Abstract: A method and apparatus for compensating tilt. The tilt compensation method includes: obtaining one of a jitter best, an RF envelope, and a focus DC offset (FODC) from a detection signal of the ROM data region and determining whether the obtained value is within a tolerance range; and obtaining an initial skew compensation value using the obtained value when the obtained value is within the tolerance, changing the magnitude of current applied to an actuator designed to perform driving in at least three-axis directions to drive an objective lens of an optical pickup assembly in a radial tilt direction when the obtained value is not within the tolerance range, and repeating the obtaining of one of the jitter best, the RF envelope, and the FODC and changing the magnitude of the current until the obtained value is within the tolerance range.

Abstract: An optical pickup includes a light source which emits light, a grating which separates a portion of the light emitted from the light source, a reflecting member which reflects another portion of the light emitted from the light source, a monitoring photodetector disposed on a traveling path of the light reflected from the reflecting member and which measures the reflected light, an optical path changer which changes an optical path of the light separated by the grating, an objective lens light which condenses the light the optical path of which is changed onto a disc, and a signal detecting photodetector which receives the light reflected from the disc.

Abstract: A method and apparatus for compensating tilt. The tilt compensation method includes: obtaining one of a jitter best, an RF envelope, and a focus DC offset (FODC) from a detection signal of the ROM data region and determining whether the obtained value is within a tolerance range; and obtaining an initial skew compensation value using the obtained value when the obtained value is within the tolerance, changing the magnitude of current applied to an actuator designed to perform driving in at least three-axis directions to drive an objective lens of an optical pickup assembly in a radial tilt direction when the obtained value is not within the tolerance range, and repeating the obtaining of one of the jitter best, the RF envelope, and the FODC and changing the magnitude of the current until the obtained value is within the tolerance range.

Abstract: In a method and system for forming light beams onto a disc for a plurality of disc formats, a main beam is directed onto the disc. A side beam is directed onto the disc with a displacement from the main beam, with the displacement being a LCM (least common multiple) distance of respective track pitches for the plurality of disc formats. A tracking servo uses such main and side beams with stable operation for the plurality of disc formats.

Abstract: An optical pickup includes a light source which emits light, a grating which separates a portion of the light emitted from the light source, a reflecting member which reflects another portion of the light emitted from the light source, a monitoring photodetector disposed on a traveling path of the light reflected from the reflecting member and which measures the reflected light, an optical path changer which changes an optical path of the light separated by the grating, an objective lens light which condenses the light the optical path of which is changed onto a disc, and a signal detecting photodetector which receives the light reflected from the disc.

Abstract: An optical pickup actuator and an optical pickup using the same, wherein the optical pickup actuator has: a lens holder, on which an objective lens is mounted; and a tilt photodetector, which is installed in the lens holder and receives a portion of light used to record and/or to reproduce information on and/or from a recording medium according to a relative tilt between the objective lens and the recording medium. The optical pickup actuator moves the objective lens in a tracking direction, a focusing direction, and a tilting direction. The optical pickup actuator can detect both tilt of the recording medium and tilt of the objective lens using the tilt photodetector, so the optical pickup can be applied to an optical recording and/or reproducing apparatus of high-density and/or high-speed.

Abstract: A circuit protects a light element and prevents a breakdown of a laser diode (LD) when electric static discharge (ESD) occurs. The circuit protects the light element in a drive to control an operation of the light element, which radiates light onto a disc. Here, the drive includes a switch between an active node of the light element and a predetermined potential so that the switch is short-circuited in a normal state, but is open when the drive operates. The light element is protected from static electricity or a surge voltage in a manufacturing process thereof or under a user environment. As a result, the probability that the light element is broken down is remarkably reduced.

Abstract: A circuit protects a light element and prevents a breakdown of a laser diode (LD) when electric static discharge (ESD) occurs. The circuit protects the light element in a drive to control an operation of the light element, which radiates light onto a disc. Here, the drive includes a switch between an active node of the light element and a predetermined potential so that the switch is short-circuited in a normal state, but is open when the drive operates. The light element is protected from static electricity or a surge voltage in a manufacturing process thereof or under a user environment. As a result, the probability that the light element is broken down is remarkably reduced.