Zen Research (Ireland), Ltd.

Dragsholm Wireless Holdings LLC

Koby Finkelstein

Steven Robert Rogers

Tatiana Tania Kosoburd

Toshihiro Sasaki

Joseph Kedmi

Zvika Daube

Methods and apparatus are provided for reducing cross-talk and jitter caused by track offsets in multi-beam optical disks. The method and apparatus involve using split detectors and cross-talk cancellation algorithms in the multi-element photodetector of the multi-beam optical disks. The cross-talk cancellation algorithms are applied according to the value of the track offset as a function of the track pitch.

Methods and apparatus for cross-talk and jitter reduction in multi-beam optical disks

Digital read channel for optical disk reader

In a CD-ROM reader system wherein five adjacent tracks of a CD-ROM are separately illuminated by five light beams of an optical pickup, a recorded data readout system simultaneously reads the recorded data of the separate tracks by detecting the received light outputs of the returned beams, and outputs the data in the sequence in which it was recorded. For example, if one light beam becomes unreadable by the recorded data readout system, the system will read the recorded data using the remaining four light beams. This readout is performed in recurring operations in which data is read for approximately one revolution of the CD-ROM; then, after there are no longer any gaps in the combined data, the pickup is track-jumped forward by approximately two tracks. At this point the recorded data is again read for one revolution, and the process repeats.

Multibeam optical disk readout method and apparatus

Growing community of inventors

Kafar Saba, Israel

Koby Finkelstein