Abstract: A multi-zone calibration system is disclosed. The multi-zone calibration system calibrates the operating parameters of an optical disk drive over a plurality of zones over an optical media. The optical media, in addition, can have writeable and premastered portions. The operating parameters can be calibrated for each of the media types in each of the zones. Additionally, the operating parameters can be calibrated for each type of operation (e.g., read or write) in each zone.

Abstract: This disclosure describes an apparatus and method for measuring analytes in exhaled air. The device contains an inlet through which exhaled air is received. A tube, having a number of different paths running throughout the device, is coupled to the inlet which enables the exhaled air to be re-circulated through the device. At least one portion of the tube is configured in a non-linear fashion. This particular portion of the tube may be used to temporarily store a sample of the exhaled air. The device also contains a converter configured to partially convert an analyte in the exhaled breath from a first state to a second state as the exhaled air is being re-circulated. An analyte sensor is also included to measure the levels of the converted analyte in the exhaled breath.

Abstract: A servo system with in an optical disk drive with an inverse non-linearity compensation is disclosed. An error signal calculated from signals received from an optical pick-up unit can be offset by an offset value and amplified by a gain in the early stages of a calculation of a control signal for controlling a position of the optical pick-up unit. The non-linearity compensation adjusts the gain based on the offset value so that the response of the servo system to changes in the error signal is substantially linear. The error signal can be the tracking error signal in a tracking servo system and can be the focus error signal in a focus servo system.

Abstract: A focus servo system with a focus close algorithm is disclosed. The focus close algorithm provides a bias control effort to the focus servo system when focus is closed. A method of closing focus includes positioning an optical pick-up unit at a first position away from an optical medium, moving the optical pick-up unit towards a second position by altering a focus control effort, monitoring a sum signal obtained from signals received from the optical pick-up unit, and setting the bias control effort to the focus control effort when a closure criteria is satisfied. In some embodiments, the closure criteria includes that a sum signal exceeds a threshold value. In some embodiments, the closure criteria includes that a focus error signal is below a FES threshold.

Abstract: An off-format condition in a digital tracking servo is presented. An off-format condition can be detected by low pass filtering a tracking control signal, detecting a DC level over a threshold level, and indicating the off-format condition if the DC level is above the threshold level for a maximum number of cycles.

Abstract: A servo system with a multi-track seek algorithm with an acceleration clamp is presented. The multi-track seek algorithm detects zero crossings in a tracking error signal, counts the number of zero crossings to form a count, and calculates a reference velocity from the count. The algorithm also determines a time period between successive zero crossings, calculates a velocity from the time period, calculates a difference signal between the reference velocity and the velocity, and adjusts the control signal so that the velocity follows the reference velocity. The reference velocity can follow a velocity profile with acceleration portions, coasting portions, and deceleration portions which move an optical pick-up unit from a starting position to a target position. The acceleration of an optical pick-up unit is clamped during the multi-track seek operation.

Abstract: A system which calibrates notch filters in a digital servo system is presented. A notch filter can be calibrated by obtaining a frequency response curve of the digital servo system in a range of frequencies, searching the frequency response curve for at least one peak frequency, and adjusting parameters of the notch filter to filter out signals at the at least one peak frequency. The digital servo system, for example, can be a tracking servo system or a focus servo system of an optical disk drive.

Abstract: A calibration of a focus error signal gain in a focus servo system of an optical disk drive is presented. The focus error signal gain can be calibrated by oscillating an optical pick-up unit in a focus direction through a focus point and determining a focus sum threshold. The optical pick-up unit can then be oscillated around a focus control effort that results in a sum signal equal to the focus sum threshold and the peak-to-peak value of a focus error signal can be measured. The focus error signal gain can be determined from the peak-to-peak value of the focus error signal.

Abstract: A tracking and servo system with a one-track jump is disclosed. The one track jump algorithm holds a control signal from the tracking servo system. The one track jump algorithm adds an acceleration control signal to the held control signal for a first period of time, delays for a second period of time, and adds a deceleration control signal to the held control signal for a third period of time. The algorithm then frees the control signal to close tracking on a new track separated by one track from the starting track.

Abstract: A method of storing calibrated optical parameters is presented. In some embodiments, calibrated optical parameters are stored in place of stored parameters. In some embodiments, averages between the calibrated operating parameters and stored optical parameters are stored. In other embodiments, the stored optical parameters are allowed to vary only by a maximum amount. In some embodiments, if the calibrated parameters vary by more than threshold values, then the calibrated parameters are not stored.

