Abstract:
An optical coupler for coupling optical-pump power into a multimode fiber configured to transport an optical space-division-multiplexed (SDM) signal, the coupling being performed in a manner that enables amplification of the SDM signal in the multimode fiber via a stimulated-emission process or a stimulated Raman- scattering process. The optical coupler can be a part of an optical transmitter configured for co-directional pumping, an optical receiver configured for contra- directional pumping, or a relay station disposed within an optical communication link and configured for either type of pumping. The optical coupler can advantageously be used, e.g., to offset the different degrees of attenuation to which the SDM-signal components corresponding to different guided modes of the multimode fiber are subjected to 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 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:
An apparatus includes a first optical mode coupler having a spatial light modulator with a two-dimensional array of separately controllable optical phase modulators. The optical mode coupler is configurable to cause the spatial light modulator to couple a light source or light detector to an end-face of a multi-mode optical fiber via a plurality of light beams. Each of the light beams couples to a different one of optical modes in the multi- mode optical fiber.
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 representative embodiment of the invention provides an infrared (IR) imaging system (300) adapted to (i) convert an IR image of an object into mechanical displacements of a plurality of movable plates (304,306), (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:
A terminal comprises a display substrate and an actuator configured to move the display substrate in a cyclic movement over a viewing area. A proximity sensor is configured to generate detection signals. An image controller, configured to receive the detection signal, calculates a cycle time of the cyclic movement of the display substrate and controls at least one of a transmission rate of the display data to the display substrate and the movement of the display substrate caused by the actuator.
Abstract:
A feed-forward equalizer can be used in the host optical receiver to perform at least some of the desired signal processing in the optical domain, e.g., prior to coherently detecting and digitizing the received optical signal(s). In some embodiments, the signal processing implemented in the feed-forward equalizer can at least partially compensate the adverse effects of chromatic dispersion, polarization-mode dispersion, and/or spatial-mode mixing/crosstalk imparted on the received optical signal(s) in the optical transport link. This reduces the signal-processing load of and the signal-processing requirements to the receiver's electrical DSP.