Optical device.

摘要

An optical device comprises a 50-50 cross-coupler (4) having a pair of ports (10, 12) optically coupled by a waveguide (14) which includes a portion of material (16) having a non-linear refractive index with a relaxation time such that the effect on the non-linear portion (16) of a first pulse passing through the portion last long enough to affect the phase of a second pulse relative to the first. It finds application as a logic element, optical amplifier modulator and the like.