Abstract: A micro-opto-electro-mechanical systems (MOEMS) modulator based on the phenomenon of frustrated total internal reflection (FTIR). The modulator effects amplitude and phase modulation at the boundary of a waveguide. Wavelength-specific switching is achieved by spatially separating the wavelength channels by dispersing a broadband input signal into its wavelength components through a grating. In exemplary embodiments, an array of micro-fabricated actuators is used to switch or modulate wavelengths individually. Applications include wavelength and space-resolved phase and amplitude modulation of optical beams, and re-configurable add/drop switching of dense wavelength-division multiplexed (DWDM) optical communication signals.