| 摘要 |
A read/write head for an optical storage system is implemented using at least one liquid crystal cell, the liquid crystal cell being of the type in which the retardance of a radiation beam therethrough is determined by an externally applied voltage. In an optical storage system of the type having regions of differing absorption to determine logic states the liquid crystal cell can activated by a voltage which provides the liquid crystal cell with the characteristics of a quarter wave plate. In this configuration, the liquid crystal cell is positioned in the collimated beam between the linearizing beam splitter and the storage medium. In the optical storage system in which logic states are identified with the orientation of magnetic regions, the liquid crystal cell is positioned between the linearizing beam splitter and the beam splitter used to separate the radiation components. When two liquid crystal cells with controllable retardance are included in read/write head, a read/write head which can be used in either type of optical storage system can be provided. The use of the adjustable retardance liquid crystal cells permits both an optimization of the read/write head, but permits adjustment to compensate for changes in the optical properties.
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