Abstract:
An electro-holographic light field generator device comprises surface acoustic wave (SAW) optical modulators arranged in different directions. Specifically, some embodiments have SAW modulators arranged in pairs, nose-to-nose with each other, and have output couplers that provide face-fire light emission. These SAW modulators also possibly include SAW sense transducers and/or viscoelastic surface material to reduce crosstalk.
Abstract:
A directional waveguide-based pixel for use in a mutliview display screen is disclosed. The directional waveguide-based pixel has a liquid crystal layer interposed between the waveguide layer and a substrate layer. The waveguide layer has a waveguide and a patterned grating to scatter an input light beam into a plurality of directional light beams, each directional light beam having a direction and angular spread controlled by characteristics of the patterned grating. An active matrix with individually addressable electrodes may be integrated in the substrate layer or in the waveguide layer to modulate the directional light beams.
Abstract:
An electro-holographic light field generator device comprises surface acoustic wave (SAW) optical modulators arranged in different directions. Specifically, some embodiments have SAW modulators arranged in pairs, nose-to-nose with each other, and have output couplers that provide face-fire light emission. These SAW modulators also possibly include SAW sense transducers and/or viscoelastic surface material to reduce crosstalk.
Abstract:
The invention relates to a tunable resonant grating filter that can reflect optical radiation at a resonant wavelength, said resonant wavelength being selectively variable. The filter comprises a diffraction grating (3), a planar waveguide (4) and a light transmissive material having a selectively variable refractive index to permit tuning of the filter, said light transmissive material forming a tunable cladding layer (5) for the waveguide, preferably a liquid crystal (LC) material. The diffraction grating (3) is placed on the opposite side of the tunable layer (5) with respect to the planar waveguide (4) thereby making possible to tailor the grating structural parameters to the desired bandwidth of the filter response without significantly affecting the tunability of the filter. Within the resonant structure (1) of the present invention, the core layer, i.e., the waveguide (4), can be placed close to the tunable layer (5), either in direct contact with the tunable layer or with an interposed relatively thin intermediate layer(s) between the core and the tunable layer. Proximity of the core layer (4) to the tunable layer (5) implies that the propagation mode can significantly extend into the tunable layer (5) so that the effective refractive index of the fundamental mode in the waveguide (4) is efficiently affected by variations of the refractive index of the tunable layer (5).
Abstract:
A high-performance electro-optic intensity modulator using two polymeric waveguides (22 and 24) having a high extinction-ratio modulation process is implemented by the coupling-out effect of induced grating modulation. The upper modulating electrode (32) has a grating pattern overlapping an edge of the coupling-out waveguide (24) along its length. The two waveguides can be either single-mode or multi-mode, even highly multimode. The inducing of a modulated grating-coupler in a waveguide channel makes the coupling between two waveguides become unidirectional and the coupling efficiency can be achieved to a very high value in theory. The two waveguide channels in this intensity modulator may have large dimensions, so the device can support either single-mode or multi-mode operation. The electro-optic waveguide intensity modulator may be used either as a single optical modulator/switch or as a waveguide modulator/switch array for fiber-optic communication. The modulator can also be implemented in an electro-optic crystal such as LiNbO3. The polymeric waveguide intensity modulator may be thermo-optically modulated.