Some applications of ferroelectric ceramics

The linear, quadratic, and memory electro-optic effects characteristic of the lanthanum-modified lead zirconate titanate (PLZT) family of transparent ferroelectric ceramics materials are discussed. Some applications of a PLZT material (7% La; 65/35 Zr/Ti ratio) with sufficiently large grain size to exhibit the scattering effect are described. It was found that PLTZ elements used as variable optical attenuators can equalize the electrical outputs from the sensor elements in an optical sensor array. The angular distribution of the light scattered by a disk of PLZT was studied; wide-angled backscattering accounted for 20% of the incident light in the electrically depoled state, and for 12% in the poled state. The application of PLZT for electrically variable-contrast photographic printing and electronic deflection of light with 'memory,' and its use in electrically variable-focal-length mirror with 'memory' have also been demonstrated.