Abstract: An optical communication system having an optical transmitter and an optical receiver optically coupled via a multi-path fiber. The optical transmitter launches, into the multi-path fiber, an optical transverse-mode-multiplexed (TMM) signal having a plurality of independently modulated components by coupling each independently modulated component into a respective transverse mode of the multi-path fiber. The TMM signal undergoes inter-mode mixing in the multi-path fiber before being received by the optical receiver. The optical receiver processes the received TMM signal to reverse the effects of inter-mode mixing and recover the data carried by each of the independently modulated components.

Abstract: An apparatus includes a DC-to-DC voltage converter. The DC-to-DC voltage converter has a plurality of pairs of outputs and is configured to apply voltages across the pairs of outputs in a time division multiplexed manner.

Abstract: An image projector having one or more broadband lasers designed to reduce the appearance of speckle in the projected image via wavelength diversification. In one embodiment, a broadband laser has an active optical element and a nonlinear optical element, both located inside a laser cavity. The broadband laser generates an output spectrum characterized by a spectral spread of about 10 nm and having a plurality of spectral lines corresponding to different spatial modes of the cavity. Different individual spectral lines effectively produce independent speckle configurations, which become intensity-superimposed in the projected image, thereby causing a corresponding speckle-contrast reduction.

Abstract: As discussed herein, there is presented a visual communication system, a method of conducting two-way visual communication and an apparatus. In one embodiment, the apparatus includes: (1) a lens substrate having a first array of micro lenses on one side thereof, (2) an optical output substrate having a second array of display pixels and (3) an optical input substrate having a third array of image sensors laterally inter-dispersed with respect to display pixels of the first array and positioned to receive light from the micro lenses of the first array.

Abstract: A waveguide-mode (WM) coupler having a plurality of single-mode fibers, each optically coupled to a different respective waveguide mode of a multimode fiber. The coupling optics employed by the WM coupler are scalable and include reflective fiber-tip coatings, polarization beam splitters, phase masks, and quarter-wave plates configured to overlap and/or separate the optical beams corresponding to different waveguide modes of the multimode fiber in a manner that does not cause a significant increase in the optical insertion losses with an increase in the number of optical channels in the WM coupler.

Abstract: According to one embodiment, an image projector has a spatial light modulator (SLM) adapted to modulate illumination from a laser with a spatial pattern such that the modulated illumination projects an image on a viewing screen. The image projector further has an optical diffuser located on an optical path between the laser and the SLM. The laser is adapted to illuminate the SLM through the optical diffuser to create an illuminated area at the SLM. The optical diffuser is adapted to introduce an angular spread into the light transmitted therethrough. The image projector is adapted to move the illuminated area with respect to the SLM to mitigate speckle in the projected image.

Abstract: System including first and second light sources and controller. First light source is configured to generate first light beam of first perceived color. Second light source is configured to generate second light beam of different second perceived color. Controller is configured to direct light from first light beam to an image projector during first time intervals and to direct light from second light beam to an image projector during second time intervals. First light source generates first light beam with first intensity. Second light source generates second light beam with different second intensity. Controller is configured to temporally interleave first and second time intervals such that second time intervals are longer than first time intervals. Method also provided.

Abstract: According to one embodiment, an image projector has a spatial light modulator (SLM) adapted to modulate illumination from a laser with a spatial pattern such that the modulated illumination projects an image on a viewing screen. The image projector further has an optical diffuser located on an optical path between the laser and the SLM. The laser is adapted to illuminate the SLM through the optical diffuser to create an illuminated area at the SLM. The optical diffuser is adapted to introduce an angular spread into the light transmitted therethrough. The image projector is adapted to move the illuminated area with respect to the SLM to mitigate speckle in the projected image.

Abstract: An apparatus includes a reconfigurable spatial light modulator capable of spatially modulating an incident wavefront responsive to an image formed on the modulator. A light source is configured to direct a coherent illumination light beam towards the modulator such that the modulator produces a modulated outgoing light beam therefrom. A filter is configured to spatially filter a light pattern formed by the outgoing light beam on a plane to selectively transmit light from a plurality of diffraction peaks therein.

Abstract: An optical transmitter includes a set of optical waveguides and first, second, and third optical modulators. Output ends of the optical waveguides of the set form a two-dimensional array capable of end-coupling the optical waveguides of the set to a multimode optical fiber in response to the array being located to optically face one end of the multimode optical waveguide. The first optical modulator is optically connected to a first of the optical waveguides of the set, and each of the second and third optical modulators is optically connected to the second and third of the optical waveguides of the set. The set of optical waveguides is configured to provide a coupling matrix of rank three or more between the optical modulators and optical propagation modes in the multimode optical fiber.

