Abstract: An optical module is formed by sticking the optical element mounting substrate and the sealing substrate together, then by sealing the stuck body. The optical mounting substrate includes an optical element on its top surface and it is used to guide electrical signals to its back side through a through-via hole provided in itself. The sealing substrate includes a lens at its back side and a recessed part used to hold an optical fiber at its front side.

Abstract: An optical module includes an optical element mount substrate having a laser diode and a photo detector mounted thereon on a straight line in a horizontal direction of the surface of the substrate, a first optical function integrate substrates, provided in its one surface with surfaces tilted at an angle to the parallel surface of the substrate for refracting light propagated in a substrate thickness direction, the two tilted surfaces being arranged to face each other. The photo detector and the first and second optical function integrate substrates are laminated in the substrate thickness direction, a first optical wavelength filter and a reflecting film having different wavelength transmissivities to the propagation light are provided in an optical path between the first and second tilted surfaces.

Abstract: Plural p-n junctions are formed in a waveguide such that they have junction interfaces in a normal direction to a surface of a substrate (to an extending direction of the substrate). Accordingly, a doping concentration changes in only a horizontal direction in the substrate, and it is possible to fabricate using the same processes as those for silicon electronic devices and to perform device fabricating at a low cost. Moreover, two or more junction interfaces are formed in the waveguide and thus an occupied area of the waveguide in a refractive index modulation region expands. Therefore, the efficiency of the refractive index modulation can be improved and a low-voltage operation is possible.

Abstract: The present invention provides: (1) a compensator that compensates a wide range of amount of dispersion of light in a wide bandwidth band; and (2) a variable dispersion slope compensator applicable to the case where a transmission path suitable for a wavelength division multiplexing transmission system produces a wavelength dispersion slope.

Abstract: An optical element mounting substrate where a plurality of light emitting elements have been mounted on the same plane, a lens array for collimating a plurality of light emitted from the plurality of light emitting elements, and a wavelength multiplexing/demultiplexing device are prepared. The wavelength multiplexing/demultiplexing device has typically mounted both a wavelength selecting filter and a mirror on front and rear planes of a transparent substrate. These three components are mounted within a package at a desirable angle position. Optical axes of respective wavelengths of the wavelength multiplexing/demultiplexing device are determined based upon a thickness and an angle of the light emitting element mounting substrate, and are arrayed on a straight line of a horizontal plane. As a consequence, if the respective light emitting elements are arranged on the optical axes which are exclusively determined by a design work, then optical multiplexing/demultiplexing operations can be carried out.

Abstract: An optical module comprising: a submount provided on a CAN stem; light-emitting device and a light-receiving device; a CAN cap or package; and an optical multiplexer/demultiplexer having a wavelength selective filter on a substrate that has transmissivity to passing light and a mirror, where an extending direction of the optical multiplexer/demultiplexer is fixed in the CAN cap or the package being tilted by an angle ? (??2N?, N=0, 1, 2, . . . ) in a two-dimensional cross section with respect to one surface of an optical device mounting board, outgoing light from the light-emitting device passes through the wavelength selective filter and the substrate and enters an optical fiber outside the cap, and outgoing light from the optical fiber enters the optical multiplexer/demultiplexer and is reflected by the wavelength selective filter and further reflected by the mirror, and then exits the optical multiplexer/demultiplexer to enter the light-receiving device.

Abstract: An optical module includes an optical element mount substrate having a laser diode and a photo detector mounted thereon on a straight line in a horizontal direction of the surface of the substrate, a first optical function integrate substrates, provided in its one surface with surfaces tilted at an angle to the parallel surface of the substrate for refracting light propagated in a substrate thickness direction, the two tilted surfaces being arranged to face each other. The photo detector and the first and second optical function integrate substrates are laminated in the substrate thickness direction, a first optical wavelength filter and a reflecting film having different wavelength transmissivities to the propagation light are provided in an optical path between the first and second tilted surfaces.

Abstract: The present invention provides an ultra-mini and low cost refractive index measuring device applicable to biochemical measurements of an extremely minute amount of a sample. The refractive index measuring device uses a photonic crystal without any requirement of an external spectrograph or the like. The micro sensor device according to the present invention includes a light source emitting light with a single wavelength, a microcavity in which a resonant wavelength varies depending on a position thereof. A refractive index of a material to be measured is measured based on positional information by detecting a transmitting position of light changing in response to a change of a refractive index of the measured material. The micro sensor device according to the present invention enables measurement of a refractive index of a material to be measured without using a large-scale spectrograph.

Abstract: A core of an optical waveguide and a core of a waveguide type optical device are adjacently disposed, and a layer is continuously formed at one end of the core of the waveguide type optical device, wherein an effective refractive index of the layer decreases toward a long axis direction of the optical waveguide stripe.

