Linearization schemes for Pockels cell light intensity modulators

We present two optoelectronic schemes that enhance the linearity of light intensity modulators based on the Pockels effect. The first scheme consists in a Sagnac interferometer which has an electro-optic modulator in the loop of the interferometer. The linearity is improved by feedback which uses part of the output light intensity to generate an electrical signal that is directed to the Pockels cell. The second scheme consists of two Pockels cells placed between two polarizers. The linearity is improved by properly choosing the orientation of the crystal axes as well as the two DC bias-voltages applied to the cells. The theoretical and experimental analysis of the proposed schemes are presented.