Sumitomo Osaka Cement Co., Ltd.

Hiroshi Murata

Junichiro Ichikawa

Satoshi Oikawa

Masayuki Motoya

Yasuyuki Ozeki

An optical modulator that includes a substratecomposed of a material having an electro-optical effect, an optical waveguideformed in the substrate, and a modulation electrodefor modulating lightwaves propagating through the optical waveguide, in which output light Lthat is output from the optical waveguide is guided with an optical fiber, wavelength dispersion characteristics of the optical fiber transmission line are compensated for by performing polarization reversalof the substrate along the optical waveguide with a predetermined pattern so that the substrate along the optical waveguide has waveform distortion with characteristics that are inverse to the wavelength dispersion characteristics of the optical fiber transmission line, and the compensation for the wavelength dispersion characteristics is adjusted to a predetermined level by disposing an adjustment member made of a dielectric material or a metal material in the vicinity of the modulation electrode.

Optical modulator

Provided is a light control element wherein stable operation at low driving voltage is possible. A light control element comprises a substrate () having an electro-optic effect, a plurality of optical waveguides () formed on said substrate (), and a control electrode () which is formed on said substrate and controls the phase of the light that propagates through the optical waveguides (), wherein the control electrode is provided with at least two resonance type electrodes () having the same resonant frequencies, and power supply electrodes () which supply a control signal to each resonance type electrode (); and the shape and forming position of each resonance type electrode (), and the supply position to each resonance type electrode () according to the power supply electrode () are set so as to allow odd mode coupling with respect to each other; and a control signal having the same phase or a prescribed phase difference is supplied to each resonance type electrode () by the power supply electrode ().

Light control element

An optical modulator includes: a substrate made of a material having an electro-optical effect; an optical waveguide formed on the substrate; and a modulation electrode for modulating an optical wave propagating through the optical waveguide, wherein emitted light emitted from the optical waveguide is guided by optical fiber, and polarization of the substrate is reversed in a predetermined pattern along the optical waveguide so as to provide waveform distortion having a characteristic opposite to a wavelength dispersion characteristic of the optical fiber.

An optical control element having a substratehaving an electro-optic effect, an optical waveguideformed on the substrate, and a control electrodethat is provided on the substrate and controls the phase of light that propagates through the optical waveguide, in which the control electrodehas a plurality of resonant-type electrodesandthat are disposed along the optical waveguideand have different resonance frequencies (fand f), an feeder electrodethrough which control signals are input and branched signal electrodes that are branched from the feeder electrode are connected to the respective resonant-type electrodes, and the branched signal electrode is configured to match a timing at which the electric control signal is applied to each of the resonant-type electrodes and a timing at which the light that propagates through the optical waveguide passes at the section of each of the resonant-type electrodes.

Growing community of inventors

Takarazuka, Japan

Hiroshi Murata