An optical circuit includes one or more input waveguides, a plurality of output waveguides, and a reflector structure. At least a portion of the reflector structure forms an interface with the one or more input waveguides. The portion of the reflector structure has a smaller refractive index than the one or more input waveguides. An electrical circuit is electrically coupled to the optical circuit. The electrical circuit generates and sends different electrical signals to the reflector structure. In response to the reflector structure receiving the different electrical signals, a carrier concentration level at or near the interface or a temperature at or near the interface changes, such that incident radiation received from the one or more input waveguides is tunably reflected by the reflector structure into a targeted output waveguide of the plurality of output waveguides.

An optical waveguide device includes a substrate on which an optical waveguide is formed, and an object that is disposed on the substrate. The optical waveguide includes a mode conversion/branching portion that converts a mode of a light wave propagating through the optical waveguide and branches the light wave, and the object is disposed to cover a part or the whole of the mode conversion/branching portion or not to cover the mode conversion/branching portion when the substrate is viewed in a plan view. In a case where the object is disposed to cover a part of the mode conversion/branching portion, the object is disposed not to consecutively cover a section over a length of a predetermined value or higher in an advancing direction of a light wave.

An optical circuit includes one or more input waveguides, a plurality of output waveguides, and a reflector structure. At least a portion of the reflector structure forms an interface with the one or more input waveguides. The portion of the reflector structure has a smaller refractive index than the one or more input waveguides. An electrical circuit is electrically coupled to the optical circuit. The electrical circuit generates and sends different electrical signals to the reflector structure. In response to the reflector structure receiving the different electrical signals, a carrier concentration level at or near the interface or a temperature at or near the interface changes, such that incident radiation received from the one or more input waveguides is tunably reflected by the reflector structure into a targeted output waveguide of the plurality of output waveguides.

An optical device includes a first substrate, a second substrate, a plurality of separation walls, one or more optical waveguides, and one or more spacers. The first substrate has a surface which extends in a first direction and a second direction intersecting the first direction. The second substrate faces the first substrate. The plurality of separation walls are positioned between the first substrate and the second substrate and extend in the first direction. The one or more optical waveguides are positioned between the first substrate and the second substrate and include one or more dielectric members which are positioned between the plurality of separation walls and which extend in the first direction. The one or more spacers are directly or indirectly sandwiched between the first substrate and the second substrate and positioned around the one or more optical waveguides.

In various embodiments, an apparatus comprises a composite backplane that modulates light from a light source, where the composite backplane comprises an electronics layer disposed on a substrate, a photonics integrated circuit (IC) layer disposed on the electronics layer that causes light from the light source to propagate in a first direction, and an active light modulation (ALM) interface layer disposed on the photonics IC layer controls an ALM interface layer in order to control the light propagating in the first direction.

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.

A Y-branch dual electro-optical phase modulator (YBDPM) has a stitched-in zinc oxide diffused waveguide. It is more vacuum stable and has higher resistance to photorefractive damage than currently used Ti-diffused waveguides. The YBDPM is useful in Fiber Optic Gyroscopes (FOG), especially in low frequencies applications.

An integrated optical beam steering device includes a planar dielectric lens that collimates beams from different inputs in different directions within the lens plane. It also includes an output coupler, such as a grating or photonic crystal, that guides the collimated beams in different directions out of the lens plane. A switch matrix controls which input port is illuminated and hence the in-plane propagation direction of the collimated beam. And a tunable light source changes the wavelength to control the angle at which the collimated beam leaves the plane of the substrate. The device is very efficient, in part because the input port (and thus in-plane propagation direction) can be changed by actuating only log.sub.2 N of the N switches in the switch matrix. It can also be much simpler, smaller, and cheaper because it needs fewer control lines than a conventional optical phased array with the same resolution.

The present invention discloses an high-contrast photonic crystal “OR”, “NOT” and “XOR” logic gate, comprising a six-port two-dimensional photonic crystal, a nonlinear cavity unit and a cross-waveguide logic gate unit; the high-contrast photonic crystal “OR” logic gate includes a first reference-light input port, two first idle ports, two first signal-input ports and a first signal-output port; the high-contrast photonic crystal “NOT” logic gate includes two second reference-light input ports, two second idle ports, a second signal-input port and a second signal-output port; and the high-contrast photonic crystal “XOR” logic gate includes a three reference-light input port, two three-idle ports, two three-signal input ports and a three-signal output port; the cross-waveguide logic gate unit is arranged with different input or output ports; and the nonlinear cavity unit is coupled with the cross-waveguide logic gate unit. The structure of the present invention is easy to integrate with other optical logic elements.

Provided is a variable wavelength laser device that achieves phase control of high precision while restraining thermal interference and stably outputs emission light of desired wavelength.

The variable wavelength laser device of the present invention includes: an optical amplification means including a low-reflective surface that reflects light of wavelengths other than a predetermined wavelength and emits light of the predetermined wavelength; a wavelength control means for controlling wavelength of light being transmitted through the optical waveguide; a phase control means for controlling phase of light being transmitted through the optical waveguide using heat emitted by a heating means; a reflection means for totally reflecting the inputted light; and a heat dissipation means for restraining transfer of heat emitted by the heating means to regions other than a region in which the phase control means is disposed.