Fig. 1: Electro-optic effect and some application.

a Three contributions of Electro-optic (EO) coefficients: acoustic phonons, optic phonons, and electronic. b–f EO effect devices: b high-speed EO phase modulator, where an electric field changes the phase delay of a laser beam sent through the crystal; c EO Q-switch are modulators where the transmission is either switched on or off, rather than varied gradually. d Electrically tunable lenses, comparing to the traditional solid lenses with fixed refractive index, the refractive index of lenses is electrically tunable. Therefore, the focal length of lens is tunable by properly controlled the optical phase as aspheric or Fresnel lens phase profile. e EO laser beam scanner refract light by applying a phase delay by changing the refractive index of the medium, and by adjusting the voltage applied to the crystal to change the steering angle to EO control the phase delay across the beam cross-section. f Polarization modulator can thus be seen as a voltage-controlled waveplate, and it can be used for modulating the polarization state