Samsung Electronics Co., Ltd.

Byung-in Ma

In-sik Park

Byoung-ho Choi

Chong-sam Chung

Seong-sin Joo

Kyung-geun Lee

Jung-wan Ko

Tae-yong Doh

Jae-seong Shim

Joong-eon Seo

Jang-hoon Yoo

Tatsuhiro Otsuka

Du-seop Yoon

Yong-Jin Ahn

Joong-Eon Seo

Jin-hoon Jeon

Kwan-joon Kim

Chang-jin Yang

Young-man Ahn

Young-Man Ahn

Hea-jung Suh

Sung-ro Go

Pyong-yong Seong

Tae-Kyung Kim

Yong-jae Lee

Seok-jung Kim

Jong-bae Kim

Soo-yul Jung

Tae-youn Lee

Jong-koog Lee

Yong-kwang Won

Byung-ho Choi

Young-jin Ahn

Tae-yeon Lee

Gi-bong Song

Dmytro Kelbas

An apparatus for recording data on and reproducing data from the disk in which a recording area is divided into sectors, includes a reproducing signal generator for generating a reproducing signal including sum signals Vand Vof radial pairs, a sum signal RF_sum, and a push-pull signal RF_pp from an optical signal reflected from the disk, a header area detector for generating a header area signal including a header area from the reproducing signal, a first synchronous signal level detector for detecting a magnitude Ivfoof a first synchronous signal in the first header by being synchronized with the header area signal, a second synchronous signal level detector for detecting a magnitude Ivfoof a second synchronous signal in the second header by being synchronized with the header area signal, and a balance calculator for calculating the balance of the magnitude Ivfoand the magnitude Ivfo

Method for detecting servo error, apparatus therefor, disk which maintains quality of servo error signal, method of controlling servo of disk recording/reproducing apparatus, method of detecting tracking error, and method of detecting tilt error

A compatible optical pickup compatibly using a high density recording medium and at least one low density recording medium, includes an objective lens to form a light spot suitable for use on a recording surface of the high density recording medium by focusing a corresponding incident light beam with a high NA suitable for the high density recording medium and a light spot suitable for use on another recording surface of the low density recording medium by focusing another corresponding incident light beam, and an actuator provided to apply tilt to the objective lens. The light beam for the low density recording medium is incident on the objective lens as a divergent beam. When the objective lens is shifted in a radial direction, a tilt is applied to the objective lens corresponding to the shift.

Compatible optical pickup applying tilt to objective lens in proportion to radial movement of objective lens

A method of, and an apparatus for detecting a radial tilt of a disc. Phases of summed signals obtained from signals that external light-receiving units of an octant photo diode receive are compared to generate an external phase comparison signal Do. Phases of other summed signals obtained from other signals, that internal light-receiving units of the octant photo diode receive, are compared to generate the internal phase comparison signal Di. The radial tilt is detected based on the internal and external phase comparison signals Di and Do obtained when a laser beam crosses a track formed the disc. Thus, the radial tilt can be more precisely detected.

Method and apparatus for detecting radial tilt

A method and apparatus for tracking error detection in an optical disk reproduction system. The tracking error detecting apparatus generates a tracking error signal as a difference signal of optical detection signals generated by more than two optical detectors positioned along a diagonal line from a track center and includes binarizers which binarize each output of the optical detectors, phase locked loops (PLLs) which generate respective clock signals synchronized with the outputs of each of the binarizers, a phase difference detector which detects a phase difference between the synchronized signals output from the PLLs, and low-pass filters which filter the output of the phase difference detector to output the result as the tracking error signal. The tracking error detecting apparatus generates a tracking error signal which is not dependent on the lengths of pits or marks recorded on an optical disk, enhancing the reliability of the tracking error signal.