Abstract: An optical coupler for coupling a multimode waveguide and two or more other waveguides. In one embodiment, the optical coupler has an optical phase mask disposed between the multimode waveguide and two or more other waveguides. The optical phase mask imposes on the light passing therethrough a spatial phase pattern that causes selective mode-to-waveguide coupling between the multimode waveguide and the other waveguides. The optical coupler can be used, e.g., in transmitters and receivers of optical transverse-mode-multiplexed signals.

Abstract: An optical device for projecting an image is disclosed. In one embodiment, the optical device includes a configurable optical diffuser adapted to produce a diffuse optical beam having a temporally varying pattern of angular divergence. The optical device further includes a plurality of lenslet pairs to shape the diffuse optical beam and a spatial light modulator to spatially modulate the shaped optical beam to project an image.

Abstract: The disclosure provides apparatuses for videoconferencing and a method of operation thereof. In one embodiment, an apparatus includes: (1) a display substrate occupying less than an entirety of a viewing area, (2) an actuator configured to move the display substrate over the viewing area and (3) a camera having a field of view at least partially overlapping the viewing area and configured to capture a camera image through the viewing area.

Abstract: An apparatus includes a state-switchable screen, a video camera, and a video projector. The video camera and projector are located on a side of the screen opposite to the side thereof of a video conference participant. The apparatus is configured to temporally interleave the screen between a substantially transparent state and a diffusive state. In the substantially transparent state, the video projector is configured to be outside of a viewing field of a video conference participant looking toward the video camera.

Abstract: A representative optical receiver of the invention receives an optical transverse-mode-multiplexed (TMM) signal through a multimode fiber that supports a plurality of transverse modes. The optical receiver has a plurality of optical detectors operatively coupled to a digital signal processor configured to process the TMM signal to determine its modal composition. Based on the determined modal composition, the optical receiver demodulates each of the independently modulated components of the TMM signal to recover the data encoded onto the TMM signal at the remote transmitter.

Abstract: An optical communication system having an optical transmitter and an optical receiver optically coupled via a multi-path fiber. The optical transmitter launches, into the multi-path fiber, an optical transverse-mode-multiplexed (TMM) signal having a plurality of independently modulated components by coupling each independently modulated component into a respective transverse mode of the multi-path fiber. The TMM signal undergoes inter-mode mixing in the multi-path fiber before being received by the optical receiver. The optical receiver processes the received TMM signal to reverse the effects of inter-mode mixing and recover the data carried by each of the independently modulated components.

Abstract: A representative embodiment of the invention provides an infrared (IR) imaging system adapted to (i) convert an IR image of an object into mechanical displacements of a plurality of movable plates, (ii) use the mechanical displacements to impart a corresponding spatial phase modulation pattern onto a beam of visible light, and (iii) apply spatial filtering to convert the spatial phase modulation pattern into a visible image of the object.

Abstract: An image projector having one or more broadband lasers designed to reduce the appearance of speckle in the projected image via wavelength diversification. In one embodiment, a broadband laser has an active optical element and a nonlinear optical element, both located inside a laser cavity. The broadband laser generates an output spectrum characterized by a spectral spread of about 10 nm and having a plurality of spectral lines corresponding to different spatial modes of the cavity. Different individual spectral lines effectively produce independent speckle configurations, which become intensity-superimposed in the projected image, thereby causing a corresponding speckle-contrast reduction.

Abstract: A representative embodiment of the invention provides a compact image projector having a light source coupled to a spatial light modulator (SLM). The light source has a substantially planar structure. The overall size of the SLM is dominated by its length and/or width. The projector has an optical arrangement that enables the SLM to be oriented so that the SLM's dominant dimensions are parallel to the plane of the light source. Due to this relative orientation of the SLM and light source, one of the dimensions of the image projector can be smaller than 12 mm, which advantageously enables incorporation of the projector into a hand-held electronic device, such as a cell phone, PDA, or media player.

Abstract: A device employing at least one wavelength sieve/combiner that operates on discrete wavelength units and is optically interposed between an array of fibers and an array of micro mirrors which may be configured to act as in a multiplexing mode, a demultiplexing mode, a broadcast mode, and combinations of such modes. Each wavelength sieve/combiner can split a wavelength division multiplexed (WDM) beam into various discrete wavelength unit beams, combine various discrete wavelength unit beams into a WDM beam, or cause multiple copies of part or all of the wavelengths to be supplied as outputs. Typically, each fiber is associated with one wavelength sieve/combiner. Preferably, the beams between a wavelength sieve/combiner and the micro mirror array should be converging to the plane of the micro mirror array.