摘要:
The present invention concerns tunable distributed Bragg reflector (DBR) semiconductor lasers, in particular a DBR laser with a branched optical waveguide 5 within which a plurality of differently shaped lasing cavities may be formed, and a method of operation of such a laser. The laser may comprise a phase control section (418), gain section (420, 422), a sampled grating DBR (412) giving a comb-line spectrum and two tunable, chirped DBRs (414, 416) for broadband frequency training and a coupling section (410).
摘要:
A tuneable laser has a gain section bounded at one end by a first reflector in the form of a distributed Bragg reflector adapted to produce a comb of reflective peaks and on the other end by a second Bragg reflector, the second Bragg reflector adapted to reflect at a plurality of wavelengths and being capable of being varied selectively through discrete segments so that one or more segments of the Bragg reflector can be tuned to a lower wavelength to reflect with a segment reflecting at that lower wavelength to enhance the reflectivity at that lower wavelength.
摘要:
An apodised Bragg grating comprises a base grating section formed by a base order periodic pattern of marks and spaces. The Bragg grating further comprises one or more apodised grating sections that are formed by a periodic pattern of marks and spaces, each defined by the base order pattern from which at least some of the marks are missing. The determination of which marks are missing may be performed by combining the base order pattern with a higher order modulation envelope function.
摘要:
A tuneable laser includes a gain section bounded at one end by a first reflector adapted to produce a comb of reflective peaks and on the other end by a second reflector in the form of a plurality of discrete grating units each capable of reflecting at one of the peaks of the comb, and each grating unit having at least two independently actuable electrodes, which when actuated independently one from the other is capable of reducing the reflectivity of the grating unit and in which at least two of the grating units have different pitches.
摘要:
A tuneable laser includes a gain section (50) bounded by two mirrors (51 and 52) at least one mirror being a chirp grating. At least one of the mirrors includes a plurality of selectable electrodes (59 to 65) to enable the grating to be selectively activated to produce a selective reflection at a predetermined wavelength.
摘要:
An industrial control system includes an industrial controller and a programming interface. The industrial controller maintains a control program for interfacing with a controlled process. The programming interface is operable to communicate a transaction to the industrial controller. The transaction includes a plurality of operations for modifying the control program followed by a commit transaction command. The industrial controller is operable to preprocess the plurality of operations, designate the plurality of operations with a pending status, and commit the operations and clear the pending status responsive to receiving the commit transaction command.
摘要:
A method of consolidating genealogy records includes partitioning the records using at least one index file to form one or more partitions, sorting the records in a partition based on a data element in the records, comparing records within a sort range, based on the comparison, identifying same person records, consolidating information in the same person records, receiving a request from a user to view at least a portion of the consolidated information for a particular group of same person records, and sending a file that includes the portion to the user.
摘要:
An apparatus and method for integrated grating feedback and retro-reflection are disclosed herein. An unitary optical element is designed to provide a feedback output at one end and an ancillary output at an opposite end. A desired output wavelength is determined by the geometry and index of refraction of the unitary optical element.
摘要:
The present application is directed to the measurement of the intensity and phase of high speed optical signals. The present application uses a tunable optical local oscillator, an optical coupler, a photodiode and RF electronics. The tunable laser enables successive measurements to be taken across the optical spectrum allowing the system to measure extremely high bandwidth signals. The signal generated by the local oscillator comprises a component at a frequency between two adjacent modes of the periodic optical signal to be measured. The local oscillator and said periodic signal are optically mixed and sent to a photodiode, the measurement of the phase being based on isolating the resulting beat frequencies. This approach offers a significant improvement over existing time resolved approaches which are limited to the bandwidth of the photodiode (˜50 GHz).
摘要:
A method of consolidating genealogy records includes partitioning the records using at least one index file to form one or more partitions, sorting the records in a partition based on a data element in the records, comparing records within a sort range, based on the comparison, identifying same person records, consolidating information in the same person records, receiving a request from a user to view at least a portion of the consolidated information for a particular group of same person records, and sending a file that includes the portion to the user.