Abstract: The present disclosure includes systems and techniques relating to writing ramp-tracks on a computer readable medium. In some implementations, a trajectory is identified across previously written tracks on a surface of a machine-readable medium for a read-write head to move along and build up velocity. Identifying the trajectory includes identifying one of the previously written tracks as a launch location from which to launch the read-write head. Identifying the trajectory also includes identifying a start writing location near a blank region of the surface of the machine-readable medium at which to turn on a write gate. A current is applied to the read-write head to cause the read-write head to move along the trajectory. In addition, the identified launch location is adjusted until a target velocity is obtained at the start writing location.

Abstract: A highly reliable optical pickup which is not likely to collide with an optical disk is provided. Relative positions of two objective lenses 100 and 101 (along a focus direction) on a lens holder 102 are determined so that, while the objective lens 101 having a longer working distance is focused on an optical disk 200, the objective lens 100 having a shorter working distance and a protective member 103 are at positions which are more distant from the optical disk 200 than a height h of a protrusion which is present in an inner peripheral region of the optical disk optical disk 200.

Abstract: A method and apparatus for manufacturing an optical disk master and an optical disk, including measuring the reflectance of laser light at each of a plurality of radius positions by applying the laser light to an optical disk master-forming substrate provided with an inorganic resist layer, the laser light having a non-recording laser power smaller than a recording sensitivity of the inorganic resist layer, producing recording power control data indicating recording laser powers in accordance with the radius positions of the optical disk master-forming substrate by using the reflectances measured, forming an exposure pattern on the inorganic resist layer by applying the laser light to the optical disk master-forming substrate on the basis of the recording power control data while the recording power is varied in accordance with the radius positions, and developing the inorganic resist layer provided with the exposure pattern so as to prepare an uneven pattern.

Abstract: The present invention provides an optical information reproducing method of detecting a record mark formed in an optical information recording medium and generating a reproduced signal, comprising the steps of: detecting a mark length of each record mark on basis of a reproduced signal, and correcting the reproduced signal by a correction amount corresponding to the detected mark length, and an optical information reproducing apparatus for detecting a record mark formed in an optical information recording medium and generating a reproduced signal, comprising: a detection circuit for detecting a mark length of each record mark on basis of a reproduced signal, and a correction circuit for correcting the reproduced signal by a correction amount corresponding to the detected mark length.

Abstract: A disk drive is disclosed comprising a disk having a plurality of servo sectors defining a plurality of servo tracks that form a plurality of servo zones. The disk drive further comprises a head actuated radially over the disk for generating a read signal, and control circuitry operable to execute a seek operation. A fixed rate clock is generated, and a disk locked clock is generated and synchronized to the servo data rate of the servo zone the head is over. The disk locked clock is used to generate a servo timing window relative to a circumferential location of the head and the servo sectors. The control circuitry seeks the head from the first servo zone to the second servo zone, and switches to the fixed rate clock to generate the servo timing window while the head transitions from the first servo zone to the second servo zone.

Abstract: An optical pickup apparatus comprises a first light source for emitting a first light flux having first wavelength ?1 (430 nm>?1>380 nm), a second light source for emitting a second light flux having second wavelength ?2 (?2>?1), an objective optical system having phase structure thereon, and at least one moving optical element for guiding the light flux into the objective optical system, the moving optical element being moved in a direction parallel to an optical axis corresponding to the first light wavelength ?1 and the second light wavelength ?2, wherein the objective optical system has phase structure and satisfies M1=M2=0, where, M1 and M2 denote a first and second magnifications of the objective optical system for recording and/or reproducing the information on or from the first and second optical information media.

Abstract: An optical pickup apparatus for reproducing information from an optical information recording medium or for recording information onto an optical information recording medium, is provided with a first light source for emitting first light flux having a first wavelength; a second light source for emitting second light flux having a second wavelength, the first wavelength being different from the second wavelength; a converging optical system having an optical axis and a diffractive portion, and a photo detector; wherein in case that the first light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the first light flux is greater than that of any other ordered diffracted ray of the first light flux, and in case that the second light flux passes through the diffractive portion to generate at least one diffracted ray, an amount of n-th ordered diffracted ray of the second light flux is greater than that of any other ordered diffracted

Abstract: A track-jump control system and method are provided. The track-jump control system applied in an optical disc drive comprises a signal generator, a protection device, a velocity estimator, and a controller. The signal generator receives the signal from the PUH and generates a tracking signal and a position signal. The protection device receives the position signal and when the position signal represents the PUH pass a predetermined position of the optical disc, the protection device generates a protection signal. The velocity estimator estimates the velocity of the PUH according to the tracking signal, and then generates a velocity signal. The controller receives the velocity signal and the protection signal, protects the velocity signal according to the protection signal, and generates a control signal to control the track-jump according to the protected velocity signal.

Abstract: Data recovery information characterizes data recovery procedure (DRP) steps to be performed within a hard disk drive (HDD) in response to a miss. Particular data recovery information corresponds to a radial position of the actuator and, therefore, the position of the magnetic recording read/write head relative to the associated storage media at the location at which the miss occurred. The data recovery information is based on the physical shape of a write pole and on how the physical shape of the pole inherently affects operational data error associated with the head. Because of the foregoing characteristics of such data recovery information, a more efficient and performant data recovery procedure is performed based thereon.

