| 摘要 |
PURPOSE:To increase an operating speed by specifying the electrode resistance and electrode width of the electrodes of a lumped constant type. CONSTITUTION:Waveguides 12, 14 provided on a substrate 10 having an electrooptical effect are provided with the electrodes 16, 18 of the concentrated constant type for executing the output control of guided light. The sectional area of the electrodes 16, 18 in the direction perpendicular to the propagation direction of the guided light are set at, for example, >=10mum<2> area in such a manner that the electric resistance attains <=2OMEGA/mm. The electrode width W is set at <=10mum and >=0.1mum. The acting of the electric resistance so as to lower the operating speed is substantially obviated if the value of the electric resistance is set at <=2OMEGA/mm. The inter-electrode capacity is decreased and, therefore, the operating speed is increased when the electrode width is specified to the above-mentioned value. |
