Abstract
The dielectric properties of ferroelectric liquid crystal were measured under external static electric field. The increase of dielectric permittivity by unwinding of helix of SC* under dc electric field and the depression of the permittivity by further increase of dc field were observed. The increase of permittivity was observed in more wide range of dc field in SA* phase than in SC* phase and then it was proved by polarizing microscopic observation that the molecular tilt was induced. The relaxation frequency in SA* had peak against dc field. These behaviors were considered in terms of electroclinic effect.