Abstract: The optical storage medium comprises a substrate layer and a data layer disposed on the substrate layer, the data layer having a mark/space data structure being arranged in tracks, wherein on a first track, the marks are enlarged in length and the spaces are shortened in length, and on an adjacent track, the marks are shortened in length and the spaces are enlarged in length. The track pitch between adjacent tracks is particularly below a diffraction limit of ?/2*NA of a pickup for reading of the data.

Abstract: The optical storage medium comprises a substrate layer and a data layer disposed on the substrate layer, the data layer having a mark/space data structure being arranged in tracks, wherein on a first track, the marks are enlarged in length and the spaces are shortened in length, and on an adjacent track, the marks are shortened in length and the spaces are enlarged in length. The track pitch between adjacent tracks is particularly below a diffraction limit of ?/2*NA of a pickup for reading of the data.

Abstract: The present invention relates to a method for controlling the quality of storage media, and more specifically to a method for determining if the quality of a storage medium decreases. A method according to the invention has the steps of: determining one or more quality parameters of the storage medium; and comparing one or more of the determined quality parameters with previously determined quality parameters of the storage medium stored in a memory in case the quality of the storage medium has been determined before.

Abstract: The present invention relates to a method for coding a data stream, in which the digital sum value of the coded data stream should be close to zero and two alternative code words can be used for the coding at least for some of the possible data values. It is the object of the invention to propose a method for coding a data stream which provides for simple coding of the data stream whilst at the same time ensuring a digital sum value close to zero. According to the invention, the object is achieved by a method in which the digital sum value of the coded data stream is determined, this value is compared with a first or a second boundary value in dependence on the polarity of the coded data stream and a received data value is coded by a first or a second code word belonging to the respective boundary value in dependence on the result of the comparison.

Abstract: A method and an apparatus for creating a data block (Error Correction Code Block (ECC Block)) comprising a plurality of data sectors, which data block is provided with parity information, and a method and an apparatus for recovering data sectors from a data block provided with parity information.

Abstract: A stand alone CD player for reading data from a recording medium having data formatted in accordance with CD-like recording formats, for example, CD-ROM, CD-I and CD-V, stored thereon. According to the present invention, the playback of data from a recording medium having data in such a recording format is made possible by a virtual table of contents generated by the stand alone CD player. The virtual table of contents also enables sequential access to data stored on the recording medium that has a table of contents that cannot be read by the present CD player.