High performance optical storage medium with separate mechanical servo tracks embedded within the medium

An optical storage medium comprising an optically transparent substrate carrying a thin film layer (13) of optically absorbing material with deformations (15) representing data formed in said thin film layer(13),

• said medium including
• a substrate (10), said substrate being coated with laminated films (19),
• said laminated films (19) including
• a conformal thin film (11) having a high optical index of refraction and having a thickness on the order of less than or equal to 30 nm,
• a dielectric film (12) and
• a thin film layer (13) of said absorbing material adapted for forming said deformations (15) between said thin film layer (13) of said absorbing material and said dielectric film (12),
• said medium including a servo track,
• said servo track comprising a plurality of mechanical undulations (14) of the surface of said substrate at the interface between said substrate (10) and said laminated films (19),and
• said mechanical undulations (14) being substantially absent from the surface (17) on which said deformations (15) are formed,
• whereby said servo data can be read through said substrate (10) without affecting the optical image of said deformations (15) on the upper surface of said thin film layer (13).

An optical storage medium including

• a substrate (10) carrying an optical storage trilayer configuration (19) having a high degree of optical efficiency, and including
• an optically absorbing active layer (13),
• with said optically absorbing active layer (13) of said optical storage medium being at a free surface, and
• said substrate (10) acting as a protective cover glass, and
• a series of layers (11,12,13) included in said trilayer configuration (19) including a high index of refraction material in one layer (11),less than or equal to about 30 nm thick, a dielectric layer (12) and an active layer (13),
• with said dielectric layer (12) interposed between said substrate (10) and said active layer (13).

An optical storage medium comprising

• an optically transparent substrate carrying a thin film structure comprising a data storage layer of material adapted to form deformations representing data formed in said thin film structure of data storage material,
• said medium including a servo track formed at an interface between said substrate and said structure,
• said servo track comprising internal mechanical undulations of the surface of said interface,
• said mechanical undulations being substantially absent from said surface of said thin film structure in which said deformations are formed,
• said substrate being coated with a first thin film (11) having a high optical index of refraction having a thickness on the order of less than or equal to 30 nm and said first thin film (11) being composed of a material consisting essentially of at least one element selected from the group consisting of silicon, Ti, Cr, Au, Pt and Pd for providing a partial optical mirror for said undulations of said servo track,
• said first film being coated with a polymeric film (12),
• said polymeric film being coated with said data storage layer,
• whereby said servo data can be read through said substrate without said servo data substantially affecting the optical image of said deformations on the upper surface of said thin film structure.