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Fred Thomas Fred Thomas
Thomas Fred Charles, Wallentine Don W, Bero James, Wilson Scott: Acousto-optical intensity control of laser beam. Minnesota Mining And Manufacturing Company, KURTZ Richard E, December 23, 1993: WO/1993/025341

The intensity of a beam of light used to etch concentric servo tracks (12) on a magnetic medium is adjusted with an acousto-optical device to maintain the energy density delivered by the beam substantially constant while the optics (71) which generate the beam move radially of the disk (61).


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Fred Thomas Fred Thomas
Thomas Fred Charles, Wallentine Don W, Bero James, Wilson Scott: Steering laser beam while etching optical servo tracks for magnetic disks. Minnesota Mining And Manufacturing Company, KURTZ Richard E, December 23, 1993: WO/1993/026007

A beam of light used to etch servo tracks on a magnetic disk is steered with an acousto-optical device to maintain the beam in concentrical patterns while mechanically moving the optics which generate the beam of light continuously radially of the disk.