摘要 |
PCT No. PCT/GB96/00072 Sec. 371 Date Jul. 23, 1997 Sec. 102(e) Date Jul. 23, 1997 PCT Filed Jan. 16, 1996 PCT Pub. No. WO96/22562 PCT Pub. Date Jul. 25, 1996An optical switch includes a semiconductor gain medium and inputs for an optical control signal applied to the semiconductor gain medium. The switch has a pair of arms (31, 32) arranged in a Mach-Zehnder configuration. A semiconductor gain medium (SOA1, SOA2) is connected in each arm. A fixed phase shifting element PE is also connected in one arm. Control signals are applied to each of the semiconductor gain media. There is a delay between the control signals selected so that a desired one of the optical pulses experiences a differential phase shift and so we switch to a different output of the multiplexer. In one example, the semiconductor gain media are provided by discrete semiconductor devices sandwiched between a pair of planar substrate on which waveguides forming the other components of the switch are formed. The switch may be used for demultiplexing OTDM signals. |