Abstract: A flat heat pipe includes a casing, a wick structure received in the casing, and a working medium contained in the casing and saturated in the wick structure. The casing has an upper plate and a bottom plate opposite to the upper plate. The wick structure is attached only to the bottom plate of the casing. The wick structure spaces from the upper plate with a vapor channel defined between the upper plate and the wick structure.

Abstract: A heat pipe includes a casing and a plurality of wick layers. The casing has an inner wall. The wick layers stack at an inner surface of the casing in turn. The wick layers respectively define a plurality of pores therein. Diameters of the pores of each of the wick layers gradually decrease from the inner wall to center of the casing.

Abstract: The present invention relates to the technical field of measuring light source, specifically, to the method for measuring the luminous flux of LED. In the present invention, a reflecting cup is used as a collector of the luminous flux of LED. The collector has two sectional openings in the direction perpendicular to the symmetric axis thereof, which are positioned in the front and in the rear respectively, one of them positioned at the bottom end of the collector and having a smaller radius is used to input the light emitted by LED to be measured, the other positioned in the front end of the collector and having a larger radius is used to output the light to the detector placed in this position. Specifically, LED is fixed at the bottom end of the collector with a fixture, the light emitted by LED is directed toward the large opening of the collector, and the photometer is fixed closely at the large opening of the collector to receive light signals.

Abstract: A flat heat pipe includes a casing and a wick structure received in the casing. The casing has a first lateral portion and a second lateral portion. Each of the first lateral portion and the second lateral portion has a C-shape configuration, and the second lateral portion has an opening facing an opening of the first lateral portion. The wick structure is attached to an inner surface of only one of the first and lateral portions of the casing. The inner surface of the other of the first and second lateral portions without the wick structure attached thereto defines a first vapor channel, and an inner surface of the wick structure defines a second vapor channel. The first vapor channel has a height greater than the second vapor channel.