Abstract: An optical record carrier (1) is provided with tracks having a groove (4) wobbled in a transverse direction and predetermined positions (18) along the track. The wobble comprises a substantially monotonous undulation (15). Local excursions (16) of the groove superposed on the undulation at the predetermined positions represent position information, such as addresses. The spatial frequency of the undulation is lower than that of the excursions.

Abstract: The present invention relates to a device (1) for scanning an optical recording medium (3), comprising an optical unit (5) for reading data from and/or writing data to said recording medium (3) by scanning said recording medium (3) with a radiation beam (21), said radiation beam (21) being positioned on said recording medium (3) in response to a tracking error signal, a tracking means (7) for generating said tracking error signal and a position control means (11) for controlling a radial scanning position of said radiation beam (21) in respect to a track on said recording medium (3).

Abstract: The invention relates to a record carrier having a data zone (7) and an initial zone (25) and comprising a main channel storing content and a side channel storing address information and data relevant for making recordings. It further relates to methods and devices for protecting content stored on a record carrier and for reading out protected content. To provide a record carrier with content protection information (20, 22, 24, 26, 28) stored on it, which can be used with legacy devices without causing confusion, which can substantially be produced without extra production steps and which can be easily read by common devices, it is proposed to store said content protection information (20, 22, 26, 28) for protection of said content in said side channel in said data zone (7).

Abstract: Optical recording method and apparatus using this method. An optical recording method and recording apparatus using this method is described in which an optimum write power of a radiation beam in the apparatus is set by writing a series of test patterns on an optical recordable medium, forming a read signal from the patterns, reading a preset value of the derivative of the modulation of the read signal with respect to the write power from the medium, and processing the read signal together with the preset value to derive an optimum value of the write power.

Abstract: In an optical record carrier recording method for forming marks and lands by irradiating a radiation beam onto a recording surface of an optical record carrier, the radiation beam for each mark to be recorded is set to at least one write power level (Pw) capable of forming a mark during a mark period (31) and, for each land between the marks, to at least one bottom power level (P0) incapable of forming a mark during a land period (32). When recording a wobble signal on the record carrier, in order to achieve a better wobble signal-to-noise ratio during writing, the bottom power level (P0) is temporarily raised to an intermediate power level (Pi) during an intermediate period (34). Preferably, the intermediate power level (Pi) is set within a range of from 1.5 to 6, in particular, from 2 to 4, times the bottom power level (P0).

Abstract: A device for recording and/or reading a record carrier has an optical head with a laser for generating a beam via a scanning spot on a track of the carrier. A detector detects a read signal and a sensor detects a sense signal from the beam. A control unit controls the laser power to a desired value. A correction unit generates a correction signal that depends on local optical properties of the record carrier derived from the sense signal measured on at least one part of the track near the scanning spot. The device corrects the power control using the correction signal. Furthermore, the record carrier can have prerecorded control parameters for setting the correction unit.

Abstract: A rewritable data storage medium has a rewritable recording layer provided with a tracking structure. The recording layer has a data recording area. An erasable identification mark is present in an identification mark area other than the data recording area. The data recording area has a first tracking structure, whereas the identification mark area is substantially free from a tracking structure or has a second tracking structure substantially different from the first tracking structure, such as including concentric or interrupted spiral grooves. Thus erasure of the identification mark is practically impossible, because the location of the erasing spot of a recorder cannot be controlled precisely in radial direction in the identification mark area.

Abstract: In methods and an optical recording apparatus using these methods, an optimum write power of a radiation beam in the apparatus is set by writing a series of test patterns on the optical recording medium, forming a read signal from the patterns and processing the read signal. Such processing involves fitting a function, preferably a straight line, to parameters obtained from the read signal without having to perform a differentiation step.

Abstract: The rewritable data storage medium (1) has a rewritable recording layer (9) provided with a tracking structure (8). Said layer (9) has a data recording area (5). An erasable identification mark is present in an identification mark area (4, 4?) other than the data recording area (5). The data recording area (5) has a first tracking structure (8?), whereas the identification mark area (4, 4?) is substantially free from a tracking structure or has a second tracking structure (8?) substantially different from the first tracking structure (8?). Thus erasure of the identification mark is practically impossible, because the location of the erasing spot of a recorder cannot be controlled precisely in radial direction.

Abstract: An optical record carrier (1) is provided with tracks having a groove (4) wobbled in a transverse direction and predetermined positions (18) along the track. The wobble comprises a substantially monotonous undulation (15). Local excursions (16) of the groove superposed on the undulation at the predetermined positions represent position information, such as addresses. The spatial frequency of the undulation is lower than that of the excursions.

Abstract: The invention relates to an optical record carrier recording method for forming marks and lands by irradiating a radiation beam onto a recording surface of an optical record carrier, the radiation beam for each mark to be recorded being set to at least one write power level (Pw) capable of forming a mark during a mark period (31) and for each land between the marks to at least one bottom power level (P0) incapable of forming a mark during a land period (32). The invention also relates to a recording device for carrying out such a method. When recording a wobble signal on the record carrier, in order to achieve a better wobble signal-to-noise ratio during writing, it is proposed according to the invention that the bottom power level (P0) is temporarily raised to an intermediate power level (Pi) during an intermediate period (34). Preferably, said intermediate power level (Pi) is set within a range of from 1.5 to 6, in particular from 2 to 4, times the bottom power level (P0).

Abstract: An optical record carrier (1) is provided with tracks having a groove (4) wobbled in a radial direction and predetermined positions (18) along the track. Embossed pits (18) at the predetermined positions represent addressing information. The phase of the wobble near the predetermined positions depends on whether a pit is present (18) on a predetermined position or not (19). The wobble changes phase between each two subsequent predetermined positions of which one on the positions contains no pit and the other position contains a pit.

Abstract: An optical record carrier (1) is provided with tracks having a groove (4) wobbled in a radial direction and predetermined positions (18) along the track. Embossed pits (18) at the predetermined positions represent addressing information. The phase of the wobble near the predetermined positions depends on whether a pit is present (18) on a predetermined position or not (19). The wobble changes phase between each two subsequent predetermined positions of which one on the positions contains no pit and the other position contains a pit.

Abstract: Methods and an optical recording apparatus using these methods are described in which an optimum write power of a radiation beam in the apparatus is set by writing a series of test patterns on the optical recording medium, forming a read signal from the patterns and processing the read signal. Such processing involves fitting a function, preferably a straight line, to parameters obtained from the read signal without having to perform a differentiation step. An optical recording medium for use by the methods and the apparatus is also described.

Abstract: A method and an optical recording apparatus for determining the optimum write power in an OPC-procedure are described. The method involves erasing a test area, recording test patterns in the test area, reading the recorded test patterns and determining the optimum write power from signal portions of the read signal. Erasing the test area, even when no signals are recorded therein, produces a reliable and unambiguous value of the optimum write power.

Abstract: The rewritable data storage medium (1) has a rewritable recording layer (9) provided with a tracking structure (8). Said layer (9) has a data recording area (5). An erasable identification mark is present in an identification mark area (4, 4′) other than the data recording area (5). The data recording area (5) has a first tracking structure (8′), whereas the identification mark area (4, 4′) is substantially free from a tracking structure or has a second tracking structure (8″) substantially different from the first tracking structure (8′).