JP2515566B

PURPOSE:To obtain a memory medium which allows DRAW and rewriting by using a high-polymer liquid crystal compsn. as a recording layer and changing the optical thickness of a memory layer by the refractive index change of a recording part and non-recording part. CONSTITUTION:The recording and non-recording parts can be fixed respectively to the state of respectively different refractive indices by selecting two kinds from isotropic phase, nematic phase perpendicular orientation, nematic phase horizontal orientation, smectic phase perpendicular orientation, cholesteric phase focal conic, chiral smectic phase horizontal orientation, and chiral smectic phase perpendicular orientation and setting writing conditions such as direct heating or heating by laser irradiation and impressing of electric fields so as to meet the same. The thickness of the memory layer is previously controlled according to the difference in the refractive indices, by which the difference in the optical thickness between the recording part and non-recording part is set to the conditions adequate for reading. The compd. of [I] is exemplified as the ferroelectric high-polymer liquid crystal.