Patent ID: 6344913
Filing Date: 2002-02-05
Classification: G02F,H01S,H04J,H04L

Abstract:
A method of deriving a clock signal at a divided clock rate from an optical signal stream at a higher clock rate, the stream comprising a sequence of pulses having a given bit period, the method comprising:(a) applying the optical signal stream to an input port of a single-stage all-optical non-linear gate, which gate includes a non-linear element; (b) feeding back an optical signal from an output of the said single-stage all-optical non-linear gate, via a control input of said gate to said non-linear element, the transit time between the input port and the control input being an integer multiple of the bit period and the optical signal from the output of said gate remaining in the optical domain as the optical signal is fed back to said non-linear element; and (c) outputting an optical signal at a divided clock rate from the single-stage all-optical non-linear optical gate.