Abstract:
A tunable optical signal device and method of using the same having at least two filter elements, each of said filter elements being made of a material having an adjustable parameter, wherein the adjustable parameter is maintained at slightly different values for adjacent filter elements.
Abstract:
A display device has an insulated basic substrate. A plurality of light waveguides are arranged on the basic substrate in parallel to each other. A plurality of signal wires is arranged in parallel and in a manner to be crossed with the light waveguides, respectively. A plurality of photoconductive layers three-dimensionally are laid between the light waveguides and the signal wires and directly connected with each light guiding portion of the light waveguides at respective crosspoints between the light waveguides and the signal electrodes. A plurality of pixel electrodes provided are to be connected with the photoconductive layers, respectively. An insulated opposed substrate located in opposition to the basic substrate with a display medium therebetween and having an opposed electrode on the surface opposed to the basic substrate. And the relation among an index of refraction n.sub.1 of the light guiding portion, an index of refraction n.sub.2 of the photoconductive layer, and an angle of incidence .theta. of light given from the light guiding portion to the photoconductive layer meeting the following expression ofn.sub.1 sin .theta.
Abstract:
Acousto-optical modulators, such as a SAW modulators, with telescope arrays and superimposed volume gratings for light field generation are disclosed. These devices can employ pixelated demagnification and have layers of output optics, such as reflective gratings and/or arrays of transmissive refractive or diffractive lenses that manipulate the light emitted by the SAW modulator. In other cases, superimposed volume gratings are used, in which pixilation occurs in angle space.
Abstract:
According to embodiments of the present invention, an optical device is provided. The optical device includes a waveguide structure including a floating gate, and an optical waveguide arranged spaced apart from the floating gate, wherein the optical waveguide overlaps with the floating gate, a carrier injection portion arranged spaced apart from the floating gate, and an electrode arrangement, wherein, in response to a first voltage difference applied to the electrode arrangement, the optical device is configured to inject charge carriers from the carrier injection portion to the floating gate to cause a change in refractive index of the waveguide structure, and wherein, in response to a second voltage difference applied to the electrode arrangement, the optical device is configured to drive the charge carriers from the floating gate to the optical waveguide to deplete the charge carriers.
Abstract:
A controllable variable optical attenuator for attenuating an optical signal is described herein. The attenuator has an optical waveguide made from similar waveguide core and cladding materials and a coupling layer in close proximity to the waveguide which is configured to provide a difference between the refractive index of the coupling layer in proximity to the waveguide and the effective index of the waveguide. The index of the waveguide can be modified such that if the refractive index of the coupling layer is substantially lower than the effective index of the waveguide, minimal attenuation occurs to the light in the waveguide. Furthermore, if the refractive index of the coupling layer is substantially greater than the effective index of the waveguide, light is coupled into the coupling layer out of the waveguide to attenuate the optical signal. The amount of attenuation varies smoothly between these maximum and minimum values.
Abstract:
A tunable optical signal device and method of using the same having at least two filter elements, each of said filter elements being made of a material having an adjustable parameter, wherein the adjustable parameter is maintained at slightly different values for adjacent filter elements.
Abstract:
A modulator and a capacitor are integrated on a semiconductor substrate for modulating a laser beam. Integrating the capacitor on the substrate reduces parasitic inductance for high-speed optical communication.