Method and apparatus for tracking error detection in optical disk driver

A recording and/or reproducing apparatus and a method of controlling the same. The method of controlling the apparatus for recording information in or reproducing information from a disc having a wobbled track, the method includes detecting a wobble signal recorded in the wobbled track, and removing an error component occurring during the recording or the reproducing, based on the detected wobble signal. Accordingly, errors arising from a variety of factors can be accurately compensated for during a recording or reproducing operation.

Recording and/or reproducing apparatus and method of controlling the same

An optical pickup apparatus includes a first light source to emit a first light beam having a predetermined wavelength, a first optical path changer to change a proceeding path of the first light beam, an objective lens to focus the first light beam on a recording medium, a diffraction member to divide the first light beam reflected by the recording medium into five light regions, the diffraction member having a first diffraction region having a wide width in a direction corresponding to a tangential direction of the recording medium and second through fifth diffraction regions sequentially arranged around the outside of the first diffraction region in a direction corresponding to a radial direction of the recording medium, and a first photodetector having first through fifth light receiving portions to receive the first light beam reflected by the recording medium.

Optical pickup apparatus and optimal light spot focusing method

A physical identification data (PID) addressing method using a wobble signal, a wobble address encoding circuit, a method and circuit for detecting the wobble address and a recording medium therefor. Groove address information indicating physical identification information is phase modulated using a wobble clock signal and recorded in one of the two walls of a groove track, and land address information is phase modulated using a wobble clock signal obtained by shifting the phase of the former wobble clock signal and recorded in the other wall. That is, address information is phase modulated and recorded in each track using the wobbles having a phase difference of 90&#xb0; between adjacent tracks so that a sum of wobble signals from the adjacent tracks can be a quadrature phase shift keying (QPSK) signal. Therefore, more data can be recorded in the recording medium, and since an interval in which a wobble signal disappears is not caused, recovery of a wobble clock signal can be advantageously performed.

Physical identification data addressing method using wobble signal, wobble address encoding circuit, method and circuit for detecting wobble address, and recording medium thereof

An adaptive focusing apparatus and method thereof of an optical disc drive having a focus servo controller moves a pickup head to an optimal focus point. A disc driver rotates an optical disc and includes a reflected signal detector detecting a signal reflected from the optical disc by the pickup head and a signal processor preventing spikes between a surface of the optical disc and the pickup head in response to the reflected signal and generating a focus drive signal for the focus servo controller using an adaptive focus search algorithm. The algorithm includes a static part and a dynamic part to reduce a focus search time. Accordingly, damage to the optical disc due to spikes between the surface of the optical disc and the pickup head can be prevented and a focus search time can be reduced.

Adaptive focusing method and apparatus

An error signal detection method includes detecting light incident through an objective lens after having been reflected and diffracted from a recording medium, as eight light portions in a matrix including four inner light portions and four outer light portions, wherein the rows and columns of the matrix are parallel to the tangential and radial direction of the recording medium, respectively; calculating a first sum signal by summing a detection signal from at least one outer light portion located in a first diagonal direction, and a detection signal from an inner light portion located in a second diagonal direction; calculating second sum signal by summing a detection signal from an inner light portion located in the first diagonal direction, and a detection signal from an outer light portion located in the second diagonal direction; and comparing phases of the first and second sum signals to detect a tilt error signal.

Error signal detection apparatus and method for optical recording/reproducing system

A method of and a circuit for providing a playback signal, which is compensated for time delay, from a photodetector having a plurality of outputs. A time difference between a first signal corresponding to a part of the outputs of the photodetector and a second signal corresponding to another part of the outputs of the photodetector is detected and one of the first and second signals is temporally shifted to compensate for a time delay between different outputs of the photodetector. The temporally shifted signal is summed with the other signal to provide a playback signal. Accordingly, the time delay between the outputs of the photodetector is compensated, thereby increasing the degree of modulation of the data playback signal. In addition, distortion or degradation of the signal is suppressed and occurrence of errors in the playback signal is minimized, thereby improving the reliability of the playback signal.

