Funai Electric Company Ltd.

Futoshi Takeda

Kenichi Fujita

Fuminori Tanaka

Toshiaki Fukui

Mika Hamaoka

Kazuki Kajikawa

Kenji Tanehashi

Kazuto Kitagawa

Kazuhiro Ichikawa

A mirror drive portion which causes a mirror portion to swing around a predetermined swing axis; a single optical sensor including a single light emission portion and a single light reception portion which receives light emitted from the light emission portion; a light blocking portion which is arranged in the mirror portion to swing together with the swing of the mirror portion and periodically blocks the light emitted from the light emission portion along with the swing; and a mirror control portion which controls the swing of the mirror portion based on an alternating voltage and a detection signal of the optical sensor, wherein the mirror control portion acquires a state of the swing of the mirror portion based on a light reception state of the light reception portion and a zero-cross timing of the alternating voltage, and controls the swing of the mirror portion.

Optical scanner unit and optical apparatus

An optical scanner unit includes a mirror component, a vibration generator, an optical sensor, and a light shield portion. The mirror component includes a reflective portion for reflecting light. The vibration generator swings the mirror component around a specific swing axis when AC voltage is applied. The optical sensor includes a light emitter and a light receiver for receiving light emitted from the light emitter. The light shield portion is provided to the mirror component so as to swing along with the mirror component. The light shield portion blocks the light emitted from the light emitter. The light receiver further includes a first light receiver that is provided on one swing angle side from a center position of a swing angle range of the light shield portion, and a second light receiver that is provided on the other swing angle side from the center position of the swing angle range.

Optical scanner unit and optical device

The present invention aims for shortening a time required before the focus control is started. The initial focus position is detected, while the optical disc is not rotated, by making the objective lens approach to the optical disc from the first separation position farther from the optical disc than the focus position. The focus control is performed so that the objective lens tracks the focus position of the data recording layer, while the optical disc is rotated, by making the objective lens approach to the optical disc after the objective lens is returned to the second separation position farther from the optical disc than the first separation position. The initial focus position can be focus position of the data recording layer. The second separation position can be a position farther from the optical disc by a predetermined distance than the initial focus position.

Optical disc device and focus control method thereof

An optical disk device includes an optical pickup that directs light beams onto a recording surface of an optical disk and receives reflected light, a signal generating unit that generates playback signals based on reflected light received by the optical pickup, an equalizer adjustment unit that performs equalizer adjustment of the playback signals, and an adjustment control unit. The adjustment control unit controls the equalizer adjustment unit so as to perform equalizer adjustment of the playback signals according to the playback signals based on reflected light from a management information area on a recording surface of the optical disk, the management information area including predetermined management information recorded thereon.

Optical disk device and equalizer adjustment method

Before tracking control is turned on, there is determined a correction formula for correcting a balance value of a tracking error signal depending on a position of a movable lens for spherical aberration correction. Then, after the tracking control has been turned on, using an RF signal as an index, the adjustment of the position of the movable lens for spherical aberration correction is performed, while the balance value of the tracking error signal is corrected by use of the correction formula. An adjustment value for adjusting the balance value of the tracking error signal at a time point of completing the adjustment of the position of the movable lens for spherical aberration correction is stored.

Optical disc apparatus

An optical disk device is configured such that when an optical disk including three or more recording layers on one side is inserted into the optical disk device, a movable lens position adjustment device performs adjustment using as an index a tracking error signal provided with a limit to an amount of movement of a movable lens for spherical aberration correction at start-up of the optical disk device and sets an upper limit to the number of retries of the adjustment at the recording layer farthest away from the side on which the laser beam is incident to 1 or more.

Optical disk device

Even when a first differentiation value is equal to or greater than a first threshold value, this optical disc device does not confirm 'CD' to be the differentiation result, as long as a first focus error signal FEor a first focus sum signal FSis less than a second threshold value; and even when the first differentiation value is equal to or greater than a second differentiation value, this optical disc device does not confirm 'CD' to be the differentiation result, as long as the signal FEis less than a second focus error signal FE, or as long as the signal FSis less than a second focus sum signal FS. The signals FEand FSare obtained when a CD laser beam is directed onto an optical disc. The signals FEand FSare obtained when a DVD laser beam is directed onto the disc.

Optical disc device

An optical disc device includes: a first searching part which searches a condition where amplitude level of a TE signal is made maximum by changing either one of position of a movable lens and a focus balance value in a state where a focus servo control is performed based on a FE signal; an adjusting line setting part which sets an adjusting line that has an inclination &#x3b1; which is preliminarily stored in a memory portion and that passes the position of the movable lens and the focus balance value both of which are searched by the first searching part; and a second searching part which changes the position of the movable lens and the focus balance value to plural values on the adjusting line in a state where the focus servo control is performed consecutively to search a condition where the amplitude level of the tracking error signal is made maximum.

