Abstract: A real-time optical compensating apparatus reduces the PMD in an optical fiber by determining the principal states of polarization of the optical fiber and delaying one principal state of polarization with respect to the other.

Abstract: A method and apparatus are provided for generating short (e.g., picosecond) pulses using a 2 section 1553 nm DBR laser without gain switching nor external modulation. The center wavelength of the DBR section is modulated at 0.5 GHz to generate a constant amplitude frequency modulated optical wave Large group velocity dispersion is then applied with a chirped fiber Bragg grating to convert the FM signal to a pulse stream.

Abstract: A parallel monitored and controlled optical PMD compensator comprises a branch optical signal split from an optical signal path. A polarization controller (PC) and differential group delay are disposed in each of the paths. A controller adjusts polarization compensation of the PCs in response to PMD dispersion of the branch optical signal. A PMD monitor is preferably disposed in the branch path providing a monitor signal to the controller for use in adjusting the PCs. A polarization rotator may inject a reference signal into the paths with the PC disposed in the branch path acting as a polarization scrambler. A state of polarization (SOP) of the reference signal may be monitored by polarimeters disposed in both paths and the SOP of the reference signal in the branch path may be provided to the controller for adjusting polarization compensation of the inline PC.

Abstract: A real-time optical compensating apparatus reduces the PMD in an optical fiber by determining the principal states of polarization of the optical fiber and delaying one principal state of polarization with respect to the other.

Abstract: A real-time optical compensating apparatus reduces the PMD in an optical fiber by determining the principal states of polarization of the optical fiber and delaying one principal state of polarization with respect to the other.

Abstract: A method and apparatus are provided for generating short (e.g., picosecond) pulses using a 2 section 1553 nm DBR laser without gain switching nor external modulation. The center wavelength of the DBR section is modulated at 0.5 GHz to generate a constant amplitude frequency modulated optical wave Large group velocity dispersion is then applied with a chirped fiber Bragg grating to convert the FM signal to a pulse stream.

Abstract: A method and an apparatus for stretching an optical pulse and shaping its spectrum. The method includes the step of: providing a an optical fiber element having a first long length fiber Bragg grating having a refractive index perturbation of varying periodicity. The optical pulse is launched into the fiber Bragg grating, wherein the Bragg grating reflects the pulse in a chromatically dispersed output. The reflected output is coupled with an optical modulator programmed to temporally modify the amplitude of the chromatically dispersed output to attenuate selected optical frequencies in a desired pattern. The apparatus for stretching and arbitrarily shaping the spectrum of an optical pulse with a desired wavelength resolution &Dgr;&lgr;res includes a routing optical device and an optical fiber element having a Bragg grating. The routing optical device routs energy between different waveguides, and has an input port to receive the optical pulse.

Abstract: A polarization compensated waveguide grating router is formed by reducing the thickness of the cladding material deposited over segments of waveguide cores to be on the order of the height of the vertical extension of the optical field of the waveguide. The resulting "air-patch" segments increase the birefringence in the patch segments of the waveguides. By using an air-patch length which is inversely proportional to the length of each waveguide, the correct phase relationship can be maintained between the different waveguides to produce an InP-based router which is polarization independent.