Patent ID: 6990276

Claim:
An optical apparatus, comprising a planar optical waveguide having at least one set of diffractive elements, the planar optical waveguide substantially confining in one transverse spatial dimension optical signals propagating in two other spatial dimensions therein, wherein: each diffractive element set routes, between corresponding input and output optical ports with a corresponding impulse response function, a corresponding diffracted portion of an input optical signal propagating in the planar waveguide that is diffracted by the diffractive element set; the input optical signal has an input temporal waveform, the output optical signal has an output temporal waveform, and the output temporal waveform is given by a convolution of the input temporal waveform and the impulse response function; the input optical signal is successively incident on the diffractive elements; and the diffractive elements of the set are arranged so that the corresponding impulse response function comprises one of i) a corresponding reference temporal waveform, or ii) a time-reverse of the corresponding reference temporal waveform.