| 摘要 |
PURPOSE: To provide a liquid crystal element which can modulate light with enough contrast without using plural liquid crystal cells different in cell gap in the wavelength range of the light modulated by a polarized light-controlling type smectic liquid crystal element for optical modulation or even when the wavelength of light to be modulated is changed. CONSTITUTION: A phase difference plate is disposed in the optical path of a polarized light-controlling type smectic liquid crystal element for optical modulation in such a manner that the phase difference produced by the liquid crystal cell and the phase difference plate during modulating is controlled to satisfy the following relation. 0.8 × (wavelength λa/wavelength λb)<|(phase difference to transmitted light of wavelength λa)/(phase difference to transmitted light of wavelength λb)|<1.2 × (wavelength λa/wavelength λb). |