Abstract: A write abort algorithm of a tracking and focus servo system that can abort a write operation on an optical disk drive is presented. The write abort algorithm monitors at least one of a tracking error signal or a focus error signal and indicates a write abort status when the tracking error signal or the focus error signal indicates a threshold value. In some embodiments, the write abort algorithms suspends indication of the write abort status in the presence of a defect, suspension of the write abort status occurs more than a predetermined number of times.

Abstract: A disc drive includes a tracking actuator, and determines when the tracking actuator is positioned off a formatted portion of optical media in the disc drive. The optical media includes a pitted premastered area that cannot be overwritten and a grooved user-writeable area that can be overwritten. Tracking control effort is monitored to determine when the tracking actuator is in the off-format condition and whether tracking good or tracking bad is detected within a predetermined time period. An absolute value of the tracking control effort is generated and the absolute value of the tracking control effort is filtered. An off-format condition is indicated if the filtered value of the tracking control effort is not within a predetermined threshold value.

Abstract: A focus error signal offset calibration is presented. The focus error signal offset can be calibrated by varying the focus error signal offset to optimize an operating characteristic of the optical disk drive. In some embodiments, the operating characteristic can be a servo function. In some embodiments, the operating characteristics can be a read function.

Abstract: A control system for controlling tracking and seeking in an optical disc drive for optical media with a pitted premastered area that cannot be overwritten and a grooved user-writeable area that can be overwritten. The control system determines whether an optical pickup unit is over the premastered or the writeable areas of the optical media by measuring peak to peak amplitude of a tracking error signal. Gains and calibration values are selected based on whether an optical pickup unit is over the premastered or the writeable areas of the optical media. Reading from and writing to the optical media is disabled while jumping tracks. Control of jumping tracks on the optical media includes controlling: jumping a single track on the optical media; jumping a specified number of tracks every specified number of revolutions of the optical media; auto jumpbacks, and jumping in forward or reverse directions.

Abstract: A system for controlling focus in an optical disc drive for optical media with a premastered area that cannot be overwritten and a user-writeable area that can be overwritten includes instructions for turning focus on and off; and for acquiring focus on the optical media in response to a command to acquire focus. The actuator arm is moved according to a sinusoidal ramp function to prevent exciting resonances in the actuator arm. The amount of push-away force used while moving the actuator arm can be adjusted to avoid overshoot. The integrity of a focus error signal is determined and an attempt to re-acquire focus is made if the focus error signal indicates a bad focus status.

Abstract: A system, method, and apparatus for coordinating tasks in a control system for an optical disc drive for optical media with a pitted premastered area that cannot be overwritten and a grooved user-writeable area that can be overwritten. The optical disc drive includes a first processor operable to communicate with a second processor, wherein the first processor includes instructions for performing non-time-critical tasks, and the second processor includes instructions for performing time-critical tasks, such as reading from and writing to optical media in the disc drive. The first processor monitors the status of the time critical tasks in the second processor and transmits commands to perform operations in the second processor. The first processor also controls power mode, manages recovery from errors, controls focus, tracking/seeking, spin, physical sector address (PSA), a laser, adjusts gains, and monitor cartridge load/eject.

Abstract: A system with a plurality of servo algorithms executing on a digital signal processor is presented. The digital signal processor receives a sensor interrupt, indicating availability of digitized data from optical sensors, and decides which of a plurality of servo algorithms to service in response to the interrupt. In some embodiments, the plurality of servo algorithms includes a tracking servo algorithm. In some embodiments, the plurality of servo algorithms includes a focus servo algorithm. In some embodiments, multi-track seek operations or one-track jump operations can also be serviced during the interrupt period.

Abstract: A calibration method for an optical disk drive is presented. The operating parameters of an optical disk drive are initially calibrated when the disk drive is produced or during a repair step. The disk drive is then field calibrated during normal operation. Operating parameters can be field calibrated during power up. Further, operating parameters can be field calibrated when a new optical media is inserted into the optical disk drive. Additionally, operating parameters can be field calibrated during error recovery.

Abstract: A digital servo system with a biased feed-forward control is disclosed. The biased feed-forward control determines the low frequency component of a control signal from the digital servo system. The low frequency component can then be added to a future control signal to form an adjusted control signal. In some embodiments, the low frequency component is then removed from the future control signals. In some embodiments, a bias signal is incremented or decremented in response to the low frequency component, the bias signal being added to future control signals.

Abstract: A defect detector in an optical disk drive is presented. The defect detector indicates a defect by monitoring a sum signal. The sum signal is calculated from optical signals from detectors in an optical pick-up unit of the optical disk drive. A defect can be indicated when a filtered sum signal, the filtered sum signal being the sum signal filtered with a high pass filter, is above a threshold value. In some embodiments, the defect detector can recognize changes in laser power or transitions between media types and not indicate defects during those occurrences.