Abstract: An optical pickup apparatus and an optical recording/reproducing system including the same, the optical pickup apparatus includes at least two optical systems for different types of optical recording media, one of objective lenses of the optical systems being offset from a central line of the optical recording medium, wherein the optical system including the offset objective lens having a diffraction grating diffracting light emitted from a light source to form a main beam and sub-beams, wherein the diffraction grating includes first and second diffraction regions having different grating patterns arranged alternately thereon, and a center of each sub-beam is arranged at a boundary of the first and second diffraction regions of the diffraction grating, and a center of the diffraction grating and an optical axis of the light source are adjusted to be coincided with each other, preventing generation of an alternating current in a Push-Pull signal of the sub-beams.

Abstract: A compatible optical pickup including an optical unit and a focusing unit. The optical unit emits a short wavelength light for high-density recording media and a long wavelength light for low-density recording media, directs the short and long wavelength light to a recording medium, receives lights reflected by the recording medium, and detects an information reproduction signal and/or an error signal from the received lights. The focusing unit focuses light received from the optical unit to form a light spot on a recording surface of the recording medium, diffracts the short wavelength light into a zero order light and the long wavelength light into a second order light to be used as effective light for recording and/or reproduction. Thus, a high-density recording medium and a low-density recording medium having different thicknesses can be compatibly used.

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.