Hitachi, Ltd.

Hitachi-lg Data Storage, Inc.

Other

Hitachi Video and Information System, Inc.

Jvc Kenwood Corporation

Hitachi Video and Information Systems, Inc.

Toru Kawashima

Toshimitsu Kaku

Atsushi Yamada

Hisataka Sugiyama

Tsuyoshi Toda

Koichiro Nishimura

Tetsuya Fushimi

Seiichi Mita

Takehiko Sekine

Mitsuru Harai

Masanori Matsuzaki

Tomoya Hoshi

Yosiho Suzuki

Motoyuki Suzuki

Nobuo Kawamura

Yoshio Suzuki

Norihiro Hara

Hiroyuki Tsuchinaga

Takuya Mizokami

Masahiro Takasago

Takeyoshi Kataoka

Hiroharu Sakai

Hiroyuki Minamura

Osamu Nakayama

Hisamitsu Tanaka

Mitsuhiro Nishidate

Noritaka Narita

Akira Takagishi

Toshiharu Kon

The wireless device includes: a frequency setting unit which sets a frequency; a first frequency display unit which displays the set frequency as a set-up frequency in numbers; and a second frequency display unit which draws at least one predetermined frequency range, centering the set-up frequency, on a scale having a fan shape by interlocking the at least one predetermined frequency range with the setting of the frequency performed by the frequency setting unit. Here, the scale is rotated about a virtual center point having the fan shape of the scale, and a center of the scale is shown to always correspond to the set-up frequency.

Wireless device and method of displaying frequency

An optical disc apparatus capable of improving an overwrite performance for performing an overwrite operation on a re-writable type optical disc. The apparatus includes a calculating section which calculates out a recording power at the time of previously performing recording in a recording area of the optical disc, and a recording power determining section which determines a write power of the recording power calculated out by the calculating section as a write power of the currently recorded recording power, and at the same time, adjusts erase power, cooling power, and/or middle power of the recording power calculated out by the calculating section to finally determine the currently recorded recording power.

Optical disc apparatus and method for controlling overwrite power

Test writing is executed while skipping areas where deviations are present on an optical disk to thereby improve accuracy and reliability of an optimum recording condition to be derived. A deviation detecting unit detects the deviations of a guide groove on the optical disk on the basis of a fluctuation amount of a focus error signal or a tracking error signal, and registers information of the detected deviations onto a memory. A test writing processing unit refers to the memory, and records and reproduces a test signal while skipping the areas where the deviations are detected.

Optical disk apparatus and test writing method

In a method for adjusting a focus position for an optical disc, onto/from which in formation is recorded or reproduced, while adjusting the focus position of an optical reproducing means, upon a recording surface of an optical information recording medium having an area where information of the optical information recording medium is recorded in advance, comprising the following steps of: memorizing plural numbers of information relating to focus positions determined appropriately, which can be obtained from the area where the information of the optical information recording medium is recorded in advance; and adjusting the focus position for the optical disc loaded into an apparatus, from at lease one (1) signal relating to the focus position, which can be obtained from the optical disc, with utilizing a relationship between the plural numbers of information relating to the focus positions determined appropriately, memorized in advance, when reproduction of the information is impossible when the optical disc is loaded into the apparatus, thereby providing the focus position adjusting method and an optical disc apparatus applying the same therein, for enabling an appropriate focus adjustment even in case when DMA area cannot read out due to damages or defects therein.

Method for adjusting a focus position on an optical disc and an optical disc apparatus applying the same therein

A focus-servo control method of an optical disc recording/reproducing apparatus, for recording or reproducing information onto/from an optical disc having a track with a land and a groove, which are formed in a spiral manner on an information recording surface thereof, the optical disc recording/reproducing apparatus including an objective lens, the method comprising steps of: moving an optical spot from the land to the groove or from the groove to the land through a L/G exchange portion therebetween and moving a position of the objective lens from a land position to a groove position by gradually changing a focus offset value for the land to a focus offset value for the groove from a position located before the L/G exchange portion, when the optical spot moves from the land to the groove.

Optical disc recording/reproducing apparatus and focus-servo method thereof

This invention provides a method of controlling switching of computers according to a cause of failure without preparing one standby node for each active node. For n active nodes (), m standby nodes () of different characteristics (in terms of CPU performance, I/O performance, communication performance, and the like) are prepared. The m standby nodes () are assigned in advance with priority levels to be failover targets for each cause of failure. When a failure occurs in one active node (), a standby node that can remove the cause of the failure is chosen out of the m standby nodes () to take over data processing.

