For Q-switching, coupling and intensity modulation
Inrad Optics Pockels cells can quickly switch the polarization direction of light beams. Their uses include:
Q-switching of laser cavities.
Coupling light in and out of regenerative amplifiers.
Light intensity modulation when used in conjunction with a pair of polarizers.
Selection of the best crystalline material to use as the Pockels cell medium is determined by the wavelength of operation and performance requirements—such as damage threshold, average power handling ability, contrast ratio, extinction ratio and repetition rate.
KD*P is routinely used for Q-switching applications from the UV to about 1.1 μm. KD*P Pockels cells features large apertures with low voltages. The surfaces of the crystal are coated with an AR sol-gel or dielectric coating.
BBO can be useful at wavelengths from the UV to about 2 μm. The crystal can handle high average powers better than KD*P, although it has a relatively small electro-optic coefficient. So BBO Pockels cells typically require higher voltages.