Lg Electronics Inc.

Sungkyunkwan University

Hun Chul Seo

Jin Hong Kim

Jin Sung Kim

Seung Yoon Lee

Keum Cheol Kwak

Tae Hee Jeong

Jun Seok Lee

Kyung Chan Park

Seong Yun Jeong

Chang Ho Lee

Seoung Won Lee

Chul Kyu Kim

Chul Hwan Kim

Chang-Jong Kim

Sang Bong Rhee

Chul Moon Lee

Woon-Seng Yeo

Yun Tae Ko

Myong-Ryeong Kim

The reclosing control device configured to perform a reclosing control in case of a fault in a transmission line. Further, the reclosing control device includes a voltage detection unit configured to detect a faulted phase voltage waveform and extract a harmonic component contained in the faulted phase voltage waveform; a HR calculating unit configured to calculate ratio values between even harmonics and odd harmonics based on the extracted harmonic component; and a reclosing control unit configured to determine whether or not an arc is finally extinguished based on the calculated ratio value and perform a reclosing control depending on a result of the determination.

Method and device for reclosing control using a harmonic ratio

The present invention relates to a reclosing control system and method using a superconducting fault current limiter. The reclosing control system includes a superconducting fault current limiting device in which two circuits, each having a switch and a superconducting fault current limiter connected in series with each other, are connected in parallel with each other. A recloser is disposed between the superconducting fault current limiting device and a distribution line and is configured to control reclosing. The distribution line is connected to the recloser and is configured to transfer power to a load.

Reclosing control system and method using superconducting fault current limiter

The present invention is directed to an optical disk having a projection that prevents full contact of the upper surface of the disk when engaging a supporting surface. The optical disk includes a projection formed in a central portion of the optical disk that abuts or is near the upper surface of a protecting layer.

Optical disk having a projection with lateral inclined surface

An optical recording medium records information in a mechanism of generating new material, having reflectance different from that of others in information recording layer, when laser beam is projected thereonto. The optical recording medium includes a substrate, and a reflective layer positioned on the substrate to reflect an entering laser beam and having an information recording layer. The information recording layer includes a first information recording layer containing one or more elements selected from a group of Si, Ge, and Sb, and a second information recording layer containing one or more elements selected from a group of Si, Sb, Te, and Al. Data can be recorded in high density and the optical recording medium provides high recording stability and recording sensitivity.

Optical recording medium

An apparatus and method for testing mechanical endurance of a surface of an optical disc is disclosed, which includes a rotating plate on which the optical disc is fixed to generate scratch thereon, and rotating the fixed optical disc; and a plurality of abrasion wheels disposed in perpendicular to the rotating plate, and being in contact with the surface of the optical disc, to generate the scratch on the surface of the optical disc, wherein, the scratches generate when the optical disc rotates a predetermined turn, e.g. below ten turns for applying a predetermined load generated from the abrasion wheel on the optical disc.

Apparatus and method for testing mechanical endurance of surface of optical disc, the optical disc of same kind as the tested optical disc

A method for evaluating an anti-contamination level on a surface of optical recording medium is disclosed. The method includes forming an artificial fingerprint on the surface by contacting a stamp having an artificial material adhered thereto on an optical recording medium, and measuring a symbol error rate (SER) of the formed artificial fingerprint, to determine a sensitivity of the fingerprint and determining whether the optical recording medium is of good quality or bad quality depending upon the measured SER.

Method for evaluating anti-contamination level on a surface of optical recording medium, the apparatus and the optical recording medium

The disclosure includes a system, device, apparatus and programmed medium of measuring thickness of an optical disc by using an interference effect of the optical disc layer. Such a system can include: a spectroscope to separate light, reflected from a surface of an optical disc, into constituent frequencies thereof; an optical intensity measuring unit to measure intensities of the constituent frequencies, respectively, as a first spectrum of data; and a processor to do at least the following, convert the first spectrum data into a second spectrum of values that exhibits variation as a function wavelength and refractive index, transform the second spectrum using a Fast Fourier Transform, and detect a thickness of one or more of the spacer layer and the cover layer, respectively, based upon the transformed spectrum. The disclosed technologies have advantages for high precisely measuring thickness of an optical disc.

Technologies for measuring thickness of an optical disc

An apparatus and method for testing mechanical endurance of a surface of an optical disc are disclosed. The apparatus includes a rotating plate, on which an optical disc to be scratched is loaded, for rotating the loaded optical disc, and a plurality of abrasion wheels of a predetermined type, disposed at a perpendicular to the rotating plate, for contacting the optical disc and generating the scratch, the scratch being generated when the optical disc rotates a predetermined number of turns, e.g., maximum of 5 turns for the abrasion wheels to apply a predetermined load on the optical disc.

Apparatus and method for testing mechanical endurance of a surface of an optical disc

A method of measuring thickness of an optical disc by using an interference effect of the optical disc layer is disclosed. The method includes detecting an intensity of a reflective light according to a wavelength of a light as spectrum data for each wavelength, converting the detected spectrum data for each wavelength into a spectrum value as a function of a wavelength that a refractive index is reflected, and detecting a position where the intensity of the reflective light has a peak as a thickness of a spacer layer and a cover layer respectively by converting the converted value into a length of an interference area for representing a layer thickness of the optical disc by the Fast Fourier Transform. The disclosed method has advantages for high precisely measuring thickness of an optical disc.

Method for measuring thickness of an optical disc

An optical disk and a method of fabricating the optical disk capable of improving the signal quality and the productivity are disclosed. The optical disk includes a plurality of reflective layers stacked on a substrate, amorphous layers formed among the reflective layers which include a small amount of oxide therein, a recording layer, formed on the reflective layer, for recording information, and a cover layer formed on the recording layer.

Optical disk and method of fabricating the same

An apparatus and method for testing mechanical endurance of a surface of an optical disc are disclosed. The apparatus includes a rotating plate, on which an optical disc to be scratched is loaded, for rotating the loaded optical disc, and a plurality of abrasion wheels of a predetermined type, disposed at a perpendicular to the rotating plate, for contacting the optical disc and generating the scratch, the scratch being generated when the optical disc rotates a predetermined number of turns, e.g., a maximum of 5 turns for the abrasion wheels to apply a predetermined load on the optical disc.

An initialization method for a phase change type optical disc, including the steps of irradiating a laser beam of a predetermined power onto a specimen optical disc, increasing the power of the laser beam with constant rate, detecting a reflectivity of the laser beam reflected from the optical disc in accordance with the increasing laser power, detecting a saturated value of the reflectivity of the laser beam, detecting an optimal power of the laser beam where the reflectivity belongs 70% to 90% of the saturated value, and performing initialization by irradiating the laser beam having thus obtained optimal power onto the optical disc to be initialized which will be initialized with the adjusted laser beam can improve the recording characteristic and erase ratio.

Growing community of inventors

Gyeonggi-do, South Korea

Hun Chul Seo