PLZT attracts many researchers as a promising material for optical devices because of its useful characteristics: it changes its own refractive index depending on applied voltage by the Kerr effect. First, we examined the characteristics of simple PLZT. Then, we made a high-speed varifocal lens with PLZT which was significantly improved from what we reported before. We employ the novel lens-structure so that we can avoid undesirable deforming of the lens due to piezoelectric effects. We evaluated the characteristics of the lens quantitatively.