Device for reading from and/or writing to optical recording media

• Main Author: BUECHLER, CHRISTIAN
• Format: Patent
• Language: English; French; German
• Published: 29.11.2006
• Subjects: INFORMATION STORAGE; INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORDCARRIER AND TRANSDUCER; PHYSICS

The present invention relates to a device for reading from and/or writing to optical recording media (4), which has a tracking unit (13), a four-quadrant detector (5), two summation points (15, 16) and a phase comparator (20) for tracking in accordance with the differential phase detection method, and also two variable delay elements (26A, 26B) which can be set by a control unit (24). The object of the present invention is to propose a device of this type which has the best possible compensation of the error in the track error signal (DPD-TE) and thus in the tracking signal, which error is caused on account of the lens movement. For this purpose, according to the invention an interference signal generating unit (22) is present whose output is connected to the tracking unit (13) and to a first input of the control unit (24), the second input of which is connected to the output of the phase comparator (20). The present invention is suitable for devices for reading from and/or writing to optical recording media, such as CD, CDI, CD-ROM, DVD, CDR, magneto-optical recording media and the like.