TUNABLE FIBRE GRATING DISPERSION COMPENSATION DEVICE

摘要

It is known that the deleterious effects of chromatic dispersion in an optical communications system can be overcome by reflecting the optical signal from a chirped Bragg grating. In this invention, the dispersive characteristics of the Bragg grating may be altered by inducing a temperature gradient along the axis of the grating, where this gradient arises due to the absorption of photons from a pump source, and the subsequent emission of phonons. The central wavelength of the Bragg grating may be altered by stretching or compressing the grating, or by varying the ambient temperature surrounding the grating. The device has additional applications in compensation of polarization-mode dispersion, pulse shaping, and pre-chirping of directly modulated lasers.