Electrowetting may be used in an optical device such as a shutter or an attenuator by configuring the device to utilize: (a) mode leakage or spoiling; (b) scattering or absorption; (c) metallic, dielectric, total internal, or frustrated total internal reflection so as to direct the optical signal to a port where the signal is discarded; (d) delta-beta (evanescent) or damped resonant coupling so as