| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a progressive wave type optical modulation element that can suppress electric crosstalk and suppress increase in manufacturing cost even when a substrate has two signal electrode input parts on the same face side. <P>SOLUTION: A progressive wave type optical modulation element includes a substrate 1 having an electro-optical effect, an optical waveguide 2 including a Mach-Zehnder optical waveguide formed on the substrate, and a modulation electrode for modulating the optical wave progressing along the optical waveguide. The modulation electrode includes a first signal electrode 31 and a second signal electrode 32 for applying different modulation signals to two branch waveguides 21 and 22 of the Mach-Zehnder optical waveguide. Each signal electrode includes modulation signal input parts T1 and T2 on the same face side of the substrate. In at least a part of the signal electrode ranging from the modulation signal input parts T1 and T2 to an operation part S, a ground electrode disposed between the first signal electrode 31 and the second signal electrode 32 is separated into a first ground electrode 41 along the first signal electrode and a second ground electrode 42 along the second signal electrode. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
