| 摘要 |
PURPOSE:To prevent recorded information from being lost even if a memory element is exposed to solar light or room interior light. CONSTITUTION:A recording film 2 contg. a photochromic material and a reflection film 3 are successively formed on one surface of a substrate 1 consisting of a linear polarizer. A moving plate 5 consisting of a linear polarizer is provided on the other surface of this substrate 1. The polarization direction of the moving plate 5 can be set at the direction orthogonal with the polarization direction of the substrate 1 or the direction coincident therewith by moving this moving plate 5. The sunlight and the room interior light are prevented from being made incident on the recording film 2 from the moving plate 5 side if the polarization direction of the moving plate 5 is set in the direction orthogonal with the polarization direction of the substrate 1. Then, the loss of the information is prevented even if the optical memory element is exposed to the solar light or room interior light. The recording light and reproducing light are eventually made incident on the recording film 2 from the moving plate 5 side when the polarization direction of the moving plate 5 is set in the direction coincident with the polarization direction of the substrate 1. |
