To provide a coplanar type waveguide interference type electrooptical modulator which has reduced bias point sensitivity of the module to an ambient temperature and an impressing RF.
First and second waveguides formed on an electrooptical substrate are incorporated in the modulator. The RF electrode is arranged on the electrooptical substrate between the first and second waveguide. An earth electrode which may include a slot is arranged closely to the second waveguide. A protective earth electrode absorbs heat from the RF electrode and is arranged closely to the first waveguide in order to balance a thermal stress in two waveguides. Insulating material may be also arranged closely to the first wavegude in order to balance the thermal stress in two waveguides.
GRYK THOMAS JOSEPH
KISSA KARL M
WOOTEN ED
FUERST RUSSELL
| JPH11237593A | 1999-08-31 | |||
| JPH07234391A | 1995-09-05 |