Patent ID: 6498775
Filing Date: 2002-12-24
Classification: G11B,Y10S,Y10T

Abstract:
An information storage device comprising:a plurality of information storage structures, each said i-th information storage structure being indexable as an i-th information storage structure where i=1, 2, 3, . . . N and each said i-th information storage structure having an undulated surface with first and second surface heights and a plurality of first and second information value storage locations recorded in each said i-th information storage structure and corresponding to said first and second surface heights, respectively; and wherein each said first and second information value storage location recorded in said undulated surface of said i-th information structure (i) is characterized by a characteristic wavelength band &Dgr;&lgr;i defined about a prespecified wavelength &lgr;i, (ii) reflects spectral components that are incident to said first or second information value storage location, and have a wavelength within said characteristic wavelength band &Dgr;&lgr;i, and (iii) transmits spectral components that are incident to said first or second information value storage location and have a wavelength outside of said characteristic wavelength band &Dgr;&lgr;i, so that an optical pick-up, arranged for detecting spectral components incident to said i-th information storage structure, is capable of detecting at a first signal level, spectral components reflected from each said first information value storage location in said i-th information storage structure, and detecting at a second signal level different than said first signal level, spectral components reflected from each said second information value storage location in said i-th information storage structure.