An optical endless phase shifting device includes a Mach-Zehnder structure operated in push-pull configuration and that creates a differential phase shift. The first stage outputs combined signals which are phase shifted by a phase shift of zero or π in the second stage by phase shifters provided in both arms of the second stage or in a first arm only. These additionally phase-shifted signals are combined to at least one output signal. A control device controls the phase shifters such that endless shifting capability is provided by switching one of the phase shifters or the single phase shifter of the second stage to the respective other value when the differential phase shift reaches a given range of the differential phase shift of [0;π/2] in the configuration with two phase shifters in the second stage or [0;π/2] in the configuration with only one phase shifters in the second stage.

A multi-section optical modulator and related method are disclosed wherein two waveguide arms traverse a plurality of successive modulating sections. A differential drive signal is applied separately to each waveguide arm of each modulating sections in synchronism with the transmission of light along the waveguide arms, effecting a dual differential driving of each section. By suitably selecting the number of modulating sections and the section length, a high modulation bandwidth and a high modulation efficiency may be achieved simultaneously for a given peak-to-peak voltage swing of the drive signal.

A problem is to provide a planar lightwave circuit optical device capable of facilitating mounting of connection to a printed circuit board and realizing downsizing of a device chip. A planar lightwave circuit optical device of the present invention is characterized by mounting an electrical connector (FPC connector) by means of soldering on an electrode pad of an electrical wire connected to an electrical drive unit (such as a heater) in a device formed by using a planar lightwave circuit (PLC).

An optical modulators is disclosed. The optical modulator includes a substrate, an optical waveguide formed on the substrate, a signal electrode formed on the optical waveguide via a first buffer layer and applying a modulation signal to the optical waveguide, and a bias electrode formed on the optical waveguide via a second buffer layer and applying a DC bias to the optical waveguide, the first buffer layer and the second buffer layer are formed in such a way that either one of the first buffer layer and the second buffer layer covers an end surface of the other one of the first buffer layer and the second buffer layer at a boundary part of the first buffer layer and the second buffer layer. Accordingly, an optical modulator with high reliability can be provided.

An electro-optical device includes an optical waveguide and an upper electrode provided on the optical waveguide, the optical waveguide is formed by turning back on a plane, the upper electrode has adjacent parts by turning back the optical waveguide, and an upper layer higher than the upper electrode between the adjacent parts includes a metal layer. Alternatively, an electro-optic device includes a plurality of Mach-Zehnder optical waveguides, wherein the Mach-Zehnder optical waveguide includes a first optical waveguide and a second optical waveguide, a first upper electrode is provided on the first optical waveguide and a second upper electrode is provided on the second optical waveguide, and an upper layer higher than the first upper electrode and the second upper electrode between the first upper electrode and the second upper electrode includes a metal layer. An electro-optic device is capable of suppressing electrical crosstalk between components and seeking wide frequency band.

The present disclosure relates to optical logic element technologies, and more particularly, to an optical logic element for photoelectric digital logic operation and a logic operation method thereof. Here, the element includes a driver member configured to drive a photoelectric integrated member, generate digital modulation information that is capable of being recognized by the photoelectric integrated member, and read an electrical signal outputted by the photoelectric integrated member; and the photoelectric integrated member configured to carry, by using a coherent optical signal, the digital modulation information inputted by the drive member, and perform, in a predetermined optical diffraction neural network, a digital logic operation on the coherent optical signal to obtain an operation result, generate, from the operation result based on a digital logic mapping relationship, the electrical signal, and output, after reading the electrical signal by using the drive member, the operation result.

Disclosed is a plasmonic device (10), comprising: a substrate (11); and a dielectric layer (13) arranged between a base metal layer (12) and a structured metal layer (14) which form with respect to the substrate (11) a vertical stack of layers, wherein the structured metal layer (14) includes arranged in a horizontal direction an input structure (141) for enabling an input section (21), a waveguide structure (142) for enabling a plasmonic waveguide (22), and an output structure (143) for enabling an output section (23), wherein the input section (21) is configured to receive an optical input signal (31) and transmit input power (41) to the plasmonic waveguide (22), wherein the plasmonic waveguide (22) is configured to receive input power (41) from the input section (21) and transmit output power (43) to the output section (23), and wherein the output section (23) is configured to receive output power (43) from the plasmonic waveguide (22) and transmit an optical output signal (33).

A semiconductor Mach-Zehnder optical modulator includes input-side lead-out lines, phase modulation electrode lines, and electrodes that apply modulation signals propagating through the phase modulation electrode lines to waveguides, respectively. The semiconductor Mach-Zehnder optical modulator further includes a conductive layer between a substrate and the waveguides, a plurality of first wiring layers connected to the conductive layer, and a second wiring layer that connects an electrode pad and the plurality of first wiring layers.

Provided is an IQ optical modulator including a nest-type MZ optical waveguide having optical modulation regions of I channel and Q channel End portions of an input optical waveguide and an output optical waveguide of the IQ optical modulator are located on a same edge face of a chip of the IQ optical modulator, an optical cross waveguide is included in which an optical waveguide between a first optical combiner and a second optical combiner of the nest-type MZ optical waveguide and the input optical waveguide cross each other, a first optical divider is provided between the I-channel optical modulation region and the Q-channel optical modulation region, and a light propagation direction in the first optical divider and a light propagation direction in the optical modulation regions are opposite to each other.

An optical transmitter comprises a directly coupled MZ interferometer and driver circuit. The MZ interferometer comprises a pair of differentially driven MZ electrodes configured to impart RF signals to light travelling through respective arms of the interferometer, and to receive DC bias as a positive voltage via lower n-type cladding of the MZ interferometer. The lower n-type cladding is at a different positive DC potential to an upper plane RF ground of the MZ interferometer, but the lower n-type cladding and the upper plane RF ground have similar AC potential. The MZ interferometer also comprises a pair of resistors in series configured to provide differential RF termination of the MZ electrodes; and a capacitive coupling between a virtual ground formed at a centre point between the pair of resistors and an RF ground configured to provide common-mode RF termination. The DC supply for the driver circuit is applied to the centre point of the RF termination.