Abstract: Provided is a polarization division multiplexed optical OFDM transmitter. The polarization division multiplexed optical OFDM transmitter includes a data demultiplexer, a training symbol generation unit and an optical up-converter and polarization division multiplexing unit. The data demultiplexer divides a transmission signal into a plurality of groups. The training symbol generation unit allocates a plurality of training symbols for each OFDM data which is included in the respective multiplexed groups, and allocates repetitive data in a time domain for the respective training symbols for data of 0 to periodically appear for the respective training symbols in a frequency domain. The optical up-converter and polarization division multiplexing unit performs optical frequency band conversion and polarization division multiplexing on an output of the training symbol generation unit to output a polarization division multiplexed optical OFDM signal corresponding to a plurality of polarization components.

Abstract: Provided is an optical receiver used for an optical communication system, more particularly, a polarization split-phase shift demodulation coherent optical receiver. An optical hybrid includes a first optical splitter, a phase shift waveguide, a second optical splitter, and an optical coupler. The first optical splitter splits a first input optical signal to output first output optical signals. The phase shift waveguide receives the first output optical signals and controls and outputs the first output optical signals such that the first output optical signals have different phases. The second optical splitter splits a second input optical signal to output a plurality of second output optical signals. The optical coupler couples the first output optical signals one-to-one with the second output optical signals, respectively.

Abstract: A compound containing a crosslinkable moiety, a curable prepolymer, a blend, and a polymer sheet obtained therefrom, and an optical waveguide for optical interconnection. The compound is represented by the formula below: Ar—H wherein Ar includes a crosslinkable moiety at one end, a moiety selected from the group consisting of —O—, —S—, —COO—, —CO—, —COS—, —SO2—, and —NH—, and one or two repeating units selected from the group consisting of the following repeating units: wherein A in the repeating unit is carbon or nitrogen, and X is hydrogen or halogen. At least one of the core and the cladding in the optical waveguide includes the polymer sheet.

Abstract: Provided are a flexible waveguide structure and an optical interconnection assembly. The flexible waveguide structure includes a thin film strip core, an inner cladding layer, and an outer cladding layer. The thin film strip core has opposed first and second surfaces and is formed of a metal. The inner cladding layer covers at least one of the first and second surfaces of the thin film strip core. The outer cladding layer covers the inner cladding layer. The inner cladding layer has a refractive index higher than that of the outer cladding layer.

Abstract: Provided are a light emitting device and an optical coupling module. The device includes a substrate, a light emitting part provided to the substrate, and a reflecting part provided to a lower surface of the substrate. The light emitting part includes an active pattern disposed on the substrate, an upper mirror provided to an upper portion of the active pattern, and a lower mirror provided to a lower portion of the active pattern. The light emitting part may emit light normal to the substrate, and the reflecting part may reflect the emitted light to a side surface of the substrate.

Abstract: Provided are an enhanced structure of a coplanar waveguide that is a kind of transmission line used for optical communication for radio frequency (RF), and an optical communication module employing the same. While having a basic structure including a conductive strip and ground strips at both sides of the conductive strip on a dielectric substrate, the coplanar waveguide has the structure in which metal patterns of a portion of the conductive strip located around points where an RF propagation direction is changed and of a portion of an inside ground strip are removed to make electrical lengths of an outside ground strip and the inside ground strip similar each other. Using the coplanar waveguide, it is possible to fabricate an optical module that has an optimized RF characteristic and also can freely change an RF propagation direction of several tens GHz, without an additional process.

Abstract: Provided is a semiconductor optical modulator device in which a resistor for impedance matching is integrated in a device in order to improve performance and to reduce cost during the fabrication of an ultra high speed optical modulator module. A doped layer in an epitaxial layer of the optical modulator device is used as a resistor for impedance matching. According to this method, it is possible to more easily realize an optical device compared with optical device fabrication processes in which additional resistors are used in the outside and the inside of the device for impedance matching.

Abstract: The present invention provides the photodetector comprising a lower cladding layer including a n-type doped region, an absorbing layer, an upper cladding layer including a p-type doped region, and ohmic electrodes connected to said lower cladding layer and said upper cladding layer, wherein said p-type doped region extends to be formed into said absorbing layer by a predetermined length. In accordance with present invention, by reducing effect of the hetero junction barrier where holes move in the intrinsic region, the operating voltage can be decreased and the bandwidth can be improved.

Abstract: Disclosed herein are a SSC integrated optical device and a method of manufacturing the same. When a taper waveguide in a SSC region is formed, a width and a thickness are controlled exactly by means of a selective wet etch method. In particular, a start portion of the taper waveguide is formed to have a mesa structure or a reverse-mesa structure. Accordingly, it is possible to control process parameters reproducibly, reduce the cost for an optical alignment and improve an optical coupling efficiency and quantum efficiency remarkably.

Abstract: The present invention provides the photodetector comprising a lower cladding layer including a n-type doped region, an absorbing layer, an upper cladding layer including a p-type doped region, and ohmic electrodes connected to said lower cladding layer and said upper cladding layer, wherein said p-type doped region extends to be formed into said absorbing layer by a predetermined length.