Abstract: A lossless optical link in an optical transmission system comprises an optical fiber that is configured to produce Raman gain and provide for Raman distributed gain, via one or more pump sources, along the fiber so that, as an end result, the gain experienced by one or more propagating signals in the fiber link is made fairly uniform along the link or at least a portion of the optical link, such as not vary, for example, no more than five dB along the length of the optical fiber. The several embodiments disclosed provide for different optical pump/component architectures to achieve this end result.

Abstract: A vehicle with a plurality of individually addressable light sources, preferably semiconductor laser light sources or light emitting diodes, each of which produce a beam of light, are optically coupled to a fiber optic waveguide. The laser light sources are grouped together preferably at a single location within the vehicle for easy access and conveniently located within the vehicle. Fiber waveguides distally transmits the beams to the optical loads of the vehicle, including the brake lights, taillights, instrumentation lights and turn signals. Each fiber optic waveguide may be a single optical fiber, such as a multimode fiber, having a numerical aperture large enough to receive illumination from a plurality of light sources. In cases where some optical loads require a larger flux or brightness of light, such as vehicular headlights, which may greater than a single optic fiber can transmit, the waveguide may comprise of a bundle of optical fibers.

Abstract: An improved interferometric modulator permits the reduction in size of optical transmitters. In one embodiment, the optical modulator includes amplifiers or attentuators as phase modulators. In another embodiment, two outputs from a combiner are fed to the modulator, thus avoiding the requirement for an input splitter in the modulator. Light passing through the modulator may be both phase-shifted and amplified or attenuated by optical regulator sections located in the modulator. In another embodiment, the transmitter is included as a multiple-wavelength optical communications source, where individual current sources are provided to actuate a number of light sources feeding into the combiner, a processor controls the operation of each light source, and a modulator driver receives a data input signal to be encoded on the output of the source. By combining a number of modulators, a gray scale modulator may be fabricated for producing a gray scale output, rather than a conventional binary level output.

Abstract: An infrared laser diode wireless local area network for communication between spatially dispersed terminals such as computers which may be located in a single room or in adjacent rooms. The lasers may be tuned to emit at varying frequencies for wavelength multiplexing, or a plurality of lasers each having a different output frequency can be connected with each terminal. A receiver connected to each terminal may similarly detect only a single narrow waveband or may detect a plurality of such wavebands. A transceiver may be employed for signal transmission between separate rooms. High speed data modulation of the carrier waves is provided with MOPA or similar lasers, and broad angular dispersion of the output is achieved by such lasers along with dispersive lenses.

Abstract: Optical pumping arrangements are provided for the broadband or multiple wavelength pumping of optical sources. Sources may be based on Raman gain media and may use multiple output couplers to couple out different wavelength ranges. Cascaded Raman resonator (CRR) configurations may also be used. Overlapping resonators at different wavelengths may be configured to share gain media, and may have separate portions in separate optical paths. Attenuation filters may also be used that are matched to the gain profile of a gain medium, to flatten the gain spectrum and allow equalization of gain to different output wavelengths. In one embodiment, polarization maintaining fiber is used to develop resonant conditions at different wavelengths in different polarization states. Wideband output gratings may be substituted for narrowband gratings to provide CRR configurations with a broader output band. Broadband amplification may also be provided by using a laser source operating in coherence collapse.

Abstract: An improved interferometric modulator permits the reduction in size of optical transmitters. In one embodiment, the optical modulator includes amplifiers or attentuators as phase modulators. In another embodiment, two outputs from a combiner are fed to the modulator, thus avoiding the requirement for an input splitter in the modulator. Light passing through the modulator may be both phase-shifted and amplified or attenuated by optical regulator sections located in the modulator. In another embodiment, the transmitter is included as a multiple-wavelength optical communications source, where individual current sources are provided to actuate a number of light sources feeding into the combiner, a processor controls the operation of each light source, and a modulator driver receives a data input signal to be encoded on the output of the source. By combining a number of modulators, a gray scale modulator may be fabricated for producing a gray scale output, rather than a conventional binary level output.

