Polarization-Reflection Type Light Modulator Using Ferro Electrics

A polarization-reflection type of light modulator is proposed to utilize the deviation of reflectance of polarized light incident on an electro-optical medium at an angle greater than the Brewster angle. Feasibility of this method is theoretically investigated for the cases of real as well as complex refractive index. From numerical calculations it is shown that the intensity of light changes linearly with applied voltage under a certain condition, and that this method is applicable to such a ferroelectric materials as BaTiO3 SBN and other crystals. The modulation of He-Ne laser or Ar+ laser is demonstrated experimentally at radio frequencies using a BaTiO3 crystal. The merits of this type of light modulator are discussed and compared with crossed-polarizer tyoe of light modulator.