Abstract: A lamp provided with at least two LEDs of substantially the same colour and at least one driver for feeding each of said LEDs, wherein said at least one driver is adapted to feed said at least two LEDs during operation of the lamp at a different power level such that the largest difference in colour temperature of any pair of said LEDs during operation is less than the largest difference in colour temperature of any pair of said LEDs if being fed at an equal operational power level.

Abstract: The present invention relates to a method and a parameter-determining unit (100) for determining a first focus offset parameter value. The method of determining this parameter value for writing content data to a multilayer storage medium (114) comprises the steps of writing test data sequences using different estimated first focus offset parameter values (step 206), reading the test data sequences (step 206), determining values of at least one data deviation measure of the read test data sequences (step 206), and determining the first focus offset parameter value in dependence upon the determined values of at least one data deviation measure (steps 210,222), such that the block error rate of the read-out of content data, written to the multilayer storage medium (114) while using the determined first focus offset parameter value and read from the multilayer portable storage medium (114) while using the determined second focus offset parameter value, is minimized.

Abstract: The present invention relates to a record carrier, to a drive device for the record carrier, and to a method of providing at least one parameter that defines at least one characteristic of the record carrier on said record carrier. The at least one parameter is determined during a first access operation to the record carrier and is then written to a predetermined area of the record carrier by using a predetermined pattern of at least two different power levels. During a subsequent second access operation the at least one parameter is retrieved from the record carrier by detecting jitter values in the read-out signal. Thereby, a simple and reliable measure for storing and retrieving these parameters on the record carrier is provided.

Abstract: The present invention relates to determining an optimised write power used for writing electronic data on optical disc and includes a method, a device and a computer program product for determining a write power for writing electronic data on a medium (32,108), based on a sequence of written data, using a power control model including a written data deviation measure, a written data asymmetry and a written data asymmetry target value, comprising the steps determining the written data deviation measure for the sequence of written data (step 202), adjusting the written data asymmetry target value in relation to the written data asymmetry, if the written data deviation measure has changed (steps 218, 220, 226, 228), determining the write power in dependence of written data asymmetry (step 210), and writing another sequence of data on the medium using said determined write power (step 212), so as to obtain power optimised writing of data.

Abstract: An optimal power calibration process in which an OPC process is performed on the outer OPC area (12) of an optical disc (10) at a plurality of write speeds a, b and c, and an OPC process is also performed on the inner OPC area (14) at the write speed thereof. The optimal powers (and strategies) obtained by each OPC process for each speed is then used to create a function matching writing power level to speed. In order to create an accurate optimum laser power for all radii, two OPC power factors can be created: a media variation power factor a speed power factor In order to create the media variation power factor, Nx1 OPC information obtained from both the innermost and the outermost radii of the optical disc are used; whereas in order to create the speed power factor, the Nx1, Nx2, . . . , Nxm information obtained from the outermost radius of the disc is used. Using the above-mentioned two power factors, more accurate control of the required laser power for all radii can be achieved.

Abstract: A disc drive apparatus (1) is described, comprising a data engine system (20) and a data processing system (30) in data communication with each other. The data engine system (20) and the data processing system (30) are also in a conferring communication with each other regarding the timing of recalibration. The data engine system (20) is designed to determine (step 120; 320) a moment when a recalibration procedure would be desirable, and to send (step 121; 321) a recalibration request signal to the data processing system (30). The data processing system (30) may or may not send (step 230; 430) a recalibration permission signal to the data engine system (20). The data engine system (20) only performs (step 132; 332) a recalibration procedure after having received the recalibration permission signal from the data processing system (30).

Abstract: A fast optimum power control method is disclosed, with a laser power level being adjusted in a predetermined sequence at an ADIP/ATIP frame of an optical recording medium. Jitter is measured at each ADIP/ATIP frame in order to obtain an average jitter value for that particular frame, and hence power level.

Abstract: A disc drive apparatus (1) is described, for writing/reading information into/from a storage medium (2), such as an optical disc. After start-up, multiple recalibration processes are executed, wherein the recalibration processes are executed more frequently when writing/reading in a region (64) close to the outer disc radius than when writing/reading in a region (62) close to the inner disc radius.

Abstract: A disc drive apparatus (1) is described, for writing/reading information into/from a storage medium (2), such as an optical disc. After start-up, multiple recalibration processes are executed, wherein the recalibration processes are executed more frequently during an early phase of the write/read operation than during a later phase of the write/read operation.

Abstract: An apparatus for processing data which are placed on a data carrier (1) in various locations defined y locations codes and which are organized in accordance with data address codes for retrieving them, this apparatus comprising an explorer head (15) mounted in a sledge (16) for reading and/or writing data onto the carrier, a displacement measurer for measuring the position of said sledge, a displacement device (17) for placing said explorer head in a given position in accordance with a position code which is provided for executing an address jump. And a translator device for transforming data address codes into location codes having. The translator device has a correspondence table to establish a first correspondence between location codes and data address codes and updating means for establish a second correspondence more accurate than the first correspondence by taking account of previous jump.

Abstract: A disc recording device has a mode control unit (31) for switching the device either to a read mode or to a write mode. Reading and writing can be alternated for simultaneous recording and reproducing of video. A rotation speed control unit (37) sets the rotation speed of the record carrier, and has a speed selector (38) for selecting one of at least two speed settings for the read mode in dependence on an actual rotation speed of the record carrier during the write mode when switching from write mode to read mode. By setting the read speed to one of a limited number of settings the difference in rotation speed between said actual rotation speed and the speed in the read mode is limited. Due to the limited differences power dissipation is limited, while the performance of access time and playability of real-life discs is at a high level.