Abstract: Methods are disclosed for forming Group III-arsenide-nitride semiconductor materials. Group III elements are combined with group V elements, including at least nitrogen and arsenic, in concentrations chosen to lattice match commercially available crystalline substrates. Epitaxial growth of these III-V crystals results in direct bandgap materials, which can be used in applications such as light emitting diodes and lasers. Varying the concentrations of the elements in the III-V crystals varies the bandgaps, such that materials emitting light spanning the visible spectra, as well as mid-IR and near-UV emitters, can be created. Conversely, such material can be used to create devices that acquire light and convert the light to electricity, for applications such as full color photodetectors and solar energy collectors. The growth of the III-V crystals can be accomplished by growing thin layers of elements or compounds in sequences that result in the overall lattice match and bandgap desired.

Abstract: Power scaling by multiplexing multiple fiber gain sources with different wavelengths, pulsing or polarization modes of operation is achieved through multiplex combining of the multiple fiber gain sources to provide high power outputs, such as ranging from tens of watts to hundreds of watts, provided on a single mode or multimode fiber.

Abstract: Power scaling by multiplexing multiple fiber gain sources with different wavelengths, pulsing or polarization modes of operation is achieved through multiplex combining of the multiple fiber gain sources to provide high power outputs, such as ranging from tens of watts to hundreds of watts, provided on a single mode or multimode fiber.

Abstract: Power scaling by multiplexing multiple fiber gain sources with different wavelengths, pulsing or polarization modes of operation is achieved through multiplex combining of the multiple fiber gain sources to provide high power outputs, such as ranging from tens of watts to hundreds of watts, provided on a single mode or multimode fiber.

Abstract: A vehicle with a plurality of individually addressable light sources, preferably semiconductor laser light sources or light emitting diodes, each of which produce a beam of light, are optically coupled to a fiber optic waveguide. The laser light sources are grouped together preferably at a single location within the vehicle for easy access and conveniently located within the vehicle. Fiber waveguides distally transmits the beams to the optical loads of the vehicle, including the brake lights, taillights, instrumentation lights and turn signals. Each fiber optic waveguide may be a single optical fiber, such as a multimode fiber, having a numerical aperture large enough to receive illumination from a plurality of light sources. In cases where some optical loads require a larger flux or brightness of light, such as vehicular headlights, which may greater than a single optic fiber can transmit, the waveguide may comprise of a bundle of optical fibers.

Abstract: Methods are disclosed for forming Group III--arsenide-nitride semiconductor materials. Group III elements are combined with group V elements, including at least nitrogen and arsenic, in concentrations chosen to lattice match commercially available crystalline substrates. Epitaxial growth of these III-V crystals results in direct bandgap materials, which can be used in applications such as light emitting diodes and lasers. Varying the concentrations of the elements in the III-V crystals varies the bandgaps, such that materials emitting light spanning the visible spectra, as well as mid-IR and near-UV emitters, can be created. Conversely, such material can be used to create devices that acquire light and convert the light to electricity, for applications such as full color photodetectors and solar energy collectors. The growth of the III-V crystals can be accomplished by growing thin layers of elements or compounds in sequences that result in the overall lattice match and bandgap desired.

Abstract: III-V arsenide-nitride semiconductor are disclosed. Group III elements are combined with group V elements, including at least nitrogen and arsenic, in concentrations chosen to lattice match commercially available crystalline substrates. Epitaxial growth of these III-V crystals results in direct bandgap materials, which can be used in applications such as light emitting diodes and lasers. Varying the concentrations of the elements in the III-V materials varies the bandgaps, such that materials emitting light spanning the visible spectra, as well as mid-IR and near-UV emitters, can be created. Conversely, such material can be used to create devices that acquire light and convert the light to electricity, for applications such as full color photodetectors and solar energy collectors. The growth of the III-V material can be accomplished by growing thin layers of elements or compounds in sequences that result in the overall lattice match and bandgap desired.

