The first transmission line has a width perpendicular to a transmission direction. The first electrode has a width not exceeding the width. The first electrode is opposed to the first transmission line. The ground layer has a positional relationship with each portion of the first transmission line. The ground layer is next to the first transmission line on at least one side consisting of a first side along a thickness direction of the mounting substrate, and a second side and a third side with the first transmission line interposed therebetween. The first transmission line is bonded to the first electrode and has the width equivalently, at least, at a portion of the first transmission line. The portion equivalently has the positional relationship with the ground layer. The portion is next to the ground layer in an equivalent shape along the transmission direction.

An optical phased array including a wafer, optical waveguides, a root optical waveguide, the root optical waveguide being optically connected at one end to one optical waveguide, another end of the root optical waveguide constituting an optical port, optical couplers disposed in an array and located on the wafer, the optical waveguides optically connecting the optical couplers to the optical port via respective optical paths, one optical path per optical coupler, configurable optical delay lines; each configurable optical delay line being disposed in one respective optical path from the respective optical paths; the configurable optical delay lines being configured such that the optical couplers emit a non-planar phase front near field radiation pattern from light received from a light source coupled to the optical port.

An optical module according to one embodiment includes: a package having a first surface and a second surface; a driver IC mounted on the first surface via a heat sink block; an optical circuit element mounted on the second surface via a temperature adjustment element; and a flexible substrate mounted on the driver IC and the optical circuit element, and electrically connected to the driver IC and the optical circuit element. The flexible substrate includes a main body extending in a first direction and a second direction intersecting the first direction, and a wiring formed on the main body. The main body includes a first end facing an optical circuit element. The wiring includes a first lead portion protruding from the first end to an outside of the main body along the first direction. The first lead portion is connected to the optical circuit element.

Disclosed are an optical modulation device and a phase modulation method using the same. The optical modulation device includes a reflection plate, an insulating film over the reflection plate, dielectric patterns aligned on the insulating film in a first direction and extended in parallel in a second direction intersecting the first direction, and first and second graphene patterns provided between the dielectric patterns aligned in the first direction and arranged in an alternating fashion. The first and second graphene patterns are in direct contact with the insulating film and the dielectric patterns are in direct contact with the insulating film at locations between the first and second graphene patterns. A width of each of the first graphene patterns in the first direction is different from a width of each of the second graphene patterns in the first direction.

A method and apparatus for protecting an optical sensor is disclosed. A fixed filter having a fixed passband for light transmission is placed in front of the optical sensor. A programmable filter having a variable passband for light transmission is placed in front of the fixed filter. A controllable voltage source controls a voltage at the programmable filter that shifts the passband of the programmable filter from a first state in which the passband of the programmable filter is substantially the same as the passband of the fixed filter and a second state in which the passband of the programmable filter is different than the passband of the fixed filter.

An optical full-field transmitter for an optical communications network includes a primary laser source configured to provide a narrow spectral linewidth for a primary laser signal, and a first intensity modulator in communication with a first amplitude data source. The first intensity modulator is configured to output a first amplitude-modulated optical signal from the laser signal. The transmitter further includes a first phase modulator in communication with a first phase data source and the first amplitude-modulated optical signal. The first phase modulator is configured to output a first two-stage full-field optical signal. The primary laser source has a structure based on a III-V compound semiconductor.

Embodiments described herein may be related to apparatuses, processes, and techniques directed to phase match and impedance match to enable a higher baud rate for ultra-high-speed TW-MZM for 100 Gbaud or above for PAM applications, and/or 120 Gbaud or above for QAM applications. Embodiments described herein may include ultra-high-speed TW-MZM based on differential signal-to-signal (SS) TW using a push-pull PN structure. These embodiments facilitate high speeds for a TW-MZM due to decreased complexity by eliminating a ground in the TW. Other embodiments may be described and/or claimed.

A tunable metamaterial has a two dimensional array of resonant annular ring elements; and a plurality of voltage controllable electrical tuning elements disposed in or adjacent openings in each of said ring elements, each of said voltage controllable electrical tuning element ohmically contacting portions of only one of said ring elements. The voltage controllable electrical tuning elements may comprise highly doped semiconductor tunnel diodes, or the charge accumulation layer at the semiconductor/insulator interface of a metal-insulator-semiconductor structure, or nanoelectromechanical (NEMs) capacitors. The tunable metamaterial may be used, for example, in an optical beam steering device using the aforementioned tunable optical metamaterial in which a free-space optical beam is coupled into a receiving portion of a plane of the optical metamaterial and is steered out of a transmitter portion of the plane of the optical metamaterial in controllable azimuthal and elevational directions. The tunable metamaterial additionally has other applications.

An optical modulator uses an optoelectronic phase comparator configured to provide, in the form of an electrical signal, a measure of a phase difference between two optical waves. The phase comparator includes an optical directional coupler having two coupled channels respectively defining two optical inputs for receiving the two optical waves to be compared. Two photodiodes are configured to respectively receive the optical output powers of the two channels of the directional coupler. An electrical circuit is configured to supply, as a measure of the optical phase shift, an electrical signal proportional to the difference between the electrical signals produced by the two photodiodes.

An optical phased array includes, in part, a multitude of optical signal emitters and a multitude of optical signal phase/delay elements each associated with and disposed between a different pair of the optical signal emitters. Each optical signal phase/delay element is adapted to cause a phase/delay shift between the optical signals emitted from its associated pair of optical signal emitters. Each optical signal phase/delay element is optically a ring resonator that includes a p-i-n junction. By varying the bias applied to the p-i-n junction, the phase/delay generated by the ring resonator is varied. Furthermore, each optical signal emitter is optionally an optical grating having a multitude of grooves. The groove lengths of the optical gratings are optionally selected so as to increase along the direction of travel of the input optical signal through the optical phase array.