| 摘要 |
An optical record carrier comprises substantially parallel tracks being divided into recording units having an address area (23,24), adjacent address areas of adjacent tracks (43,44) comprising shared address marks (48). Shared address marks (47,48) are positioned in between adjacent tracks and arranged in sharing portions (40,41) of the address area, each sharing portion sharing address marks only to one side. The address area also comprises a free portion (39) which is free from shared address marks, which free portion is aligned with a sharing portion (42) of an adjacent address area. This is advantageous for reducing crosstalk in the address read signal. The sequence of the free and sharing portions within an address area differs so as to be matching in adjacent address areas. Further an apparatus for scanning the record carrier is described, which apparatus comprises an optical system (52) for generating a spot (66) on the record carrier via a radiation beam (65), tracking means (51), address recovery means (50,56) and positioning means (54) for moving the spot to a desired track. The address recovery means (50,56) are arranged for detecting the free portion and deriving the sequence of the free and sharing portions.
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