Optical disc apparatus
AssigneeRenesas Electronics Corporation
InventorMasanori Ogura
Life of this patent
Estimating the term…
Abstract
A simple circuit configuration allows an optical disc apparatus to reduce a problem of sound skips occurring due to damage on an optical disc. To this end, an LPF extracts a low-frequency component from a tracking actuator drive signal obtained by a tracking actuator driver. When the optical disc apparatus reads and writes information to and from the optical disc, a sled drive signal supplier outputs a sled pulse signal, as a drive signal for a sled motor, for a set-up predetermined time within each interval of a predetermined length, the sled pulse signal having a level corresponding to a level of the low-frequency component obtained by the LPF. On the other occasions, the sled drive signal supplier outputs the low-frequency component obtained by the LPF as the drive signal for the sled motor.
Claims18
An optical disc apparatus using an optical disc as an information recording medium, said optical disc apparatus comprising:
- an optical pickup;
- a tracking servomechanism that generates a tracking actuator drive signal on a basis of a tracking error signal obtained from the optical pickup, and controls a position of an objective lens included in the optical pickup;
- a sled motor that rotates and thereby moves the optical pickup in a radial direction;
- a low-pass filter that extracts a low-frequency component of the tracking actuator drive signal;
- and
- a sled drive signal supplier that compares a level of the low-frequency component with a predetermined level to generate a sled pulse signal for controlling a sound skip of the optical disc, and outputs the sled pulse signal as a drive signal for the sled motor, the sled pulse signal having a level corresponding to the level of the low-frequency component,
- wherein the sled drive signal supplier comprises:
- a comparator that compares the level of the low-frequency component with the predetermined level;
- a pulse level setting circuit that selects a first pulse level based on a result of the comparing indicating that the level of the low-frequency component is lower than the predetermined level, and selects a second pulse level based on the result of the comparing indicating that the level of the low-frequency component is equal to, or higher than the predetermined level, the second pulse level being higher than the first pulse level;
- a pulse generating circuit that generates the sled pulse signal having the level corresponding to a result of the selecting by the pulse level setting circuit;
- and
- a terminal outputting the drive signal, and
- wherein the optical disc apparatus further comprises a control circuit that switches a connection route between the low-pass filter and the terminal, the connection route including a first connection route indicating a route between the low-pass filter and the terminal includes the pulse generating circuit, and a second connection route indicating the route between the low-pass filter and the terminal does not include the pulse generating circuit.
An optical disc apparatus using an optical disc as an information recording medium, said optical disc apparatus comprising:
- a sled motor that rotates to move an optical pickup in a radial direction;
- a tracking servomechanism that generates a tracking actuator drive signal on a basis of a tracking error signal obtained from the optical pickup;
- a low-pass filter that extracts a low-frequency component of the tracking actuator drive signal;
- a sled drive signal supplier that comprises a terminal outputting a drive signal generated based on the low-frequency component, and further comprises a sled pulse outputting circuit that compares a level of the low-frequency component with a predetermined level to generate a sled pulse signal having a level corresponding to the level of the low-frequency component;
- a sled motor driver that drives the sled motor based on the drive signal;
- and
- a control circuit that switches a connection route between the low-pass filter and the terminal, the connection route including a first connection route indicating a route between the low-pass filter and the terminal includes the sled pulse outputting circuit, and a second connection route indicating the route between the low-pass filter and the terminal does not include the sled pulse outputting circuit.
Dependencies are inferred from the claim text.