Abstract: An optical recording medium wherein a laser beam at a wavelength ? is irradiated and recording and reproducing of information are performed by optical power modulation of binary or more, and when the refraction index of the first substrate being n1, the refraction index of the intermediate layer being n2, the groove depth, the groove width and the track pitch of the first information layer being d1, w1 and p1 respectively and the groove depth, the groove width and the track pitch of the second information layer being d2, w2 and p2 respectively, the following conditions are satisfied. 4?/16n1?d1?7?/16n1 ?/16n2?d2?3?/16n2 or 4?/16n2?d2?7?/16n2 0.2?w1/p1?0.55 0.2?w2/p2?0.

Abstract: An optical disk device includes an intermittent reproducing unit to perform an intermittent reproducing process to reproduce data recorded on an optical disk in a forward or reverse direction and at specific time intervals, each removing predetermined amount of data, an intermittent reproduction start instruction unit, upon receiving an instruction to start the intermittent reproducing process, to designate an intermittent reproduction start position and an intermittent reproducing direction, and to issue an instruction, and a storage unit to store the intermittent reproduction start position as information concerning a recording position for data skipped and unreproduced during a current intermittent reproducing process, when the instruction is issued.

Abstract: A write-once optical disc and a method and apparatus for recording management information of the write-once optical disc, are provided. The method includes sequentially recording data in the at least one recording-unit in the direction of increasing address; padding, with padding data, a remaining non-recorded part of a last recording-unit when terminating the sequential recording of the data; and recording padding identification information on the recording medium, the padding identification information identifying which part of the at least one recording-unit is padded.

Abstract: Plural grooves or lands formed in an information recording carrier include at least a wobbling region and data is recorded wobblingly in this wobbling region by phase shift modulation while recorded digitally with a single or multiple waves as a channel bit.

Abstract: A recording medium having a spare area for defect management and the management information of the spare area, a spare area allocation method, and a defect management method. When a primary spare area is allocated for slipping replacement and linear replacement upon initialization, and a remaining portion of the primary spare area after slipping replacement and allocated for linear replacement after initialization are insufficient, a supplementary spare area is allocated.

Abstract: A drive apparatus of the present invention includes: a recording/reproduction section, a drive control section and a memory circuit. The drive control section performs a process including: receiving a recording instruction specifying at least data to be recorded; storing the data to be recorded in the memory circuit; defining data from a start location of the data stored in the memory circuit to a location corresponding to a next writable address as a first data portion; defining data from the location corresponding to the next writable address to an end location of the data stored in the memory circuit as a second data portion; and controlling the recording/reproduction section to record the second data portion before recording the first data portion.

Abstract: A method to write information to a tape storage medium by disposing a tape storage medium in a tape drive apparatus comprising a write head. The method moves the tape storage medium in a first direction, writes data from a buffer to the tape storage medium, and thereby empties the buffer while the tape storage medium is moving in the first direction. The method determines, while the tape storage medium is moving in the first direction, whether to enable a backhitchless write wherein the tape storage medium is not stopped and moved in a second and opposition direction, prior to writing new data to the tape storage medium. By not stopping the movement of the tape storage medium, and by not moving the tape storage medium in a reverse direction to reposition the write head, the method eliminates the time overhead required to stop the tape and reposition the tape head. Applicants' method achieves this time efficiency without adverse impact to the nominal storage capacity of the tape information medium.

Abstract: A disk drive is disclosed comprising a head actuated over a disk, the disk including a plurality of servo sectors wherein each servo sector comprises at least one servo burst. A read signal emanating from the head is sampled while reading a servo burst in a servo sector to generate a plurality of sample values. A quality metric is generated in response to a plurality of sample values of a servo sub-burst representing part of the servo burst. When the quality metric does not exceed a threshold, the servo sub-burst sample values are excluded when generating a position error signal (PES) representing a position of the head over the disk. When the quality metric exceeds the threshold, the servo sub-burst sample values are included when generating the PES. The head is then positioned over the disk in response to the PES.

Abstract: An optical disk is equipped with a predetermined mark. A frequency generator outputs an FG pulse of frequency corresponding to the rotational speed of a spindle motor used for rotationally driving the optical disk. The edge of the FG pulse detected by an edge detection section is counted by an FG counter. An angle counter measures the duration of a time from appearance of an edge of the FG pulse until a point in time when the mark affixed to the optical disk 1 is detected. A count value of the FG counter, which has been acquired at the point in time when the mark is detected, and a count value of the angle counter are saved. In a case where a visible image is rendered, encoding of a visible image to be rendered is started when the count value of the FG counter and the count value of the angle counter have become equal to the respective saved values.

Abstract: In an optical pickup apparatus, a collimator lens is rockably supported by edges of two protruding portions formed on opposing sides of a groove of an optical base. The collimator lens is urged against the edges of the two protruding portions by a leaf spring. The position in vertical direction of one end of the leaf spring is adjusted by a position adjustor. In this manner, a tilt angle of the collimator lens is adjusted. Therefore, astigmatism of the light spot can precisely be compensated for irrespective of variations among apparatuses to achieve an excellent light spot.

Abstract: A method of recording information using a laser on a multilayer optical disk having a plurality of recording layers is provided. The plurality of recording layers include a first recording layer and a second recording layer adjacent the first recording layer. The first recording layer is provided with a first test writing area to be used for calibration of write power, and the second recording layer is provided with a second test writing area to be used for calibration of write power. The disk is arranged so that a first region of the first test writing area is superposed with a second region of the second test writing area when considered in the direction in which the laser is arranged to irradiate.