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AssigneeKoninklijke Philips Electronics N.V.
InventorsCornelis Marinus Schep, Aalbert Stek, Sebastian Egner, Constant Paul Marie Jozef Baggen
Estimating the term…
A record carrier (1) is described which has a servo track (4) indicating an information track (9) intended for recording information blocks, which servo track (4) has a variation of a physical parameter, a so called wobble. The wobble is modulated for encoding record carrier information, such as addresses. The servo track is subdivided in modulated parts in which the frequency and/or phase of the variation deviates from the wobble frequency, and non-modulated parts. The slope of the wobble is substantially continuous at transitions between the modulated and non-modulated parts by using wobbles (25,26,27,28) starting at the maxima or minima of the wobble in the first part of the modulated parts.
Record carrier comprising a servo track (4) indicating an information track (9) intended for recording information blocks, which servo track (4) has a variation of a physical parameter at a predetermined frequency which variation is modulated for encoding record carrier information, and which servo track has modulated parts in which the frequency and/or phase of the variation deviates from the predetermined frequency, and non-modulated parts having only said periodic variation, characterized in that the slope of the variation is substantially continuous at transitions between the modulated and non-modulated parts.
Recording and/or playback device comprising means for writing and/or reading information blocks in an information track (9) on a record carrier that comprises a servo track (4) indicating the information track (9), which device comprises means for scanning the servo track (4) and demodulation means for retrieving record carrier information from a signal generated by a variation of a physical parameter of the servo track at a predetermined frequency, which servo track has modulated parts in which the frequency and/or phase of the variation deviates from the predetermined frequency, and non-modulated parts having only said periodic variation, characterized in that the demodulation means comprise detection means (50) for detecting the modulated parts starting at transitions between the modulated and non-modulated parts at which the slope of the variation is substantially continuous.
Method of manufacturing a record carrier, in which the record carrier is provided with a servo track (4) indicating an information track (9) intended for recording information blocks, which servo track (4) is provided with a variation of a physical parameter at a predetermined frequency which variation is modulated for encoding record carrier information, and which servo track is provided with modulated parts in which the frequency and/or phase of the variation deviates from the predetermined frequency, and non-modulated parts having only said periodic variation, characterized in that transitions between the modulated and non-modulated parts are provided keeping the slope of the variation substantially continuous.
Dependencies are inferred from the claim text.