摘要:
A tunable semiconductor laser comprises a gain section having an MQW active region, a uniform pitch grating DFB region, and first waveguide. A composite reflector, including a second MQW region and a second waveguide, forms a cavity resonator with the DFB region. A tuning voltage applied to the composite reflector induces refractive index changes, thereby allowing the center wavelength to be altered. A dither signal applied the composite reflector broadens the spectrum of the laser output, thereby reducing SBS in fiber optic systems
摘要:
A tunable semiconductor laser comprises a gain section having an MQW active region, a uniform pitch grating DFB region, and first waveguide. A composite reflector, including a second MQW region and a second waveguide, forms a cavity resonator with the DFB region. A tuning voltage applied to the composite reflector induces refractive index changes, thereby allowing the center wavelength to be altered. A dither signal applied the composite reflector broadens the spectrum of the laser output, thereby reducing SBS in fiber optic systems
摘要:
A tunable semiconductor laser comprises a gain section having an MQW active region, a uniform pitch grating DFB region, and first waveguide. A composite reflector, including a second MQW region and a second waveguide, forms a cavity resonator with the DFB region. A tuning voltage applied to the composite reflector induces refractive index changes, thereby allowing the center wavelength to be altered. A dither signal applied the composite reflector broadens the spectrum of the laser output, thereby reducing SBS in fiber optic systems.
摘要:
A tunable semiconductor laser comprises a gain section having an MQW active region, a uniform pitch grating DFB region, and first waveguide. A composite reflector, including a second MQW region and a second waveguide, forms a cavity resonator with the DFB region. A voltage applied to the composite reflector induces a quantum confined stark effect, thereby allowing the wavelength to be altered. In one embodiment, the current drive to the active region and the shape of the first waveguide (e.g., a raised-sine function) are mutually adapted so that N longitudinal modes have essentially the same threshold gain and so that the DFB region spanned by the first waveguide is segmented into N zones, each zone providing optical feedback at a different wavelength corresponding to a different longitudinal mode.
摘要:
A tunable semiconductor laser comprises a gain section having an MQW active region, a uniform pitch grating DFB region, and first waveguide. A composite reflector, including a second MQW region and a second waveguide, forms a cavity resonator with the DFB region. A tuning voltage applied to the composite reflector induces a quantum confined stark effect, thereby allowing the center wavelength to be altered. A pre-chirp signal applied the composite reflector reduces signal distortion in fiber optic systems.
摘要:
In a WDM fiber-optic network, a unique laser transmitter enables signals to be routed at three hierarchical levels: at one level discrimination among signal paths is based on N WDM wavelength channels, at another level discrimination is based on m AM subcarrier frequency channels, and at a third level discrimination is based on n FM subcarrier frequency channels. Thus, a total of Nmn distinguishable optical channels can be accommodated and a like number of users served. The laser transmitter comprises a broadband, tunable semiconductor laser which includes an intracavity, integrated composite reflector to which a tuning voltage and a FM dither signal are applied, an intracavity gain section to which drive current is applied, and an extracavity, integrated electroabsorption modulator to which an information (e.g., data, voice, video) signal and an AM dither signal are applied. The tuning voltage provides coarse wavelength tuning among N WDM channels, whereas the FM dither signal produces an additional m channels via FM-SCM. The AM dither likewise produces an additional n channels via AM-SCM.
摘要:
In accordance with the invention a multiwavelength optical fiber cross connect is provided with an active all-fiber optical router for multiplexing/demultiplexing. The router is comprised of one electronic component--a phase controller--and four fiber components: 1) a fiber directional coupler, 2) a fiber reflective grating filter, 3) a fiber tap, and 4) a fiber phase modulator. The application describes how to make optical routers from these components ranging in complexity from a single wavelength drop router to an N-port, N-wavelength router for add/drop multiplexing. The application also describes how optical wavelength routers can be combined to create optical fiber Cross connect (OXCs), ranging in complexity from 2.times.2 single wavelength OXCs to NXN, M-wavelength OXCs.
摘要:
In accordance with the invention a multiwavelength optical fiber transmission system is provided with a passive all-fiber optical router for add/drop multiplexing. The passive router is comprised of three fiber components: 1) a fiber directional coupler, 2) a fiber reflective grating filter and 3) a fiber notch filter. The specification describes optical routers from these components ranging in complexity from a three wavelength router to an N-wavelength router.
摘要:
An optical fiber connector plug includes a housing through which extends a cable containing at least one optical fiber. A ferrule, which is supported by the housing, is provided for receiving the optical fiber. The ferrule has a mating facet and an opposing rear facet located in the housing. The ferrule has at least one guide pin thru-hole and at least one optical fiber thru-hole extending between the mating facet and the opposing rear facet. The guide pin thru-hole has an opening portion extending inward from the mating facet. The opening portion is tapered outward to meet the mating facet in an oblique manner such that the opening portion has a diameter in the plane of the mating facet that is greater than a diameter of a remainder of the guide pin thru-hole.
摘要:
An optical fiber connector plug includes a housing through which extends a cable containing at least one optical fiber. A ferrule, which is supported by the housing, is provided for receiving the optical fiber. The ferrule has a mating facet and an opposing rear facet located in the housing. The ferrule has at least one guide pin thru-hole and at least one optical fiber thru-hole extending between the mating facet and the opposing rear facet. The guide pin thru-hole has an opening portion extending inward from the mating facet. The opening portion is tapered outward to meet the mating facet in an oblique manner such that the opening portion has a diameter in the plane of the mating facet that is greater than a diameter of a remainder of the guide pin thru-hole.