Abstract: An infrared laser diode wireless local area network for communication between spatially dispersed terminals such as computers which may be located in a single room or in adjacent rooms. The lasers may be tuned to emit at varying frequencies for wavelength multiplexing, or a plurality of lasers each having a different output frequency can be connected with each terminal. A receiver connected to each terminal may similarly detect only a single narrow waveband or may detect a plurality of such wavebands. A transceiver may be employed for signal transmission between separate rooms. High speed data modulation of the carrier waves is provided with MOPA or similar lasers, and broad angular dispersion of the output is achieved by such lasers along with dispersive lenses.

Abstract: A surface of a compound III-V semiconductor device is passivated and protected, respectively, by treatment with a sulfur-containing or selenium-containing passivation film on the surface followed by the deposit of a GaN, GaP, InGaP, GaAsP, ZnS or ZnSe protection layer. Prior to passivation and deposition of the protective layer, previously formed contact metalizations may be protected with a liftoff film or layer. A low temperature MOCVD process is used to deposit the protection layer so that the integrity of the previously deposited contact metalization is maintained. The preferred range for MOCVD deposition of the protection layer is in the range of about 300.degree. C. to about 450.degree. C. This processing temperature range is within a temperature range where stable contact metalization exists.

Abstract: A method of manufacturing a p-type III-V nitride compound semiconductor utilizing vapor phase epitaxy is carried out in a MOCVD reactor by growing a III-V nitride compound semiconductor in the reactor employing a reaction gas containing a p-type impurity and then annealing in-situ the nitride compound semiconductor to bring about acceptor activation, the annealing carried out at a temperature below the growth temperature of the III-V nitride compound semiconductor during reactor cooldown. A nitrogen (N) reactant or precursor is provided in the reactor during the annealing step which can produce a reactive form of N capable of suppressing surface decomposition and does not produce atomic hydrogen. Also, acceptor activation is achieved through the employment of a cap layer comprising a n-type Group III-V nitride material, e.g., n-GaN, grown on the p-doped Group III-V nitride layer preventing the occurrence of hydrogenation of the underlying p-doped layer during cooldown.

Abstract: A semiconductor gain medium has an optical cavity comprising a multimode region permitting propagation of light with a diverging phase front and a single mode region. An optical cavity is formed by optical feedback within the medium. Preferably, the feedback comprises a combination of a cleaved facet and a grating. The gain medium may be an amplifier or, in addition to the amplifier, may include a resonator cavity, or operate as an unstable resonator.

Abstract: A semiconductor laser having a light amplifying diode heterostructure with a flared gain region in an narrow aperture end whoch may be coupled to a single mode waveguide and a wide output end. A light emitting surface of the heterostructure proximate to the wide end of the flared gain region is partially reflective and combines with an external reflector to form a resonant cavity that is effectively unstable. The intracavity light-emitting surface proximate to the narrow aperture end is antireflection coated. The external reflector may be a planar mirror or a grating reflector. A lens or an optical fiber may couple the aperture end of the flared gain region to the external reflector. Frequency-selective feedback is provided by orienting the grating reflector or providing a prism in the cavity in front of the external planar mirror. Other filtering elements may also be placed in the external cavity.

Abstract: A semiconductor gain medium has an optical cavity comprising a multimode region permitting propagation of light with a diverging phase front and a single mode region. An optical cavity is formed by optical feedback within the medium. Preferably, the feedback comprises a combination of a cleaved facet and a grating. The gain medium may be an amplifier or, in addition to the amplifier, may include a resonator cavity, or operate as an unstable resonator.

Abstract: A semiconductor laser having a light amplifying diode heterostructure with a flared gain region in an external resonant cavity. The flared gain region has a narrow aperture end which may be coupled to a single mode waveguide and a wide output end. A light emitting surface of the heterostructure proximate to the wide end of the flared gain region is partially reflective and combines with an external reflector to form a resonant cavity that is effectively unstable. The intracavity light-emitting surface proximate to the narrow aperture end is antireflection coated. The external reflector may be a planar mirror or a grating reflector. A lens or an optical fiber may couple the aperture end of the flared gain region to the external reflector. Frequency-selective feedback is provided by orienting the grating reflector or providing a prism in the cavity in front of the external planar mirror. Other filtering elements may also be placed in the external cavity.