Patent application number | Description | Published |
20090147642 | APPARATUS FOR AND METHOD OF DETECTING TRACKING ERROR SIGNALS - An apparatus for detecting a tracking error signal includes an optical detector to receive light beams reflected from an optical disc and having a plurality of detecting regions; and a phase difference extracting unit to extract a phase difference between a pair of optical signals output from the optical detector, wherein the phase difference extracting unit repeatedly moves a first graph representing one optical signal from among the pair of optical signals by a predetermined distance with respect to a second graph representing another optical signal from among the pair of optical signals, the first and second graph represent optical signal values with respect to t-axis, adds differences between optical signal values of the first graph and optical signal values of the second graph corresponding to predetermined positions of the t-axis, the adding differences is repeated for each of the repeatedly moved positions of the first graph, and outputs a moved distance of a position where the added value is smallest as a phase difference. | 06-11-2009 |
20100053710 | APPARATUS FOR RECORDING/REPRODUCING HOLOGRAPHIC DATA AND METHOD OF ADJUSTING POSITION OF RECORDING LAYER - An apparatus for recording/reproducing holographic data and a method of adjusting a position of a recording layer. While an objective lens focusing first and second lights having different wavelengths on a holographic data storage medium including first and second reflective layers reciprocatingly moves in a direction of an optical axis, a focus movement unit, which moves a focus of the second light in the direction of the optical axis until a time difference between a first detection signal generated when the first light is reflected from the first reflective layer and a second detection signal generated when the second light is reflected from the second reflective layer becomes a value corresponding to a position of a desired recording layer, is controlled to move a focal position of the second light so that the focal position of the second light can be adjusted to the position of a desired recording layer. | 03-04-2010 |
20100061203 | METHOD AND APPARATUS FOR RECORDING AND/OR REPRODUCING DATA INTO AND/OR FROM OPTICAL DISK - Provided are a method and apparatus for recording and/or reproducing data into and/or from an optical disk. The apparatus includes a reference beam optical system to form a focus of a reference beam in an optical data storage layer of the optical disk and including an objective lens; a signal beam optical system to form a focus of a signal beam in the optical data storage layer and also including the objective lens; and a servo optical system to project a servo beam onto the optical disk, receiving a reflection servo beam which is reflected on the optical disk, and performing focusing and tracking control on the objective lens. The reference beam optical system includes a first focus mover to move the focus of the reference beam, and the signal beam optical system includes a second focus mover to move the focus of the signal beam. The data is recorded into a plurality of recording layers in the optical data storage layer by moving a first focus position, at which the foci of the reference beam and the signal beam are located, in a thickness direction of the optical data storage layer, which is a focusing direction. | 03-11-2010 |
20100061210 | OPTICAL DISC AND RECORDING/REPRODUCING METHOD AND APPARATUS FOR THE OPTICAL DISC - An optical disc, and a recording/reproducing method and apparatus to record information on the optical disc. The optical disc includes an optical information storage layer, including a layer format region and a user data region. The layer format region is divided into virtual layers that are disposed at different depths. The virtual layers include layer information to distinguish the virtual layers from one another. | 03-11-2010 |
20100110846 | METHOD AND APPARATUS FOR CONTROLLING POSITION IN WHICH DATA IS TO BE RECORDED - A method and apparatus to control a position in which data is to be recorded on a holographic data recording medium by using interference between a reference light and a signal light, the method including: irradiating the reference light and the signal light on the holographic data recording medium; generating a focus error signal that indicates a distance difference between a first focus corresponding to a focus of the reference light on the holographic data recording medium and a second focus corresponding to a focus of the signal light on the holographic data recording medium, based on information about a reflective signal light generated when the irradiated signal light is reflected from a reflective transmission layer of the holographic data recording medium; and moving the second focus to a position of the first focus, based on the focus error signal. | 05-06-2010 |
20120326514 | POWER SUPPLY CONTROL APPARATUS AND POWER SUPPLY CONTROL SYSTEM HAVING THE SAME - A power supply control apparatus is connected to an electric device to control supply of power to the electric device. The apparatus includes a main power switch to apply or interrupt main power to the electric device, the main power being external input commercial AC power, an auxiliary power storage unit supplied and charged with the main power as auxiliary power, a charging/discharging unit including a charging circuit to convert the main power into DC power and charge the converted DC power in the auxiliary power storage unit, and a discharging circuit to convert the DC power in the auxiliary power storage unit into AC power and discharge the converted AC power to the electric device, and a controller to control the main power switch, and control the charging/discharging unit to selectively drive the charging circuit or the discharging circuit. | 12-27-2012 |
20140244094 | MOBILE ROBOT AND METHOD OF LOCALIZATION AND MAPPING OF THE SAME - A method of localization and mapping of a mobile robot may reduce position errors in localization and mapping using a plurality of vector field sensors. The method includes acquiring a relative coordinate in a movement space using an encoder, acquiring an absolute coordinate in the movement space by detecting intensity and direction of a signal using vector field sensors, defining a plurality of virtual cells on a surface of the movement space such that each of the cells has a plurality of nodes having predetermined positions, and updating position information about the nodes of the cells based on the relative coordinate acquired through the encoder and the absolute coordinate acquired through the vector field sensors and implementing localization and mapping in the movement space in a manner that position information of a new node is estimated while position information of a previous node is determined. | 08-28-2014 |
20150032259 | CLEANING ROBOT AND METHOD FOR CONTROLLING THE SAME - A cleaning robot includes a non-circular main body, a moving assembly mounted on a bottom surface of the main body to perform forward movement, backward movement and rotation of the main body, a cleaning tool assembly mounted on the bottom surface of the main body to clean a floor, a detector to detect an obstacle around the main body, and a controller to determine whether an obstacle is present in a forward direction of the main body based on a detection signal of the detector, control the rotation of the main body to determine whether the main body rotates by a predetermined angle or more upon determining that the obstacle is present in the forward direction, and determine that the main body is in a stuck state to control the backward movement of the main body if the main body rotates by the predetermined angle or less. | 01-29-2015 |