US 2003/0206503 A1 · MULTI-ELEMENT DETECTOR AND MULTI-CHANNEL SIGNAL CONDITIONER FOR USE READING MULTIPLE TRACKS OF OPTICAL DISKS HAVING DIVERSE FORMATS

Abstract

Apparatus and methods are provided for using a single multi-element detector and multi-channel signal conditioning circuitry to simultaneously read multiple tracks from either a CD disk or a DVD disk. The multi-element detector has a staggered arrangement and includes elongated detector elements, so that multiple reading beams reflected from multiple tracks of a CD disk are projected onto the detector, as are multiple reading beams reflected from multiple tracks of a DVD disk. The multi-channel signal conditioning circuitry conditions the signals produced by the multi-element detector, and produces signals for each of the tracks that is simultaneously read, as well as a tracking error signal, a focus error signal, a magnification error signal, and signals useful for reading DVD-RAM disks and for rapidly accessing tracks on an optical disk.

Claims35

Dependent claims

Multi-channel signal conditioning circuitry for use in an optical drive that simultaneously reads multiple tracks from either one of first and second types of optical disks, the first and second types of optical disks having different track pitches and data densities, the multi-channel signal conditioning circuitry comprising:

a switch that selectively switches between a first set of inputs signals from multiple tracks of the first type of optical disk and a second set of inputs signals from multiple tracks of the second type of optical disk, the switch producing a set of data signals;
focus error detection circuitry that produces a focus error signal from a first subset of data signals selected from the set of data signals;
tracking error detection circuitry that produces a tracking error signal from a second subset of data signals selected from the set of data signals;
magnification error detection circuitry that produces a magnification error signal from a third subset of data signals selected from the set of data signals;
and
a plurality of filter circuits, each one of the filter circuits using one or more of the data signals from the set of data signals to produce a filtered output signal representing the data of one of the multiple tracks of either the first type or the second type of optical disk.

3 more elements

A method of simultaneously reading a plurality of data tracks from either one of first and second optical disks having different formats, the method comprising:

providing a central detector element and a plurality of non-central detector elements, the central detector element and the plurality of non-central detector elements producing a plurality of data signals;
generating a plurality of reading beams including a plurality of non-central reading beams;
focusing the plurality of non-central reading beams onto a surface of one of the first or second optical disks to generate a plurality of non-central reflected beams, each one of the plurality of non-central reading beams being focused onto a corresponding one of plurality of data tracks to generate a corresponding one of the plurality of non-central reflected beams;
if the first optical disk is read, projecting each one of the plurality of non-central reflected beams onto a first region of each one of the plurality of non-central detector elements, and if the second optical disk is read, projecting each one of the plurality of reflected beams onto a second region of each one of the plurality of non-central detector elements, the first region of each one of the plurality of non-central detector elements is spaced apart from the second region of that non-central detector element;
and
sending the plurality of data signals to multi-channel conditioning circuitry that filters the plurality of data signals to produce a plurality of output signals, detects a focus error, and detects a tracking error.

3 more elements

Dependencies are inferred from the claim text.

Multi-element detector and multi-channel signal conditioner for use reading multiple tracks of optical disks having diverse formats

Life of this patent

Multi-element detector and multi-channel signal conditioner for use reading multiple tracks of optical disks having diverse formats

Life of this patent

Abstract

Claims35