Anritsu Corporation

Nobuhiro Igarashi

Kenji Kawano

Masaya Nanami

Seiji Uchida

Yuji Sato

Toru Nakahira

Satoshi Matsumoto

Eiji Kawazura

Hiroaki Senda

Herein disclosed is an optical modulator, having: a substrate (); and a center and ground electrodes (to), in which the substrate has ridge portions (to), the center and ground electrodes are respectively formed above the ridge portions, the ridge portions below the center and ground electrodes respectively have top parts () having a respective first and second end points () separated with a distance of 'W', the substrate has a bottom surface () between the ridge portions having center and midway points () positioned with a respective distance of W/2 and W/N (3&#x2266;N&#x2266;25) from the first end point, the ridge portion below the center electrode has a normal line (), and the center point and the midway point define a straight line () crossed with the normal line at an angle larger or equal to 90.1&#xb0;.

Optical modulator

In an optical modulator comprising substratehaving electro-optical effect, two optical waveguidesformed in the substrate, buffer layerformed on the substrate, traveling-wave electrodehaving center conductorand ground conductorsabove the buffer layer, and ridge sections formed with recessed sectionstoby carving at least a part of the substrate where an electrical field strength of high-frequency electrical signal propagating the traveling-wave electrode is strong, in which the ridge sections include center conductor ridge sectionhaving the center conductor formed above and ground conductor ridge sectionhaving the ground conductor formed above, and the center conductor ridge section has one of the two optical waveguides formed therein, the recessed sections are practically symmetrical to the center line between the two optical waveguides and the traveling-wave electrode is practically symmetrical to the center line of the center conductor.

An optical modulator, including: a substrate; an optical waveguide embedded in the substrate; a traveling wave electrode mounted on the substrate and having a traveling wave applied thereon so that a light wave is modulated by the traveling wave with an electro-optic effect. The traveling wave electrode includes a center electrode and ground electrodes; in which the optical waveguide has a plurality of interaction optical waveguides that form a Mach-Zehnder optical waveguide that modulates the light wave in a phase modulation manner when the traveling wave is applied to the traveling wave electrode, the interaction optical waveguides form a region where respective widths of the interaction optical waveguides are different from each other, and the center electrode and the ground electrodes are positioned such that interaction efficiencies between the high frequency electric signal and the light wave guided in the respective interaction optical waveguides are substantially equal to each other.

Herein disclosed is an optical modulator, comprising: a substrate () having an electro-optic effect; an optical waveguide () formed in the substrate; a traveling wave electrode () including a center electrode () and ground electrodes () to have a high frequency electric signal applied thereto, the traveling wave electrode and the optical waveguide collectively forming a high frequency interaction portion () to have the incident light phase modulated under the condition that the high frequency electric signal is applied to the traveling wave electrode; and bias electrodes each including a center electrode () and ground electrodes () to have a bias voltage applied thereto, each of the bias electrodes and the optical waveguide collectively forming a bias voltage interaction portion () to have the incident light phase modulated under the condition that the bias voltage is applied to the bias electrode, in which the traveling wave electrode and the bias electrodes are extended in a propagation direction of the incident light with the traveling wave electrode () positioned between the bias electrodes ().

Growing community of inventors

Sagamihara, Japan

Nobuhiro Igarashi