Patent attributes
An optical apparatus comprises an optical element having at least two sets of diffractive elements, each diffractive element comprising at least one diffracting region thereof. At least one diffractive element set collectively routes, between a corresponding input optical port and a corresponding output optical port, at least a portion of a corresponding optical signal incident on the diffracting regions that is diffracted thereby as it propagates from the corresponding input optical port. The optical element includes at least one spatial region thereof wherein multiple diffracting regions of a first diffractive element set are present and diffracting regions of a second diffractive element set are absent. The diffractive elements of each set, the diffracting regions thereof, and each said spatial region are arranged so as to impart desired spatial characteristics, desired spectral characteristics, or desired temporal characteristics onto the corresponding routed portion of the optical signal.