摘要:
An optical fibre distributed feedback laser comprises an amplifying optical fibre (50) operable to provide optical gain at a lasing wavelength, in which a diffraction grating (30) is disposed on at least a portion of the amplifying optical fibre to provide distributed optical feedback for sustaining lasing action at the lasing wavelength.
摘要:
Consistent with the present invention, a tunable laser emits a monitoring signal which is combined with the WDM channels typically at the transmit side of a WDM system. At each monitoring point along the WDM system, the WDM channels are filtered out, the monitoring signal is sensed, and desired systems parameters (e.g., gain flatness, dispersion, PMD and OSNR) are measured. Accordingly, a single tunable element, i.e., the tunable laser, can be provided, thereby reducing costs. Moreover, system performance can be ascertained regardless of whether WDM channels are present.
摘要:
A dual-band optical filter is disclosed which has two transmission bands. The first band is relatively narrow (about 1 nm) and encompasses a wavelength of about 1550 nm, while the second band is relatively broad (greater than 50 nm) to transmit wavelengths in a range of 1300-1400 nm. Accordingly, the filter can be used in wavelength division multiplexed communication systems to simultaneously select a payload channel having a wavelength of approximately 1550 nm, and a 1310 nm service channel.