Integrated optical tracking system for magnetic media
AssigneeStorage Technology Corporation
InventorArchibald W. Smith
Life of this patent
Estimating the term…
Abstract
An improved servo system having an optical head array integrated into the magnetic head, and optical servo tracks incorporated on the magnetic side of a medium. The optical head array includes a light source array that individually illuminates the optical servo tracks through a beam splitter array and a lens array. Light beams incident on the optical servo tracks are individually reflected back through the lens array and beam splitter array to respective bi-cell photo detectors. The signals from the bi-cell photo detector are amplified by respective differential amplifiers to produce error signals indicative of the alignment of the magnetic head with the optical servo tracks. The error signals are combined by a circuit to produce a position error signal.
Claims15
An improved servo system having a combination head having a plurality of magnetic heads that read and write data in a magnetic side of a medium, the improvement comprises:
- a light source array attached to the plurality of magnetic heads, the light source array emitting an array of incident light beams;
- a plurality of optical servo tracks disposed on the magnetic side of the medium, the plurality of optical servo tracks reflecting the array of incident light beams to produce an array of reflected light beams;
- a bi-cell photo detector array attached to the plurality of magnetic heads, the bi-cell photo detector array converting the individual reflected light beams of the array of reflected light beams into an array of photo currents;
- a beam splitter array positioned between the plurality of optical servo tracks, the light source array and the bi-cell photo detector array, the beam splitter array being oriented to direct the array of incident light beams onto the plurality of optical servo tracks and to direct the array of reflected light beams onto the bi-cell photo detector array;
- a lens array positioned between the plurality of optical servo tracks and the beam splitter array to focus each individual incident light beam of the array of incident light beams onto a respective one optical servo track of the plurality of optical servo track, and focus each individual reflected light beam of the array of reflected light beams onto a respective one bi-cell photo detector of the bi-cell photo detector array;
- a differential amplifier array electrically connected to the bi-cell photo detector array, the differential amplifier array amplifying the array of photo currents to produce an array of error signals indicative of the alignment of the plurality of magnetic heads with the medium;
- and a circuit electrically connected to the differential amplifier array, the circuit combining the array of error signals to produce a position error signal.
Dependencies are inferred from the claim text.