Abstract: A core for propagating optical signals, and a pair of first and second cladding layers disposed opposite each other, between which the core is disposed, are provided, which prevents light scattering between the cladding and the core, and reduces polarization dependency. The first cladding layer on which the core is formed has a multilayer film on the boundary face side contacting the core, and the multilayer film has a multilayer structure in which a distortion stress exists among multiple materials.

Abstract: A higher-order dispersion compensator for tuning a polarization controlled signal having a first order polarization mode dispersion component, a second order polarization mode dispersion component, and a variable chromatic dispersion component. The compensator includes a first tuning element that adjusts the first order polarization mode dispersion component of the polarization controlled signal, and a second tuning element that adjusts the second order polarization mode dispersion component and the variable chromatic dispersion component of the polarization controlled signal. The first tuning element, which includes a differential delay line, includes a polarization beam splitter coupled to receive the polarization controlled signal. The first tuning element includes a first waveguide optically coupled to receive a first polarization component and a second waveguide optically coupled to receive a second polarization component. A first tuning mechanism is provided that tunes one of the gratings.

Abstract: A device wavelength division multiplex optical transmission system has the wavelengths of the optical carriers arranged so as to reduce the effect of in-band crosstalk which results from unwanted side bands to the carriers. Possible wavelengths are placed on an equally spaced wavelength grid, and the transmitted channels are organized into groups of three each of which is placed on four adjacent grid positions, one of which is unused. Adjacent groups are spaced apart by two or more vacant grid positions.

Abstract: An arrayed-waveguide grating type optical multi-demultiplexer includes input waveguides, a first slab waveguide, a channel waveguide array, a second slab waveguide, and output waveguides. A pair of different refractive index regions, each having a refractive index different from that of the second slab waveguide, are formed on the second slab waveguide near a boundary between the second slab waveguide and channel waveguide array. The different refractive index regions project in peninsular shapes from both side portions of the slab waveguide. Light traveling from each waveguide of the channel waveguide array toward the output waveguides passes through the different refractive index regions. An optical distribution with a flattened field-distribution peak is created at a boundary between the second slab waveguide and output waveguides.

Abstract: Disclosed are an optical fiber cable comprising an optical fiber and at least one covering layer formed on the outer periphery of the optical fiber, at least one layer of the covering layer being made of a material comprising a resin component containing a polyamide polymer, wherein a flexural modulus E upon displacement of 1 mm is within a range from 2 to 15 (N/mm) and the optical fiber cable passes a flame resistance test in accordance with DIN 72551-5, and an optical fiber cable with a plug using the optical fiber. Therefore, they have excellent flame resistance and good handling properties.

Abstract: The invention provides a process for forming optical components and new optical materials utilizing electron beam irradiation. The process comprises selectively irradiating optical materials to alter their index of refraction gradient three dimensionally. With the inventive process, new optical materials can be created that have enhanced optical properties over the un-irradiated material. The invention also provides a process in which optical components can be fabricated without requiring a planar/multiple layer process, thereby simplifying the fabrication of these optical components. The inventive process uses a controlled electron beam to alter the properties of optical materials. By using the radiation of a controlled electron beam, controlled changes in the index of refraction gradient of optical materials can be obtained. Further, radiation of the electron beam can be used to create new optical materials from materials not previously believed to be suitable for optical applications.

Abstract: Devices with two or more coupled resonators to produce narrow spectral responses due to interference of signals that transmit through the resonators and techniques for operating such devices to achieve certain operating characteristics are described. The devices may be optical devices where optical resonators such as whispering gallery mode resonators may be used. In one implementation, at least one of the coupled optical resonators is a tunable resonator and is tuned to change its resonance frequency to tune the spectral response of the device. The described devices and techniques may be applied in optical filters, optical delays, optical waveform generators, and other applications.

Abstract: An illumination optical system includes a light source which emits light, and a light separation/integration device having a diffraction device on at least one incident side. The diffraction device diffracts light to decrease an incident angle to a predetermined range. An image display apparatus includes the illumination optical system, an image optical system which modulates light incident from the illumination optical system to form an image, and a projection optical system which projects the light reflected from the image optical system onto a screen.

Abstract: A light amplifier includes a source of multiple light beams, each modulated with the same information, and a plurality of light amplifying optical fibers, each amplifying one of the light beams. The amplified light from each amplifying fiber is converted to electric form, and the electrical signals are summed to add the information and average the noise. In one embodiment, the bundle of fibers is twisted as it is wound about a cylinder, to average the compressive and tension forces on the fibers of the bundle. In another embodiment, a common cladding surrounds a bundle of fibers.

Abstract: A combination ribbon for bows or other decorative uses, which includes a central ribbon with a fiber optic cable therein, or at least one translucent cable jacket on one edge of the ribbon with a fiber optic cable therein, which cable has portions of its sheath removed to provide light patterns upon the shining of a light source therein.

Abstract: An optical waveguide member is inserted into a tubular member. The tubular member is elongated with heating and fusion-bonded to the optical waveguide member. Thus, a formed body is obtained. The formed body is cut into a predetermined length to obtain an optical waveguide member. The tubular member is preferably made of a crystallized glass with crystals deposited therein at least in the state of the formed body.