Abstract: The present invention provides: (1) a compensator that compensates a wide range of amount of dispersion of light in a wide bandwidth band; and (2) a variable dispersion slope compensator applicable to the case where a transmission path suitable for a wavelength division multiplexing transmission system produces a wavelength dispersion slope. The present invention realizes: (1) a variable dispersion compensator that compensates a wide range of amount of dispersion of light in a wide bandwidth band; and (2) a variable dispersion slope compensator suitable for a wavelength division multiplexing transmission system. To realize the above, a dispersion compensating unit is provided with a structure in which a mirror is disposed in parallel to or with a slight angle relative to an etalon to reflect a light beam emitted from a collimator on the etalon multiple times and then emit the light beam into another collimator.

Abstract: The present invention provides an ultra-mini and low cost refractive index measuring device applicable to biochemical measurements of an extremely minute amount of a sample. The refractive index measuring device uses a photonic crystal without any requirement of an external spectrograph or the like. The micro sensor device according to the present invention includes a light source emitting light with a single wavelength, a microcavity in which a resonant wavelength varies depending on a position thereof. A refractive index of a material to be measured is measured based on positional information by detecting a transmitting position of light changing in response to a change of a refractive index of the measured material. The micro sensor device according to the present invention enables measurement of a refractive index of a material to be measured without using a large-scale spectrograph.

Abstract: A micro-spectroscopic measuring device having a structure in which a spectroscopic element made of an array of photonic crystals with defects, flow paths for introducing a sample, and light detecting elements with sensitivity to a band from near infrared to infrared are stacked.

Abstract: The invention provides an optical waveguide for enabling the reduction of a coupling loss caused by difference in the size of a mode field diameter between optical waveguide modes different in the mode field diameter and a coupling loss caused by reflection on a boundary caused by the difference of media and an optical device using it. Structure provided with a mode field diameter converter provided with an antireflection part required to reduce a coupling loss between a microoptical circuit and a single mode optical fiber is integrally produced using effective refractive index control based upon photonic crystal structure.

Abstract: A micro-spectroscopic measuring device having a structure in which a spectroscopic element made of an array of photonic crystals with defects, flow paths for introducing a sample, and light detecting elements with sensitivity to a band from near infrared to infrared are stacked.

Abstract: The present invention aims to provide a dispersion compensator which is ultra small in size and low in cost and capable of controlling dispersion compensating values, and an optical transmission system using the dispersion compensator. A dispersion property of light that propagates through defects in a photonic crystal, is used to compensate for each wavelength dispersion. A dispersion compensator comprises a dispersion-compensating-waveguide array in which a plurality of dispersion compensating waveguides having dispersion compensating values different from one another are placed, a drive unit for driving the dispersion-compensating-waveguide array, and optical fibers for inputting/outputting a light signal. Each of the dispersion compensating waveguides comprises regular waveguides and a waveguide made of defects in photonic crystal. The lengths of the waveguides made of the defects in photonic crystal are changed one by one to make dispersion compensating values different from one another.

Abstract: The invention provides an optical waveguide for enabling the reduction of a coupling loss caused by difference in the size of a mode field diameter between optical waveguide modes different in the mode field diameter and a coupling loss caused by reflection on a boundary caused by the difference of media and an optical device using it. Structure provided with a mode field diameter converter provided with an antireflection part required to reduce a coupling loss between a microoptical circuit and a single mode optical fiber is integrally produced using effective refractive index control based upon photonic crystal structure.

Abstract: A photonic crystal has a relatively simple configuration and exhibits a sufficiently large refractive index change. An optical functional device uses the photonic crystal, and a process fabricates such an optical functional device. The photonic crystal includes at least one polymer as a material and changes in refractive index by changing the temperature of the polymer to thereby control the band structure of the photonic crystal. For example, a polymer is charged into holes arranged in a two-dimensional photonic crystal and is heated using a thin-film heater or is cooled using a Peltier device. The temperature is controlled by a temperature controller.

Abstract: A semiconductor laser device includes a semiconductor substrate, a first cladding region on one side of the semiconductor substrate, an active layer region, and a second cladding region disposed on an opposite side of the semiconductor substrate. The active layer region is disposed between the semiconductor substrate and the second cladding region. A first semiconductor region is provided on either side of the active layer region in parallel with a traveling direction of light in the active layer region and has an electric resistance higher than that of the active layer region and a refractive index higher than that of the semiconductor substrate. An insulative or semi-insulative second semiconductor region is formed between the first semiconductor region and part of the second cladding region. A first electrode and a second electrode are provided for injecting a current into the active layer region.

Abstract: The present invention aims to provide a dispersion compensator which is ultra small in size and low in cost and capable of controlling dispersion compensating values, and an optical transmission system using the dispersion compensator.

Abstract: An object of the technique of the present invention disclosed is to provide semiconductor laser devices and semiconductor laser array devices that can ensure high-precision oscillation wavelengths. Another object of the present invention is to provide semiconductor laser devices and semiconductor laser array devices that are less affected by the atmospheric temperature while ensuring high-precision oscillation wavelengths.