Method and circuit for detecting playback signal which is compensated for time delay

A method of detecting a servo error, an apparatus therefor, a disk which maintains quantity of a servo error signal, a method of controlling a servo of an apparatus for recording data on and reproducing data from a disk, a method of detecting the tracking error, and a method of detecting tilt error of the apparatus. The apparatus for recording data on and reproducing data from the disk in which a recording area is divided into sectors, each sector has a header for indicating an address, each header has a first header and a second header which are recorded to deviate from the center of the track in opposite directions, and the first header and the second header have address areas in which the addresses of sectors are recorded and synchronous signal areas in which synchronous signals for detecting the address signals recorded in the address area are recorded, includes a reproducing signal generator for generating a reproducing signal including sum signals Vand Vof radial pairs, a sum signal RF_sum, and a push-pull signal RF_pp from an optical signal reflected from the disk, a header area detector for generating a header area signal including a header area from the reproducing signal received from the reproducing signal generator, a first synchronous signal level detector for receiving the output of the reproducing signal generator and detecting a magnitude Ivfoof a first synchronous signal in the first header by being synchronized with the header area signal received from the header area detector, a second synchronous signal level detector for receiving the output of the reproducing signal generator and detecting a magnitude Ivfoof a second synchronous signal in the second header by being synchronized with the header area signal received from the header area detector, and a balance calculator for calculating the balance of the magnitude Ivfoof the first synchronous signal detected by the first synchronous signal level detector and the magnitude Ivfoof the second synchronous signal detected by the second synchronous signal level detector. As a result, it is possible for the recording/reproducing apparatus to stably control a servo therein and maintain an optimal recording/reproducing state since the apparatus for detecting the servo error correctly detects the servo error state of the disk.

METHOD FOR DETECTING SERVO ERROR, APPARATUS THEREFOR, DISK WHICH MAINTAINS QUALITY OF SERVO ERROR SIGNAL, METHOD OF CONTROLLING SERVO OF DISK RECORDING/REPRODUCING APPARATUS, METHOD OF DETECTING TRACKING ERROR, AND METHOD OF DETECTING TILT ERROR

An optical recording/reproducing apparatus and method to determine a type of disk including a photodetector divided into at least two light receiving sections in a radial direction. A radial subtractor generates a radial push-pull signal from a difference between light receiving signals from a disk and received by the at least two light receiving sections, where the disk includes one of a first disk and a second disk. An upper envelope detector detects an upper envelope signal from the radial push-pull signal and a lower envelope detector detects a lower envelope signal from the radial push-pull signal. A phase comparator detects a phase difference between the upper envelope signal and the lower envelope signal. A type of disk determiner distinguishes the first disk from the second disk according to a magnitude of the phase difference and outputting a signal indicative thereof, where the second disk includes a density higher than the first disk. A servo error generator and servo controller receives the magnitude of the phase difference and the light receiving signals and outputting servo error signals. A servo driver amplifier receives the servo error signals to output a voltage to drive a spindle motor of the disk. Furthermore, a first track cross signal generator generates a first track cross signal from an envelope of an RF SUM signal, wherein the RF SUM signal is obtained by adding the light receiving signals. A second track cross signal generator generates a second track cross signal from an envelope of the radial push-pull signal. A switch selectively outputs one of the first track cross signal and the second track cross signal according to the output signal from the type of disk determiner.

Method and apparatus for determining a type of disk

An apparatus to generate a seek direction detecting signal for an optical pickup to determine a position of a center of an optical spot focused on an optical disk relative to a center of a track, which focuses a main beam on a first optical detector and a sub-beam having a predetermined aberration in a radial direction on a second optical detector using a light dividing unit. The second optical detector has an inner and an outer pair of light receiving portions arranged along the radial direction, the inner pair being between the outer pair. A signal processing portion includes a first signal processing portion to detect a track error signal from signals output from the first optical detector, and a second signal processing portion to generate the seek direction detecting signal from signals detected by the second optical detector and the track error signal.

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Suwon, South Korea

Byung-in Ma