Abstract:
An optical coupling system comprises a prism or diffraction grating coupling element in combination with a film waveguide or the like affording high selectivity and high coupling coefficient. A prism when used has a coated, partially reflective and interference inducing face arranged parallel to the film waveguide along a coupling interval wavelength of the latter. The coated face coating includes a partially transparent mirror layer and an interference film. When a grating coupling element is used, multiple interfering beams ordinarily produced are reduced to one output beam per diffraction order. Light beams may be propagated on one or both sides of the film.
Abstract:
Diffracted leaky optical waves are coupled out of a thin film optical waveguide device having one surface which is periodically thickness-modulated or corrugated to form an optical diffraction grating. The waveguide device is constructed such that the average thickness of the waveguide in the complex refractive index of the waveguide or one of the layers surrounding the waveguide is varied when an external power source applied to the device is varied and thereby, a parameter of the leaky wave in accordance with the variable power source. In one embodiment, the waveguide is made of light amplifying material which is suitably excited to produce lasing action and cause an optical wave to propagate in the waveguide. The variable parameter in this case is the wavelength of the leaky wave, and the leaky wave is always normal to the plane of the diffraction grating. Consequently, a tunable laser is provided. In a second embodiment, no lasing occurs, but instead, an external light source is used to cause an optical wave to propagate in the waveguide. The parameter which is varied is the angle between the leaky wave and the normal to the diffraction grating, the wavelength of the leaky wave remaining constant.
Abstract:
An electro-holographic light field generator device is disclosed. The light field generator device has an optical substrate with a waveguide face and an exit face. One or more surface acoustic wave (SAW) optical modulator devices are included within each light field generator device. The SAW devices each include a light input, a waveguide, and a SAW transducer, all configured for guided mode confinement of input light within the waveguide. A leaky mode deflection of a portion of the waveguided light, or diffractive light, impinges upon the exit face. Multiple output optics at the exit face are configured for developing from each of the output optics a radiated exit light from the diffracted light for at least one of the waveguides. An RF controller is configured to control the SAW devices to develop the radiated exit light as a three-dimensional output light field with horizontal parallax and compatible with observer vertical motion.
Abstract:
An electro-holographic light field generator device is disclosed. The light field generator device has an optical substrate with a waveguide face and an exit face. One or more surface acoustic wave (SAW) optical modulator devices are included within each light field generator device. The SAW devices each include a light input, a waveguide, and a SAW transducer, all configured for guided mode confinement of input light within the waveguide. A leaky mode deflection of a portion of the waveguided light, or diffractive light, impinges upon the exit face. Multiple output optics at the exit face are configured for developing from each of the output optics a radiated exit light from the diffracted light for at least one of the waveguides. An RF controller is configured to control the SAW devices to develop the radiated exit light as a three-dimensional output light field with horizontal parallax and compatible with observer vertical motion.
Abstract:
A high contrast grating optical modulation includes an optical modulator at a front surface of a substrate to modulate received light. The high contrast grating optical modulation further includes a high contrast grating (HCG) lens adjacent to a back surface of the substrate opposite to the front surface to focus incident light onto the optical modulator. The substrate is transparent to operational wavelengths of the focused incident light and the modulated light.
Abstract:
There is provided a wearable display comprising a light source emitting light of a first wavelength; a first SBG device having a front side and a rear side; first and second transparent plates sandwiching said SBG device; independently switchable transparent electrode elements applied to the opposing surfaces of said transparent plates, a means for spatio-temporally modulating light from the light source to provide image light and a means for coupling the image light into the light guide formed by the two transparent plates and the SBG device. The SBG device comprises a multiplicity of selectively switchable grating regions. The SBG device diffracts image into the pupil of an eye.
Abstract:
An electrooptical device is provided comprising at least one substrate(1), at least one pair of electrodes(2) and at least one layer of an electrooptical material. The electrooptical material represents an optically anisotropic thin crystal film(3) and contains molecules having aromatic rings and possessing a lattice with an interplanar spacing (Bragg's reflection) of 3.4 ± 0.2 Å along one of optical axes. The electrooptical material(3) has anisotropic refractive indices and/or anisotropic absorption coefficients that are depended on an electric field strength.
Abstract:
The invention relates to fully light controllable integrated optical devices comprising a protein as a material of non linear optical property, methods for carrying out a simple logical operation using the optical devices of the invention, methods for the preparation of a fully light controllable integrated optical device comprising a protein as a material of non linear optical property, uses of the optical devices as an optically controlled optical switch or as an integrated optical logical element or as an integrated optical sensor. and complex integrated optical modules The invention can be used to the fields of laser technology, optoelectronics and integrated optics.
Abstract:
An asymmetric waveguide pair (1440) with a differential thermal response has an optical coupling frequency that may be thermo-optically tuned. Tuning may also be accomplished by applying an electric field (1445) across a liquid crystal portion (1442) of the waveguide structure. The waveguide pair may include a grating and be used as a frequency selective coupler for an optical resonator. The differential waveguide pair may also be used as a temperature or electric field sensor, or it may be used in a waveguide array to adjust a phase relationship, e.g. in an arrayed waveguide grating.
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).