Computer system management method, management server, computer system, and program

In the present invention, the processing sequence of a microprocessor for restructuring the recording parameters when changing the recording in an optical disk recording apparatus from a constant angular velocity (CAV) mode to a constant linear velocity (CLV) mode is as follows: (1) interrupt the recording process; (2) calculate a linear velocity at a point where the recording linear velocity becomes constant; (3) calculate a third recording parameter in the linear velocity by a linear interpolation based on first and second recording parameters which are corrected by test writing, replacing all the recording parameters for an outer circumference of an optical disk from a radius position where the linear velocity becomes Cx, with the third recording parameter; and (4) restart the recording with the third recording parameter as a recording condition.

Recording control method for optical disk recording apparatus and optical disk recording apparatus

Means is provided that produces stabilized trial write results when, for example, servo misalignments are caused due to deviations on an optical disc that requires trial writes at high linear velocity. A recording method produces a recording parameter in the event of recording information into an arbitrary address position in the manner that a recording parameter is obtained through a predetermined calculation method from the results of learning of recording parameters on two or more zones of the optical disc where the linear velocities are different form one another. In a zone where the linear velocity is low, the method determines an optimal recording parameter from a jitter value of a reproduced signal waveform generated in a trial write. In a zone where the linear velocity is high, the method determines an optimal recording parameter in accordance with information obtainable from an amplitude value of a reproduced signal generated in a trial write.

Optical information recording method and optical information recording apparatus

A beam is irradiated to an information recording medium having land tracks and groove tracks alternately formed on a track formed in turn on an information recording surface thereof and pre-pits so pre-formatted as to deviate from the center of the track, a return beam of the irradiated beam is received by detectors split into two parts in a track direction to obtain a differential signal, the pre-pit is detected from this differential signal and control of recording and reproducing processings is executed by using the pre-pit detection signal so obtained as the reference.

Method for recording and reproducing information by pre-pits detection

Method and apparatus for recording/reproducing by pre-pits detection

For a disk of a land/groove scheme with land tracks and grooves appearing alternately, in order to enable stable and reliable reproduction of information as recorded on a disk by stably and reliably detecting a specific position at which a land track and groove change therebetween, a technique is employed for detecting the position whereat one land track is changed to a groove, or vice versa, by utilizing an HPP signal rather than an RF signal in cases where an optical head 103 attempts to reproduce certain information at the pit formation position of a disk 101. In addition, detect the polarity--positive or negative--of a pit signal appearing in the HPP signal, and then detect the position whereat the land track and groove change therebetween based on the position at which the order or sequence thereof changes, thereby permitting effectuation of optical head's tracking control and focus control by a method suitable for its respective parts.

Method and apparatus for detecting position of alternated land and

An information reproducing apparatus is capable of stably and correctly binarizing a signal reproduced from a recording medium, such as an optical disk, even if the reproduced signal contains a fluctuation of its low frequency component. The reproduced signal is replaced by an AC signal in a period other than a period during which the reproduced signal is to be demodulated so that DC fluctuation of the reproduced signal is reduced to thereby stably and correctly binarize the reproduced signal.

Information reproducing apparatus with a DC level correcting capability

A PLL circuit produces a synchronous signal by utilizing a regenerative clock signal in a VFO portion in a regenerative signal which was read out from a recording medium in sections. When a defective portion is present in a regenerative clock signal, the same sector is read out again from the recording medium to obtain the regenerative signal. A loop gain of the PLL circuit is made to be low in the defective portion of the regenerative signal which was read out again, thereby to prevent the synchronous fault of the PLL circuit due to the defective portion.

Apparatus for reproducing data from a regenerative signal using a PLH

A signal reproducing system discriminates signals stably in the case of reproducing a signal from an optical recording medium which has coexistent recording areas with the signals recorded in different recording forms therein. Parts that constitute a reproduced signal are respectively derived by corresponding signal detectors from the optical recording medium in which a preformat area and a data area are included as the coexistent recording areas. The average potentials of VFO parts, which are respectively contained in the reproduced signal parts, are detected on the basis of the envelopes of the signal parts by a peak detecting circuit and a bottom detecting circuit. The detected average potentials are compared with a reference voltage, and the resulting difference potentials are added to the reproduced signal by an adder to bring the average potentials of the VFO parts into agreement. Further, an unwanted part of the output signal of the adder corresponding thereto is replaced by a switch with the output signal of a signal generator, which has an average potential equal to the average potential of the VFO parts brought into agreement.

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Mito, Japan

Toru Kawashima