| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an optical modulator which is provided with the conditions most suitable for transmission characteristics and on which an element which changes the optical phase by an electrooptic effect is mounted. <P>SOLUTION: The optical modulator is provided with an electrooptic effect element 2 which has a signal electrode 20 and earth electrodes 21 and 22 formed, which are provided with pads, respectively, and changes the optical phase by the electrooptic effect, a relay substrate 40 where coplanar lines connected to the pads of the signal electrode and the earth electrodes of the electrooptic effect element are formed on a dielectric substrate, and a connector 3 which is provided with a center conductor and an outer conductor connected to the coplanar lines of the relay substrate and supplies a modulation signal of a microwave area to the signal electrode of the electrooptic effect element, and the modulation signal includes the component of 30 GHz, and an height H (μm) of the pads is≤300, and an interval S (μm) between the pad of the signal electrode and the pads of the earth electrodes of the electrooptic effect element and the height H (μm) of the pads have relation -0.002H<SP>2</SP>+1.3H-160<S<0.0025 H<SP>2</SP>-1.6H+550. <P>COPYRIGHT: (C)2003,JPO</p> |
