This series of laser phase modulators modulates the phase of the laser through the electro-optic effect and can be used for generating laser sideband signals and other purposes. Depending on the usage scenario, fiber coupled or free light propagation mode can be selected. Suitable for high-power laser modulation.
If the input polarization is parallel to the optical axis the optical phase can be modulated by applying different electric fields to the crystal. Applying an AC-Voltage results in a time-dependant phase and thus in a frequency shift in the output signal. Next to the carrier frequency fc sidebands appear D withf= fc ±n·fM (fM= frequency of the electric field, n∈N). The a plitude of the sidebands with respect to the carrier can be influenced by the amplitude of the applied voltage and are given by the Bessel functions. Many application, e.g. in quantum optics like Pound-Drever-Hall set-ups or laser frequency stabilization rely on such well-defined triplets of frequency.