Abstract: An optical mechanism includes an optical beam-generating mechanism and a light pipe. The optical-beam generating mechanism is to generate an optical beam. The light pipe is to guide the optical beam to an optically writable surface.

Abstract: A tuned circuit is used to detect wobble clock inversions. The tuned circuit reacts to a wobble inversion with a change in amplitude that may be detected by a threshold detector. A bandpass tuned circuit is used to detect wobble clock inversions. The output of the bandpass tuned circuit is input to a saturating high-gain amplifier such as a comparator. The output of the saturating high-gain amplifier reacts to wobble inversions with a half-cycle that has an increased duration as compared to half-cycles without wobble inversions.

Abstract: A embodiment of the invention provides a system wherein a user desires to concurrently process data to/from different storage media, the storage media being alternately available to the user, the system comprising a first buffer for accepting data from a selected first one of the storage media, a second buffer for accepting data destined to be recorded on a second one of the storage media, a control circuit for loading the first buffer from the first media faster than the data is being processed by the user, thereby generating periods of time where data is not being loaded into the first buffer, and the control circuit further operative for transferring data from the second buffer to the second media during the generated periods.

Abstract: One embodiment provides a method of providing a user with information quicker than could be achieved by obtaining the information from a storage source, the method comprising receiving a request from a user for stored data accessible by the user, the stored data maintained on one or more disks accessible one at a time and wherein the disks have a latency between the time of the request and the time the information is actually available, and obtaining a first portion of the requested data from a source other than where the requested data is stored, the amount of the first portion spanning the latency period.

Abstract: In an optical disc drive, the read channel electronics and the wobble channel electronics are combined into one common channel, for reduced cost. When the drive is reading, the common channel is used for primary data and a read clock. When the drive is writing, the common channel is used for wobble data and a write clock. Two example embodiments are provided. In each example, a single front end amplifier, without automatic gain control, is used. In each example, a single PLL and a single data detector are used.

Abstract: A tuned circuit is used to detect wobble clock inversions. The tuned circuit reacts to a wobble inversion with a change in amplitude that may be detected by a threshold detector. A bandpass tuned circuit is used to detect wobble clock inversions. The output of the bandpass tuned circuit is input to a saturating high-gain amplifier such as a comparator. The output of the saturating high-gain amplifier reacts to wobble inversions with a half-cycle that has an increased duration as compared to half-cycles without wobble inversions.

Abstract: An apparatus and method for flexibly and precisely varying temporal placement and duration of pulses, within a train of high speed, high power optical pulses. The invention includes optics adapted for focusing on a layer of an information storage media. An optical pulse generator is coupled with the layer through the optics for generating a train of optical pulses, wherein each pulse has a respective temporal placement within the train and has a respective pulse duration. The respective pulse duration of each pulse is controlled by an amount of an analog duration control voltage, in accordance with a WRITE STRATEGY, which is based on a physical property of the layer of the information storage media. Similarly the respective temporal placement of each pulse is controlled by an amount of an analog temporal placement control voltage, in accordance with the WRITE STRATEGY.

Abstract: In an optical disc drive, signals from two satellite spots are used to cancel DC offset from a tracking error signal, and for generating a quadrature signal for determining direction of radial movement. The two satellite spots generate signals that are out of phase with the main tracking error signal by about one-fourth period.

Abstract: A tuned circuit is used to detect wobble clock inversions. The tuned circuit reacts to a wobble inversion with a change in amplitude that may be detected by a threshold detector. A bandpass tuned circuit is used to detect wobble clock inversions. The output of the bandpass tuned circuit is input to a saturating high-gain amplifier such as a comparator. The output of the saturating high-gain amplifier reacts to wobble inversions with a half-cycle that has an increased duration as compared to half-cycles without wobble inversions.

Abstract: In an optical disc drive, an analog calibration signal is generated that combines timing reference information and data information. During reading, and during writing of amorphous areas, the drive modulates the normally constant current supplied to the laser diode. The laser intensity is modulated normally during writing of reflective areas. The relative magnitudes of the intensity modulations, as measured in the calibration signal, are used to adjust the timing of writing data relative to a reference signal. Calibration may be made during reading or writing, without interfering with reading or writing.

Abstract: In an optical disc drive, signals from two satellite spots are used to cancel DC offset from a tracking error signal, and for generating a quadrature signal for determining direction of radial movement. The two satellite spots generate signals that are out of phase with the main tracking error signal by about one-fourth period.

Abstract: A method for adjusting a compensator in a feedback control system for a coupled plant, derives a plurality of forward error values from position error signals that are sensed as outputs from the plant in response to a disturbance of the plant's operation. The position error signals are determined over plural, increasingly forward, time segments. A plurality of compensator output values are also determined over predetermined plural increasing forward, time segments. The derived forward error values are applied as inputs to the plant in a back propagation order, that order being in reverse time order to the time order in which the forward position error values were derived. Plural back propagation error values result in response to the back propagation application of the forward position error values. The back propagation error values are derived from within a portion of the compensator which has been configured as a Direct Form II filter function.

Abstract: A test system for a piezoelectric element per se or a piezoelectric element in a physical system, which is subject to forces which deform the piezoelectric element, couples an electrical pulse to the piezoelectric element sufficient to stress the element and induce mechanical ringing upon pulse removal. The ringing electrical signal developed by the piezoelectric element characterizes the functionality of the piezoelectric element. A response circuit which is responsive to the ringing electrical signal provides an electrical signal indicative of the functional condition of the piezoelectric element. The electrical signal is peak detected. The peak detected voltage is compared with a reference voltage to provide an indication of the functionality of the piezoelectric element.

Abstract: A disk recording and/or reproduction device subject to acceleration forces in which the transducer track following function is augmented by an acceleration responsive transducer positioning control. The acceleration response is calibrated as a function of the position error of the transducer with respect to the center of the track being followed.