frame. The part of the top board covering the porous member is a heat conducting portion near the heat source. The evaporator has at least one first channel, at least one second channel, a fluid inlet, and a fluid outlet. The first channel is adjacent to the bottom board and the porous member for containing a working fluid. The second channel is adjacent to the top board and the porous member for containing the working fluid. The fluid inlet communicates with the first channel. The fluid outlet communicates with the second channel.

Abstract: A light emitting diode (LED) illumination apparatus including an illumination module, a heat dissipating unit and a loop heat pipe (LHP) device is provided. The illumination module includes a base and many LEDs. The LEDs are disposed on the base. The LHP device contains working fluid and includes an evaporator, a condenser, a first transmitting pipe and a second transmitting pipe. The evaporator is associated with the base and has an outlet, an inlet and a chamber. The condenser is conformably associated with the heat dissipating unit. The condenser has an inlet and an outlet, wherein at least one part of the condenser stretches in a curved pipe shape along a surface of the heat dissipating unit. The first transmitting pipe communicates the evaporator outlet to the condenser inlet. The second transmitting pipe communicates the condenser outlet to the evaporator inlet.