Abstract: A system and method for precisely controlling the wavelength selective function provided by fiber Bragg gratings in optical fiber elements. The system and method exploits a wavelength-locked loop servo-control circuit and methodology that enables real time adjustment of the grating pattern being written to said fiber optical link element by a grating writing source to thereby mutually align a center wavelength of the peaked wavelength selective function resulting from the grating pattern with a center wavelength of the optical signal transmitted over a communication channel provided by the fiber. A real-time adaptive dispersion compensation technique for optical fibers is additionally provided that exploits the wavelength-locked loop servo-control circuit.
Type:
Grant
Filed:
October 12, 2001
Date of Patent:
July 22, 2003
Assignee:
International Business Machines Corporation
Inventors:
Lawrence Jacobowitz, Casimer Maurice DeCusatis
Abstract: An improved wavelength division multiplexing device is disclosed. The improved wavelength division multiplexing device has a diffraction grating for combining a plurality of monochromatic optical beams into a multiplexed, polychromatic optical beam. The improvement in the improved wavelength division multiplexing device is the use of a homogeneous refractive index collimating/focusing lens for collimating the plurality of monochromatic optical beams traveling along a first direction to the diffraction grating, and for focusing the multiplexed, polychromatic optical beam traveling along a second direction from the diffraction grating, wherein the second direction being substantially opposite the first direction.
Abstract: Direct space-to-time pulse shaping and optical pulse train generation is achieved in the present invention which features an optical transmitter that includes: an input port receiving a pulsed light beam; a planar modulator coupled to said input port to spatially pattern the beam; a spectral disperser receiving the patterned beam to spectrally disperse and direct the patterned beam; a focus element receiving the dispersed beam and producing a focused beam; and an output port having an aperture positioned to receive a portion of the focused beam.
Abstract: An optical fiber transmission system includes an optical transmitter for generating light; a dispersive optical fiber link optically coupled to the optical transmitter, for transmitting the light generated by the optical transmitter; and a chirped optical fiber grating, optically coupled to the optical transmitter and to the dispersive optical fiber link, for providing at least a partial dispersion compensation to the light generated by the optical transmitter, before the light is transmitted in the dispersive optical fiber link; the chirped optical fiber grating including a polarization-maintaining optical fiber having a chirped refractive index variation
Abstract: An optical isolator includes a first optical collimator, a first birefringent crystal, a Faraday rotator, a second birefringent crystal and a second optical collimator. The first and second collimators have the same structure and configuration. Each first and second collimator includes a ferrule, an optical fiber retained in the ferrule, and a collimating lens, all of which are secured in a tube. The first and second birefringent crystals are respectively fixed to the first and the second collimators. The Faraday rotator is stationed between the first and second collimators, and fixed onto an end of the first collimator. In assembly, the first and second collimators and the Faraday rotator are all secured in a stainless steel outer tube. The second collimator is rotated within the outer tube until correct relative alignment of optical axes of the birefringent crystals is attained.
Type:
Grant
Filed:
October 17, 2001
Date of Patent:
April 29, 2003
Assignee:
Hon Hai Precision Ind. Co., Ltd.
Inventors:
Ja Jn Dy, Chun Yu Lee, Tai-Cheng Yu, Chien-Cheng Chen
Abstract: Fiber optical devices formed on substrates fabricated with grooves that operate based on evanescent optical coupling through a side-polished fiber surface in each fiber involved. The fiber cladding under the side-polished fiber surface is designed to support a radial mode profile wider than a radial mode profile supported by adjacent fiber portions.