Abstract:
In a method of writing clock data to a storage medium whilst the storage medium is rotating, a burst of clock data is read from a present track. A burst of clock data for a subsequent track on the storage medium is generated in accordance with the burst of clock data read from the present track and its phase adjusted. The phase adjusted burst of clock data is written to the subsequent track. The steps are repeated for plural bursts of clock data around a revolution of the storage medium thereby to write clock data to the subsequent track.
Abstract:
A first clock track is written to a data storage region of a storage medium at a first position between first and second boundaries. A first set of further clock tracks is written to other positions on the data storage region, these other positions lying between the first position and the first boundary. A second set of further clock tracks is written to other positions on the data storage region, these second other positions lying between the first position and the second boundary.
Abstract:
An off-axis optical pickup mechanism for dual-sided optical storage discs comprises an optical pickup unit (OPU) connected to an optical pipe. A baffle is provided which surrounds the OPU and a cover is provided which is placed on top of the baffle. To be able to controllably rotate the optical pipe, a first gear is attached to the pipe. The first gear is meshed with the second gear which is connected to the motor. The optical pipe comprises a top hollow tube having a top channel and a bottom tube having a bottom channel, and a main body having a main channel. Each channel terminates to a lens element. The optical pickup mechanism should be positioned in an optical storage drive such that an optical storage disc can be placed in between the two lens element of the optical pipe.
Abstract:
A servo sector allocation scheme for a disk based data storage system is disclosed that realizes an increased servo sampling rate without an associated increase in overhead. The scheme involves increasing the number of servo sectors on a subset (preferable one) of the disk surfaces in the disk drive while reducing the number of servo sectors on all remaining disk surfaces. A master servo feedback signal is then derived from the surface(s) with an increased number of servo sectors and provided to a master PES controller (44). A slave servo feedback signal is derived from the surface that is being accessed and is provided to a slave PES controller (46). The master PES control signal (Xm) is then combined with the slave PES control signal (Xs) to form a single position error signal (Xe) that is used to control the positioning of a transducer (58).
Abstract:
Curvilinear servo sector patterns are produced on a master media by determining a series of offsets between a radially aligned reference and the desired curvilinear servo sector and expressing each offset as a delay that can be expressed in settings for controlling a master writer. Incorporation of the delay into the master writer allows a curvilinear servo sector pattern to be produced using data mapping that is ordinarily used for the radially aligned servo sector pattern. Thus, curvilinear servo sector patterns with a desired resolution are produced without increasing computational overhead or memory requirements, or decreasing throughput. The delay can be converted into control settings such as sector delay, clock cycle delay and residual fractional delay settings that each represent a portion of the delay. In certain embodiments, a piece-wise linear approximation of the curvilinear shape can be implemented to reduce the amount of required control data, and a master writer controller that generates pulses for multiple lasers can be implemented.
Abstract:
A method for adjusting the frequency response of a servo loop (28) is provided that positions a servo head (46) at a nominal position over a medium and determines the frequency response (80) of the servo loop (46). A compensation gain (79) is determined at the nominal position such that when the compensation gain (79) is combined with the servo loop's frequency response (80), the compensation gain (79) causes the frequency response (80) to approach a desired frequency response. In addition, a servo loop and a disc drive with such compensation gain are provided.
Abstract:
A signal recording apparatus for a video instrument using a magnetic recording medium which is capable of more accurately computing the signal to be recorded on the tape by correcting the output signal when affixing "1" or "0" after computing the output signal to which the pilot tone is affixed. In addition, one line block is used on the assumption that "0" or "1" is always affixed to the code word.
Abstract:
A method and device for storing and accessing information on a flat storage medium (116) having X and Y axes. A read/write head (120a) is positioned adjacent to the medium and an X-axis motor (108-109) creates a reciprocating substantially linear motion between the head and the medium along the X-axis of the medium. A Y-axis motor (112) creates a linear motion between the head and the medium along the Y-axis of the medium. The head causes information to be stored or accessed on the medium as the head moves across the X-axis of the medium. The relative substantially linear motion of the head along the Y-axis moves the head from track to track along the medium. The relative motion between the head and the medium can be created by moving either the head or the medium.
Abstract:
A data recording medium and a data processor for effecting correct tracking. When a detector (31) runs immediately above a track (2) as shown in (x), the signal (d) outputted by the detector (31) corresponds to the signal on the track (2). When the detector moves up and reaches a position shown in (y), the signal of a track (3) mixes into the detector signal (d) and the phase of short-wavelength components advances. On the contrary, when the detector (31) moves down and reaches the position shown in (z), the signal of the track (1) mixes into the detector signal (d) and the phase of the short-wavelength components is retarded. Accordingly, the position of the detector is detected as a phase difference. Since the phase difference of the short-wavelength components can thus be detected, correct tracking can be effected by moving the head until the detected phase difference falls within a predetermined range. The head position can be measured extremely accurately by a single detector, and great effects are brought forth for the reduction of the size and the production cost of the apparatus. Therefore, the present invention is particularly suitable for large capacity data recording.