| 摘要 |
PURPOSE:To attain multi-value recording on a recording medium by controlling the irradiation energy density of a beam on a multi-value basis and recording the information while the light reflectance of a cholesteric high polymer liquid crystal layer is changed in multi values. CONSTITUTION:A vanadium oxide film is vapor-deposited as a light respirator 3 on a support substrate 1 and a cholesteric high polymer liquid crystal 5 is subjected to spin-coating on the film. Then a spacer 7 and a transparent protection plate 11 are used to form an air gap cell having an air gap layer 9. A circularly polarized plate 15 is provided on them. In using a light beam 13 not polarized, a circularly polarized plate whose spiral direction is coincident with that of the cholesteric high polymer liquid crystal is provided to an upper face or a lower face of the transparent protection plate 11 to improve S/N at the reproduction. The irradiated energy density of the beam 13 is controlled in multi values to change the light reflectance of the cholesteric high polymer liquid crystal in multi values and to record the information. |