An optical pickup has a photo detector which is divided into first, second, third and fourth quadrants, receives a laser beam reflected from an optical disc via an objective lens, and outputs first, second, third and fourth detection signals from the respective quadrants. A system controller controls a memory to store levels (A, B, C and D) of the first, second, third and fourth detection signals after a focus servo section performs a focus operation by shifting the objective lens in a direction perpendicular to the optical disc surface, and then, calculates a ratio of ((A+D)/(B+C)) in a radial direction of the optical disc. The system controller controls the tracking servo section to perform a tracking operation to shift the objective lens in the radial direction based on a correction table which represents a relationship between correction amount of the lens shift and the calculated ratio ((A+D)/(B+C)).

Optical disc recording and reproducing apparatus

A disc apparatus which can judge accurately whether or not a spindle motor is at fault due to a short circuit is provided. A disc apparatus () includes a spindle motor () which rotates a disc (), a differential operational amplifier () which successively detects output voltages of the spindle motor (), and a failure judgment unit () which calculates an average voltage of the plural output voltages and judges whether or not the spindle motor () is at fault in accordance with the average voltage and the output voltages. When counting number of occurrences of a specific state which indicates that one of the two output voltages detected successively is larger than the average voltage and other of the two output voltages is smaller than the average voltage, the failure judgment unit () judges that the spindle motor () is at fault. Consequently, the failure judgment unit () can rapidly and accurately judge the failure in the spindle motor () without the influence from the unexpected change of the output voltages.

Disc apparatus

An objective lens is raised from below upwards with a DVD laser diode turned on and levels of detection signals A, B, C, and D from a four segment photodetector are acquired and stored in a RAM. A ratio (A+D)/(B+C) in a direction of the X-axis is then calculated. When the ratio exceeds a predetermined value, a lens shift correction amount is calculated for the calculated ratio based on a correction table. The objective lens is then shifted in the direction of the X-axis in accordance with the calculated lens shift correction amount. These processes are executed before a series of processes required for achieving a focus-on state.

Optical disc reproducing apparatus

An optical disk apparatus includes: a servo control unit, operable to execute a servo control of focusing based on a focus error signal and to execute a servo control of tracking based on a tracking error signal; a detrack regulating unit, operable to execute a detrack regulation for setting an offset voltage, which is to be added to the tracking error signal, to be a voltage for giving the highest signal quality of an output of an optical pickup; and a defocus regulating unit, operable to execute a defocus regulation for setting an offset voltage, which is to be added to the focus error signal, to be a voltage for giving the highest signal quality of the output of the optical pickup. The defocus regulation is executed in a state in which the servo control of the focusing and the servo control of the tracking are executed. The defocus regulation is executed after the detrack regulation is executed, in the state in which the servo control of the focusing and the servo control of the tracking are executed.

Optical disk apparatus for carrying out a defocus regulation

An optical disk apparatus includes: a servo controller, operable to carry out a servo control of tracking of an optical pickup based on a tracking error signal; a TE balance regulator, operable to detect a TE balance correction value for equalizing, with a reference voltage, a central voltage of the tracking error signal when a beam spot of the optical pickup crosses a track; a detrack regulator, operable to detect a detrack correction value for causing signal quality of an output of the optical pickup to be the highest; and a TE offset corrector, operable to set an offset voltage, which is to be added to the tracking error signal, to be the TE balance correction value when a difference between the TE balance correction value and the detrack correction value is smaller than a predetermined value, and to set the offset voltage to be a value between the TE balance correction value and the detrack correction value when the difference is greater than the predetermined value.

Optical disk apparatus

An optical disk device includes a pickup head, a thread motor, and a drive controller, and a thread drive IC. The drive controller supplies directed voltage to the thread drive IC. The thread drive IC in response supplies drive voltage to the thread motor, which moves the pickup based on the drive voltage from the thread drive IC. The drive controller directs to the thread drive IC supply of first directed voltage. The thread drive IC supplies first supplied voltage to the thread motor in response to the directive from the drive controller to supply the first directed voltage. The drive controller detects the first supplied voltage and calculates a correction value based on the detected first supplied voltage. The drive controller corrects the directed voltage with the correction value and then directs to the thread drive IC supply of a corrected drive voltage.

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Osaka, Japan

Futoshi Takeda