Hewlett-packard Development Company, L.P.

Other

Darwin Mitchel Hanks

Andrew L Van Brocklin

Andrew Koll

Lawrence Nathaniel Taugher

Paul James McClellan

Greg J Lipinski

David Pettigrew

Mike Salko

Alexandra Delorme

Alexandre P V Delorme

A lens actuator is calibrated by inputting a signal to the actuator to cause the actuator to move a lens from a first location to a second location, sensing a focus error signal generated in response to the movement of the lens, determining a distance moved by the lens in going from the first location to the second location from a predetermined characteristic of the focus error signal, and determining a gain of the actuator from the input signal and the distance moved.

Actuator calibration using a focus error signal

An optical printhead for a medium including material that forms an optically visible spot in response to energy of a predetermined wavelength, the optical printhead includes a laser configured to impart energy of the predetermined wavelength to the material through a fixed-focus lens arrangement.

Optical printhead

In one embodiment, a disk labeling system is configured to use calibration indicia to produce calibration data. A disk is then marked using a laser in a first position. The laser is then deflected from the first position into a second position, by applying an input according to the calibration data. The disk is then marked using the laser in the second position.

Optical disk labeling system and method

A control circuit creates a self-sensing active-damping voice coil. The control circuit includes a current sensor coupled to a voice coil. A first filter is coupled to the current sensor to create an error voltage that is proportional to the integral of an external acceleration applied to the voice coil. A second filter with a lead-lag component is coupled to the error voltage to create a voltage applied to the voice coil that substantially cancels the external acceleration below a pole defined by a lead-lag component thereby damping the external accelerations.

Self-sensing active-damping voice coil

Various embodiments and methods relating to the writing of a label on a disc at the same time that data is written upon the disk are disclosed.

Label writing

Methods and apparatus are disclosed for playing content. In one embodiment, an identification key is generated. The identification key is encrypted and transmitted to a playback drive. Encrypted content containing a content identification key is received. If the content identification key matches the identification key that was generated, the content is decrypted and played.

Method and apparatus for playing content

A processor-readable medium comprises processor-executable instructions. The instructions are configured for scanning a reference pattern on a disc to determine a first radial position of the laser, wherein the reference pattern is located at a first nominal distance from a center of the disc and extends to a second nominal distance from the center of the disc, wherein the first and second nominal distances are accurate to within a nominal runout tolerance. The instructions are also configured for reading media ID data on the disc only when the radial position is greater than or equal to the first nominal distance plus the nominal runout tolerance and is less than or equal to the second nominal distance minus the nominal runout tolerance.

Optical disc and method of printing optical disc

An optical system configured for optical data processing is disclosed. In one example of the system, a photodetector array is configured to obtain an image of light modulated by reflection off a data track defined on optical media. In this example, the image contains at least one framing mark and at least one data region. A post-processor is configured to analyze the image and to recognize the framing mark and data within the data region.

Optical data processing using photo-detector array and framing marks on optical media

A series of signals is applied to a lens actuator of a disc media marking device to respectively position a lens at a series of distances from an optical disc. A mark is formed on the optical disc at each of the distances of the lens from the optical disc by passing a light beam through the lens and onto the optical disc. The darkest of the marks is determined. The signal applied to the actuator corresponding to the darkest mark is determined.

Focus offset calibration

Methods and apparatus are disclosed for a content encryption scheme using programmable hardware. In one embodiment, a content request is transmitted to a content provider. In response to the content request, a session key is received and programmable hardware is configured using the session key to produce a first configuration. An identification key is generated and the first configuration of the programmable hardware is used to encrypt the identification key. The encrypted identification key is transmitted to the content provider. Encrypted content containing the identification key is then received.

Content encryption using programmable hardware

A method for error detection and correction comprising performing a first modulation error scan of said modulation symbol, marking data that fails to comply with a predetermined criteria, demodulating said modulation symbols, computing a first error syndrome using said demodulated symbols, and correcting errors using said error syndrome computation.

Error detection and correction employing modulation symbols satisfying predetermined criteria

A method and apparatus for reading an index mark pattern. The pattern may be formed on an optical disc medium. The optical disc medium may include a set of data arranged in a data field, and an index mark pattern for identifying a relative location of the data field.

Method and apparatus for acquiring an index mark

An error correction circuit for determining an error in rotational speed of a recordable disk of a disk drive includes a sinusoidal error calculation portion adapted to generate a true oscillation error signal, and a summation portion adapted to combine the true oscillation error with a spindle error signal to generate a total error signal. The sinusoidal error calculation portion is adapted to generate a new true oscillation error based on the total error signal.

Recordable disk rotational speed error correction circuit

A method of one embodiment of the invention is disclosed that determines optical disc vertical displacement information at a number of positions on an optical disc. The method interpolates optical disc vertical displacement information at a number of other positions on the optical disc from the vertical displacement information determined.

Interpolation of optical disc vertical displacement information

A disc media marking systems and methods facilitate optical disc labeling through calibration of a fine actuator using a reference pattern.

Growing community of inventors

Fort Collins, CO, United States of America

Darwin Mitchel Hanks