Abstract: An optical grating comprising a grating layer and two surface layers, the layers being arranged with the grating layer between the surface layers. The grating layer comprises a set of multiple, discrete, elongated first grating regions that comprise a first dielectric material and are arranged with intervening elongated second grating regions. The bulk refractive index of the dielectric material of the first grating regions is larger than the bulk refractive index of the second grating regions. The first surface layer comprises a first impedance matching layer, and the second surface layer comprises either (i) a second impedance matching layer or (ii) a reflective layer. Each said impedance matching layer is arranged to reduce reflection of an optical signal transmitted through the corresponding surface of the grating layer, relative to reflection of the optical signal in the absence of said impedance matching layer.

Abstract: A first article has a surface bearing a diffraction grating that comprises a plurality of elevated regions and recessed regions and a reflective coating that provides reflective diffraction within the article but is sufficiently thick to prevent diffraction outside the article. Alternatively, the reflective coating can be arranged to also provide reflective diffraction outside the article. A second article has a surface bearing a diffraction grating that comprises a plurality of elevated regions and recessed regions. Either (i) at least a portion of each ridge, or (ii) at least portion of each trench, comprises a material differing with respect to its refractive index or with respect to its optical transmissivity.

Abstract: A packaging article comprises first and second packaging members with one or more depressions and corresponding protrusions, respectively, and can be assembled with their each protrusion received within the corresponding depression. A transverse cross section of each depression is concave. A transverse cross section of each protrusion includes a secondary protrusion that forms a longitudinal ridge; a longitudinal cross section of the ridge comprises one or more concavities. A substantially rectangular object is place in a depression and the first and second packaging members are assembled. The object, received within the depression and located between the assembled packaging members, rests with two opposing edges of the object urged against the concave surface of the depression with corresponding lines of contact oriented substantially longitudinally, and with two other opposing edges of the object urged against the concavity.

Abstract: An article comprises a volume of material having at least one faceted or curved surface, and at least one diffraction grating on at least one surface of the article. The diffraction grating comprises a set of diffractive elements formed in a deformable layer attached to the surface of the article. A method comprises forming the set of diffractive elements by deformation of the deformable layer, and attaching the deformable layer to a surface of the article. The layer can be deformed to form the diffractive elements before or after it is attached to the surface of the article.

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 comprises at least one primary diffraction grating and at least one reference diffraction grating each formed on or within a common grating substrate. The reference diffraction grating is arranged so as to diffract and disperse spatially according to wavelength a reference optical signal incident on the reference diffraction grating at an input incidence angle. The primary diffraction grating is arranged so as to diffract and disperse spatially according to wavelength an input optical signal incident on the primary diffraction grating at the input incidence angle. The reference and primary diffraction gratings exhibit at least one differing grating structural parameter. The reference and primary diffraction gratings are arranged so that a diffracted and spatially dispersed reference optical signal having at least one known wavelength component defines at least one spatial wavelength calibration reference for the diffracted and spatially dispersed input optical signal.

Abstract: An optical grating comprising a grating layer and two surface layers, the layers being arranged with the grating layer between the surface layers. The grating layer comprises a set of multiple, discrete, elongated first grating regions that comprise a first dielectric material and are arranged with intervening elongated second grating regions. The bulk refractive index of the dielectric material of the first grating regions is larger than the bulk refractive index of the second grating regions. The first surface layer comprises a first impedance matching layer, and the second surface layer comprises either (i) a second impedance matching layer or (ii) a reflective layer. Each said impedance matching layer is arranged to reduce reflection of an optical signal transmitted through the corresponding surface of the grating layer, relative to reflection of the optical signal in the absence of said impedance matching layer.

Abstract: A method comprises computing an interference pattern between a simulated design input optical signal and a simulated design output optical signal, and computationally deriving an arrangement of at least one diffractive element set from the computed interference pattern. The interference pattern is computed in a transmission grating region, with the input and output optical signals each propagating through the transmission grating region as substantially unconfined optical beams. The arrangement of diffractive element set is computationally derived so that when the diffractive element set thus arranged is formed in or on a transmission grating, each diffractive element set would route, between corresponding input and output optical ports, a corresponding diffracted portion of an input optical signal incident on and transmitted by the transmission grating. The method can further comprise forming the set of diffractive elements in or on the transmission grating according to the derived arrangement.

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 comprises a set of diffractive elements on a substrate. They are arranged: (i) to receive an input signal propagating from an input port as a diffraction-guided optical beam, (ii) to diffract a portion of the received input signal as an output signal, (iii) to route the output signal to propagate to an output port as a diffraction-guided optical beam, and (iv) to exhibit a positional variation in diffractive amplitude, optical separation, or spatial phase over some portion of the set. The arrangement of the diffractive elements corresponds to an interference pattern derived from computed interference at a surface of the substrate between a simulated design input and output optical signals. Each diffractive element comprises at least one trench segment positioned along a path defined by a constant-phase contour of the interference pattern. Each trench segment is substantially rectangular or trapezoidal in transverse cross section.

