Optical disc apparatus and control method thereof

Patent metadata

Field	Value
Publication number	US-9564167-B2
Application number	US-201615078285-A
Country	US
Kind code	B2
Filing date	Mar 23, 2016
Priority date	Mar 26, 2015
Publication date	Feb 7, 2017
Grant date	Feb 7, 2017

Abstract

An optical disc apparatus is disclosed. The optical disc apparatus includes: a driver configured to rotate an optical disc having a recording surface for data; an optical pick-up configured to emit a light beam to the optical disc rotated by the driver; and at least one processor configured to operate the optical pick-up to focus the light beam emitted from the pick-up unit to perform one of recording and reproducing the data on the recording surface and track curvature of the recording surface within a preset allowable range, and to process the light beam reflected from the recording surface, the at least one the processor further configured to increase the allowable range if it is determined that the focus of the light beam cannot track the curvature of the recording surface in a section of the recording surface.

First claim

What is claimed is:

1. An optical disc apparatus comprising:
a driver configured to rotate an optical disc having a recording surface for data;
an optical pick-up configured to emit a light beam to the optical disc rotated by the driver; and
at least one processor configured to operate the pick-up to focus the light beam emitted from the optical pick-up to perform one of recording and reproducing the data on the recording surface and track curvature of the recording surface within a preset allowable range, and to process the light beam reflected from the recording surface,
the at least one the processor further configured to increase the allowable range if it is determined that the focus of the light beam cannot track the curvature of the recording surface in a section of the recording surface.

2. The optical disc apparatus according to claim 1 , wherein the at least one processor is configured to control the optical pick-up to be adjusted in position with respect to an optical axis of the light beam in response to a focus error signal that indicates an extent of deviation of the light beam from focus on the recording surface, and to determine that the focus of the light beam cannot track the curvature of the recording surface in the section if the focus error signal has an amplitude equal to or greater than a preset value.

3. The optical disc apparatus according to claim 2 , wherein the optical pick-up is configured to derive a reproducing signal including a data recording pattern formed along a track of the recording surface based on the light beam reflected from the recording surface, and
the at least one the processor is configured to determine that the focus of the light beam cannot track the curvature of the recording surface in the section if the focus error signal has an amplitude equal to or greater than the preset value and the reproducing signal of the data recording pattern based on the reflected light beam.

4. The optical disc apparatus according to claim 1 , wherein the at least one processor is configured to increase the allowable range by increasing an operation speed of the optical pick-up with respect to a rotation speed of the optical disc.

5. The optical disc apparatus according to claim 4 , wherein the driver includes a shaft configured to support the optical disc and a spindle motor for driving the shaft, and
the at least one processor is configured to increase the operation speed of the optical pick-up with respect to the rotation speed of the optical disc by decreasing revolutions per unit time of the spindle motor.

6. The optical disc apparatus according to claim 4 , wherein the at least one processor is configured to increase the operation speed of the optical pick-up with respect to the rotation speed of the optical disc by increasing a focus moving speed of the light beam.

7. The optical disc apparatus according to claim 6 , wherein the optical pick-up comprises an actuator configured to adjust a focus height of the light beam by adjusting a position of the optical pick-up along an optical axis of the light beam, and
the at least one processor is configured to increase the focus moving speed of the light beam by increasing operation sensitivity of the actuator.

8. The optical disc apparatus according to claim 7 , wherein the actuator is configured to increase a speed of moving the optical pick-up as the operation sensitivity increases.

9. The optical disc apparatus according to claim 7 , wherein the optical pick-up comprises a light source configured to generate the light beam, and at least one lens configured to compensate the light beam for aberration, and
the actuator is configured to move the at least one lens.

10. A method of controlling an optical disc apparatus, the method comprising:
rotating an optical disc having a recording surface for data;
emitting a light beam by an optical pick-up to the rotating optical disc; and
operating the optical pick-up to focus the light beam emitted from the optical pick-up to perform one of recording and reproducing the data on the recording surface and to track curvature of the recording surface within a preset allowable range, and processing the light beam reflected from the recording surface,
the processing the light beam comprising increasing the allowable range if it is determined that the focus of the light beam cannot track the curvature of the recording surface in a section of the recording surface.

11. The method according to claim 10 , wherein the processing the light beam comprises:
controlling the optical pick-up to adjust a position with respect to an optical axis of the light beam in response to a focus error signal that indicates an extent of deviation of the light beam from focus on the recording surface; and
determining that the focus of the light beam cannot track the curvature of the recording surface in the section if the focus error signal has an amplitude equal to or greater than a preset value.

12. The method according to claim 11 , wherein the processing the light beam comprises:
deriving a reproducing signal including a data recording pattern formed along a track of the recording surface based on the light beam reflected from the recording surface; and
determining that the focus of the light beam cannot track the curvature of the recording surface in the section if the focus error signal has an amplitude equal to or greater than the preset value and the reproducing signal shows the data recording pattern based on the reflected light beam.

13. The method according to claim 10 , wherein the increasing the allowable range comprises increasing the allowable range by increasing an operation speed of the optical pick-up with respect to a rotation speed of the optical disc.

14. The method according to claim 13 , wherein the optical disc apparatus comprises a shaft configured to support the optical disc and a spindle motor for driving the shaft, and
the increasing the operation speed of the optical pick-up with respect to the rotation speed of the optical disc comprises decreasing revolutions per unit time of the spindle motor.

15. The method according to claim 13 , wherein the increasing the operation speed of the optical pick-up with respect to the rotation speed of the optical disc comprises increasing a focus moving speed of the light beam.

16. The method according to claim 15 , wherein the optical disc apparatus comprises an actuator configured to adjust a focus height of the light beam by adjusting a position of the optical pick-up along an optical axis of the light beam, and
the increasing the focus moving speed of the light beam comprises increasing operation sensitivity of the actuator.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Kim Jae Hyun

Classifications

• G11B7/0948 Primary

  specially adapted for detection and avoidance or compensation of imperfections on the carrier, e.g. dust, scratches, dropouts (G11B7/095 takes precedence) · CPC title

• G11B7/13927 Primary

  during transducing, e.g. to correct for variation of the spherical aberration due to disc tilt or irregularities in the cover layer thickness · CPC title

• G11B21/02

  Driving or moving of heads · CPC title

• G11B19/2009

  Turntables, hubs and motors for disk drives; Mounting of motors in the drive (means for clamping of disk to turntable G11B17/022 and subgroups) · CPC title

• G11B7/0941

  Methods and circuits for servo gain or phase compensation during operation (for initialising servos G11B7/0945) · CPC title