摘要:
The present invention provides an optical module using optical waveguides which permits easy fabrication of a PLC type optical multiplexer/demultiplexer with reduced loss. The optical module comprises cores which are contiguous to each other through a dicing groove adapted to position and fix an optical functional part such as a wavelength selection filter and a core branched from the said cores. A slight gap is present between the former and the latter core and both cores are narrower in width in the vicinity of the dicing groove than the other portions.
摘要:
The present invention provides an optical module using optical waveguides which permits easy fabrication of a PLC type optical multiplexer/demultiplexer with reduced loss. The optical module comprises cores which are contiguous to each other through a dicing groove adapted to position and fix an optical functional part such as a wavelength selection filter and a core branched from the said cores. A slight gap is present between the former and the latter core and both cores are narrower in width in the vicinity of the dicing groove than the other portions.
摘要:
Disclosed is a semiconductor optical integrated device and method of fabricating the device, the device having a plurality of quantum well structures, formed on a single substrate, acting as optical waveguides, the plurality of quantum well structures respectively having different lattice mismatches with the substrate and/or different strains (e.g., respectively compressive strain and tensile strain). The method includes selectively depositing the quantum well structures by, e.g., organometallic vapor phase epitaxy on growth regions of the substrate, the growth regions being defined by insulating layer patterning masks, with a width of the growth regions and/or a width of the patterning mask being different for the different quantum well structures. Each quantum well structure includes quantum well layers of III-V or II-VI compound semiconductor material, the Group III or Group II elements each including at least two elements, one having a relatively large atomic diameter and another having a relatively small atomic diameter. Also disclosed is a light receiver that can independently absorb TE-mode and TM-mode light in series, which can be used in a polarized-wave diversity receiver for coherent optical communication.
摘要:
An optical transmitter/receiver module of wavelength division multiplexing type which undergoes a reduced excess loss resulting from the displacement of a dicing position is fabricated with a high yield rate. An optical waveguide for guiding reflected light from a wavelength selection filter has a core substantially larger in size than the core of each of the other optical waveguides.
摘要:
A passive region is provided on one side or both sides of a waveguide-type optical modulator. Thereby, it is possible to obtain a high-speed optical modulator package superior in mechanical strength, thermal characteristic, high-frequency characteristic, and extinction characteristic. Moreover, it is possible to increase the operating speed of an optical fiber transmission equipment by applying the optical modulator package to the optical fiber transmission equipment.
摘要:
A semiconductor optical device, a fiber optical amplifier and an optical transmission system are disclosed. The semiconductor optical device is excellent in the stability of the coupling efficiency and the splitting ratio of a Y-branch. Both the fiber optical amplifier and the optical transmission system operate in a stable manner over a long period of time even if an optical waveguide is employed which is operative in a multi-mode in the transverse direction. The semiconductor optical device has an optical waveguide, a mode filter for transmitting therethrough light of a fundamental mode and blocking the propagation of light of a higher-order mode. The mode filter is provided in at least a part of the optical waveguide. The width of the mode filter is larger than that of the optical waveguide.
摘要:
An optical signal is incident on a semiconductor optical waveguide with a grating and is reflected or transmitted therethrough to thereby perform dispersion compensation. Application of an electric field or implantation of carriers can be effected in the optical waveguide by means of electrodes attached in the optical waveguide. In addition, a temperature of the optical waveguide can be varied by a resistance heater. By using these measures, the dispersion compensation wavelength and the dispersion compensation intensity can be adjusted.
摘要:
In the structure of the device of the invention, a supper-lattice buffer layer is formed between the undoped layer and doped layers. This super-lattice buffer layer serves as a carrier-piling up layer in place of the undoped layer in the conventional device. Thus, the amounts of the piled-up carriers in the undoped layer can be greatly reduced and hence no band filling effect occurs in the undoped layer. Consequently, an optical device having a flat frequency characteristic can be produced without losing its modulating characteristic.
摘要:
An optical crossconnect apparatus which includes one terminal connected to a transmission path from one optical transmission terminal station and another terminal connected to a transmission path from another optical transmission terminal station, a first optical signal switch having “M1” ports and “N1” ports, through which the optical signal can pass, a second optical signal switch having “M2” ports and “N2” ports, through which the optical signal can pass, and “L” optical signal repeaters, one end connected to the “N1” ports of the first optical signal switch, and the other end connected to the “N2” ports of the second optical switch. The “N1” and the “N2” ports are equal to “L” optical signal repeaters. The “M1” ports of the first optical signal switch connected to the one terminal, and the “M2” ports of the second optical signal switch connected to the other terminal are larger than, or equal to 2.
摘要:
A lumped element non-reciprocal circuit device is downsized without an increase in an insertion loss. A lumped element non-reciprocal circuit device comprises a plurality of center electrodes; a microwave magnetic material; a permanent magnet; and a metal case that serves as a magnetic yoke, wherein the center electrode is disposed on a main surface of the microwave magnetic material, the microwave magnetic material has a side surface perpendicular to the main surface, and a shortest distance between the side surface of the microwave magnetic material and the metal case is set to be equal to or larger than a thickness of the microwave magnetic material and equal to or smaller than 2.3 times of the thickness of the microwave magnetic material.