Abstract: A photosensitive sol-gel film containing an organometallic photosensitizer is deposited on the oxide containing surface layer of a silicon substrate. A pattern of white or ultra violet light incident to the photosensitive sol-gel film results in the unbinding of the photosensitizer from the exposed regions of the sol-gel film. A subsequent succession of first and second heating steps results in, first, the removal of the photo sensitizer constituents from the exposed regions of the sol-gel film and, second, the removal of the organic constituents from the exposed regions, resulting in regions doped with a metal oxide with non linear optical properties, such as semicondutive, electro-optic, magneto-optic, etc. properties. Optical switches, couplers, waveguides, splitters, interferometers wavelength division multiplexer, Bragg gratings and more can be fabricated. A glass substrate also may be employed, instead of a silicon, in which case a separate silicon oxide surface layer is unnecessary.

Abstract: An optical interface between an optical fiber and a laser is provided. The optical fiber has a core and an end. The optical interface includes a mirror that is capable of receiving an optical output of the laser and of reflecting the optical output to the end of the optical fiber such that a chief ray of the optical output is incident on the core of the optical fiber. The optical interface also includes a lens located such that the chief ray of the optical output traverses a center of the lens. Such optical interface may be used in a transmitter optical subassembly (TOSA) having a vertical TO package for un-cooled lasers.

Abstract: An optical waveguide device includes a substrate, a metal layer arranged on the substrate, a plurality of claddings arranged on the metal layer via grooves, a core, arranged in each of the plurality of claddings, for transmitting lights, optically non-transmissive material coating the insides of the grooves, and optically non-transmissive and electrically insulating material coating the top faces of the claddings.

Abstract: A standard CMOS process is used to fabricate optical and electronic devices at the same time on a monolithic integrated circuit. In the process, a layer of metallic salicide can be depsoited on those selected portions of an integrated circuit, where it is desired to have metallic contacts for electronic components, such as transistors. The deposition of a salicide into the core of an optical waveguide will damage the waveguide and prevent the passage of light through that section of the waveguide. Prior to the deposition of the salicide, a salicide blocking layer is deposited on those parts of an integrated circuit, such as on an optical waveguide, which are to be protected from damage by the deposition of salicide. The salicide blocking layer is used as one layer of the cladding of a silicon waveguide.

Abstract: An optical isolator having an optical element, comprised of an incoming side polarizer, a Faraday rotator, and an outgoing side polarizer superposed in the order of mention in the direction of an optical path, is embedded in the optical path of an optical fiber or optical waveguide having a light axis. The isolator has a slot extending across the light axis in a direction slanted with respect to the light axis. The optical element is inserted in the slot and the spaces between the optical element and the incoming and outgoing sides of the slot are filled with an optical adhesive portion. At least one of the interfaces is inclined at an angle reversely from the plane normal to the light axis as viewed from the slanted incoming side of the slot.

Abstract: An optical module controls its output characteristics electrically and an optical switch constitutes the optical module. An optical waveguide circuit (PLC) and an electronic circuit (IC) for driving the PLC are mounted on the same substrate. The IC is composed of a bare chip to be molded afterward. Wiring of the IC is grouped and integrated on the PLC substrate to achieve higher density and miniaturization of the optical module.

Abstract: A radial type light-guiding plate comprises a light source, a light-guiding plate, and a reflective component. The top face of the light-guiding plate is a light output face, and the bottom face thereof is a reflective face. The light source is disposed at sides of the light-guiding plate. The reflective face has channels, which radiate toward the sides near the light source. Because the channels are radial, the reflected light rays in the range of the light-guiding plate near the light source will be less. The light emission near the light source thus will not be too bright. Because the channels of the light-guiding plate that are far from the light source are closer together, light rays can be effectively transmitted thereto to increase the brightness of light emission therefrom, hence letting the brightness of the whole light output face be more uniform.

Abstract: A standard CMOS process is used to fabricate optical, optoelectronic and electronic devices at the same time on a monolithic integrated circuit. FIG. 6 shows a polysilicon and silicon dioxide light scattering element formed on a silicon waveguide. The polysilicon light scatterer is formed on the core of the waveguide with a silicon dioxide layer between the polysilicon and the core. A standard CMOS process is used to form the waveguide and the light scattering element. FIG. 6A is a table summarizing the elements of the light scatterer and the waveguide of FIG. 6 and the CMOS transistors of FIGS. 1 and 2, which are formed from the same materials at the same time on the same substrate. Forming multiple light scatterers on the core of a waveguide can make a grating coupler.

Abstract: A method for making an optical structure and a multilayer optical structure provided with optical guide elements for transmitting at least a light wave, comprises: providing a substrate with a first and second layer; etching out in the second electrically conducting layer a groove having two opposite ends and partly enclosing a first zone of the layer; filling the groove with electrically insulating material; etching out a cavity in the second layer then in the first non-electrically conducting layer partly enclosing a second zone of the second layer, adjacent to or extending the first zone wherein emerges the groove; the cavity comprises a clearance in the second layer; such that the closed part of the second layer corresponding to the zones is electrically isolated from the rest of the layer and the cleared part beneath the second zone constitutes a beam.