Abstract: There is provided a light emitting diode package having at least two heat sinks. The light emitting diode package includes a main body, at least two lead terminals fixed to the main body, and at least two heat sinks of electrically and thermally conductive materials, the heat sinks being fixed to the main body. The at least two heat sinks are separated from each other. Thus, high luminous power can be obtained mounting a plurality of light emitting diode dies in one LED package. Further, it is possible to embody polychromatic lights mounting LED dies emitting different wavelengths of light each other in the LED package.

Abstract: A fault localization apparatus for an optical line in a wavelength division multiplexed passive optical network is disclosed. The apparatus can detect light loss and fault positions as a channel exhibiting an abnormal receiving state of signals received by each of the upstream receivers is checked, and a monitoring optical signal is used, in which the monitoring optical signal is generated as a pulse is inputted to a light source of the downstream transmitter corresponding to the channel showing such an abnormal receiving state. The apparatus according to the present invention can detect fault positions of optical lines between the central office and the remote nodes and between the remote nodes and the optical network units, since the light source of downstream channel in which faults occur is used as a monitoring light source. The apparatus according to the present invention can be cost-effectively implemented.

Abstract: A communication recovering system for a wavelength division multiplexed passive optical network (WDM PON). The communication recovering system can recover fault of optical fibers between the central office and the remote nodes without additional optical fibers by grouping two remote nodes and employing an AWG having periodic transmission characteristics, and can also simply and rapidly recover such a fault with minimal optical loss using an AWG of 2×N structure and an On-Off optical switch, although protection optical fibers are additionally installed therein. The system can rapidly recover fault of optical fibers between a local office and optical network units, 1:N manner, using 2×2 optical switches, which are installed to each of the optical network units, a reserved transmitter and receiver, and a transceiver.