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: 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: A near-to-eye display system for forming an image as an illuminated region on a retina of at least one eye of a user is disclosed. The system includes a source of modulated light, a proximal optic positionable adjacent an eye of the user to receive the modulated light. The proximal optic has a plurality of groups of optically redirecting regions. The optically redirecting regions are configured to direct a plurality of beams of the modulated light into a pupil of the eye to form a contiguous illuminated portion of the retina of the eye. A first group of the optically redirecting regions is configured to receive modulated light from the source and redirect beams of the modulated light into the pupil of the eye for illumination of a first portion of the retina. A second group of the optically redirecting regions is configured to receive modulated light from the source and redirect beams of the modulated light into the pupil of the eye for illumination of a second portion of the retina.

Abstract: An optical apparatus comprises an optical interconnect structure defining one or more optical source and receiver ports and one or more interconnect optical signal pathways connecting corresponding optical signal source and receiver ports. The optical interconnect structure comprises an optical waveguide defining a portion of each interconnect optical signal pathway. Each interconnect pathway includes a wavefront diffractive transformation region and a corresponding set of diffractive elements thereof. Each diffractive element set diffractively transforms a corresponding diffracted portion of an incident signal with a corresponding design input signal wavefront into an emergent signal with a corresponding design output signal wavefront. For at least one diffractive element set, only one of the corresponding design input or output signal wavefronts is confined in at least one transverse dimension by the optical waveguide, while the other design wavefront propagates without confinement by the optical waveguide.

Abstract: A slab optical waveguide confines in one transverse dimension optical signals propagating in two dimensions therein, and has a set of diffractive elements collectively arranged so as to exhibit positional variation in amplitude, optical separation, or spatial phase. The diffractive elements are collectively arranged so as to apply a transfer function to an input optical signal to produce an output optical signal. The transfer function is determined at least in part by said positional variation in amplitude, optical separation, or spatial phase. The waveguide and diffractive elements are arranged so as to confine only one of the input and output optical signals to propagate in the waveguide so that the optical signal thus confined is successively incident on the diffractive elements, while the other optical signal propagates unconfined by the waveguide in a direction having a substantial component along the confined dimension of the waveguide.

Abstract: An optical time delay apparatus comprises: a multi-wavelength optical source; a diffractive element set imparting a wavelength-dependent delay on signals routed from the source to a 1×N optical switch; and N diffractive element sets routing signals from the 1×N switch to an output port. The optical propagation delay between the source and the output port varies according to the operational state of the source and the 1×N switch. A photodetector may receive the time-delayed signal at the output port.

Abstract: A planar optical waveguide is formed having sets of locking diffractive elements and means for routing optical signals. Lasers are positioned to launch signals into the planar waveguide that are successively incident on elements of the locking diffractive element sets, which route fractions of the signals back to the lasers as locking feedback signals. The routing means route between lasers and output port(s) portions of those fractions of signals transmitted by locking diffractive element sets. Locking diffractive element sets may be formed in channel waveguides formed in the planar waveguide, or in slab waveguide region(s) of the planar waveguide. Multiple routing means may comprise routing diffractive element sets formed in a slab waveguide region of the planar waveguide, or may comprise an arrayed waveguide grating formed in the planar waveguide. The apparatus may comprise a multiple-wavelength optical source.

Abstract: An optical apparatus comprises a planar optical waveguide having at least one set of diffractive elements and confining in at least one transverse spatial dimension optical signals propagating therein. Each diffractive element set routes, between corresponding input and output optical ports, a corresponding diffracted portion of an input optical signal propagating in the waveguide that is successively incident on the diffractive elements and is diffracted by the diffractive element set. The optical signals propagate in the waveguide in corresponding diffractive-region optical transverse modes in regions where the diffractive elements are present, and in corresponding non-diffractive-region optical transverse modes in regions where the diffractive elements are absent.

Abstract: A reconfigurable add-drop multiplexer (R-OADM) comprises an array of channel waveguides coupling two groups of diffractive element sets on a slab waveguide. The channel waveguides include switchable reflectors or are coupled to other channel waveguides by optical switches. Switching a reflector to reflect or setting a switch to couple two waveguides results in a corresponding wavelength channel being added or dropped. Switching the reflector to transmit or setting the switch to uncouple the two waveguides allows the corresponding wavelength channel to pass through the R-OADM without being added or dropped.

Abstract: An optical multiplexing device includes an optical element having at least one set of diffractive elements, and an optical reflector. The reflector routes, between first and second optical ports, that portion of an optical signal transmitted by the diffractive element set. The diffractive element set routes, between first and multiplexing optical ports, a portion of the optical signal that is diffracted by the diffractive element set. More complex optical multiplexing functionality(ies) may be achieved using additional sets of diffractive elements, in a common optical element (and possibly overlaid) or in separate optical elements with multiple reflectors. Separate multiplexing devices may be assembled with coupled ports for forming more complex devices. The respective portions of an optical signal transmitted by and reflected/diffracted from the diffractive element set typically differ spectrally.