Abstract:
There is provided volume holographic data recording media having a recording layer which is capable of recording interference fringes generated by interference of light having excellent coherence as fringes having different refractive indexes and undergoes holographic data recording by an amount of spatial shift distance of not more than 3 m which is smaller than that of conventional media.
Abstract:
A stable electrochromic stack is provided that is able to persistently hold a desired optical state (1). The stable electrochromic stack has at least two states. One state may be, for example, a bleached state in which light may readily pass, and the other state may be a colored state that distorts or interferes with the passage of light. Advantageously, the persistent electrochromic stack holds one or both of the optical states without the application of external power. The persistent time period may extend for days, weeks, or years depending on particular constructions, and on application requirements.
Abstract:
The present invention relates to an optical storage medium (20) comprising a first data area (21) for storing content and a second data area (23) for storing limitation data (24) for limiting access to at least a portion of the first data area. It is desired that the period of time for which access to content stored on the storage medium is limited, such that, for instance, after said period of time unlimited access to said content is granted. To achieve this a state change means (27) is provided on the storage medium, adapted for changing its optical reflectivity and/or transmittance over time, said change directly preventing access to the second data area after a limited period of time or being indirectly used to decide whether access to the at least one portion of the first data area shall be limited according to said limitation data.
Abstract:
The invention relates generally to optical storage devices, such as DVDs and CDs, on which compositions containing dyes are disposed so as to facilitate limited or selective use of at least a portion of the content of the optical storage devices. The invention also relates to methods of making limited-use content optical storage devices.