Abstract: A planar optical waveguide has sets of diffractive elements, each routing between input and output optical ports diffracted portions of an input optical signal. The diffractive elements are arranged so that the impulse response function of the diffractive element set comprises a reference temporal waveform or its time-reverse. A planar optical waveguide has N×M sets of diffractive elements, each routing between corresponding input and output optical ports corresponding diffracted portions of an input optical signal. The N×M diffractive element sets, N×M input optical ports, and N 1×M optical switches enable routing of an input optical signal any of the N input optical sources to any of the M output optical ports based on the operational state of the corresponding 1×M optical switch.

Abstract: A spectral filter comprises a planar optical waveguide having at least one set of diffractive elements. The waveguide confines in one transverse dimension an optical signal propagating in two other dimensions therein. The waveguide supports multiple transverse modes. Each diffractive element set routes, between input and output ports, a diffracted portion of the optical signal propagating in the planar waveguide and diffracted by the diffractive elements. The diffracted portion of the optical signal reaches the output port as a superposition of multiple transverse modes. A multimode optical source may launch the optical signal into the planar waveguide, through the corresponding input optical port, as a superposition of multiple transverse modes. A multimode output waveguide may receive, through the output port, the diffracted portion of the optical signal. Multiple diffractive element sets may route corresponding diffracted portions of optical signal between one or more corresponding input and output ports.

Abstract: An optical apparatus (spectral filter, temporal encoder, or other) comprises a planar optical waveguide having at least one set of diffractive elements. Each diffractive element set routes by diffraction therefrom a portion of the optical signal propagating in the planar waveguide. The planar waveguide includes at least one material having thermo-optic properties chosen so as to yield a designed temperature dependence of spectral and/or temporal characteristics of the diffracted portion of the optical signal. Variations of material refractive indices, physical dimensions, and/or optical mode distributions with temperature may at least partly compensate one another to yield the designed temperature dependence. Optical materials with ?n/?T of various magnitudes and signs may be variously incorporated into the waveguide core and/or cladding.

Abstract: A distributed optical structure comprises a set of diffractive elements. Individual diffractive element transfer functions collectively yield an overall transfer function between entrance and exit ports. Diffractive elements are defined relative to virtual contours and include diffracting region(s) altered to diffract, reflect, and/or scatter incident optical fields (altered index, surface, etc). Element and/or overall set transfer functions (amplitude and/or phase) are determined by: longitudinal and/or angular displacement of diffracting region(s) relative to a virtual contour (facet-displacement grayscale); longitudinal displacement of diffractive elements relative to a virtual contour (element-displacement grayscale); and/or virtual contour(s) lacking a diffractive element (proportional-line-density gray scale).

Abstract: Method and apparatus are disclosed for optical packet decoding, waveform generation and wavelength multiplexing/demultiplexing using a programmed holographic structure. A configurable programmed holographic structure is disclosed. A configurable programmed holographic structure may be dynamically re-configured through the application of control mechanisms which alter operative holographic structures.

Abstract: An optical apparatus comprises an optical element having at least one set of diffractive elements and multiple channel optical waveguides. Diffractive elements of each set are distributed among diffractive element subsets corresponding to each of the multiple channel waveguides. Each diffractive element set routes, between a corresponding pair of optical ports, those corresponding portions of an optical signal propagating within the optical element that are received by multiple channel waveguides and back-diffracted within the receiving channel waveguides by corresponding diffractive element subsets. The channel optical waveguides are arranged so that optical signals propagate through regions of the optical element between the ports and the first ends of the channel waveguides.

Abstract: An optical element is provided with one or more sets of diffractive elements. Individual diffractive element transfer functions collectively yield corresponding overall transfer functions between corresponding entrance and exit ports. Diffractive elements are defined by contours that include diffracting region(s) altered to diffract, reflect, and/or scatter incident optical fields (altered index, surface, etc). Element transfer functions are determined by: fraction of contour filled by diffracting region(s) (partial-fill grayscale); and/or the spatial profile of the diffracting region(s) (profile-based grayscale). Optical elements may be configured: as planar or channel waveguides, with curvilinear diffracting segments; to support three-dimensional propagation with surface areal diffracting segments; as a diffraction grating, with grating groove segments.