Optical beam positioning at radial location of optical disc using series of segments at edge of optical disc

A non-transitory computer-readable data storage medium storing computer-executable instructions executable by a processing device to perform a method for précising positioning an optical beam of an optical disc device at a predetermined radial location on a non-data side of an optical disc, the method comprising:

• detecting, via the optical beam of the optical disc device, a frequency of a series of segments at an edge of the non-data side of the optical disc, the series of segments including a first series of segments and a second series of segments, the first series and the second series angularly interleaved on the non-data side, the first series non-overlapping the second series radially on the non-data side;
• determining whether the frequency is equal to a predetermined frequency corresponding to the optical beam detecting both the first series of segments and the second series of segments;
• in response to determining that the frequency is equal to the predetermined frequency, determining, via the optical beam of the optical disc device, a first amplitude corresponding to an extent of overlap of the optical beam on the first series of segments and a second amplitude corresponding to an extent of overlap of the optical beam on the second series of segments;
• determining whether the first amplitude is equal to the second amplitude;
• and
• in response to determining that the first amplitude is equal to the second amplitude, concluding that the optical beam is precisely located at the predetermined radial location.

An optical disc device comprising:

• a optical beam source to output an optical beam;
• a motor mechanism to rotate an optical disc inserted into the optical disc device and to move the optical beam source radially over a non-data side of the optical disc;
• and
• logic to precisely position the optical beam based on detection via the optical beam of a frequency of a series of segments at an edge of the non-data side of the optical disc, the series of segments including a first series of segments and a second series of segments, the first series and the second series angularly interleaved on the non-data side, the first series non-overlapping the second series radially on the non-data side.

An optical disc comprising:

• a substrate having a data side and a non-data side;
• and
• a series of segments at an edge of the non-data side of the optical disc at a predetermined frequency, the series of segments including a first series of segments and a second series of segments, the first series and the second series angularly interleaved on the non-data side, the first series non-overlapping the second series radially on the non-data side,
• wherein the series of segments is adapted to permit precise positioning of an optical beam of an optical disc device at a predetermined radial location on the non-data side of the optical disc.