Abstract: Inspection apparatus for determining the profile of textured spots extending in a pattern along a surface of a magnetic disk includes an interferometer which illuminates first and second, adjacently disposed test spots on the surface. The disk and the interferometer are moved, relative to one another, so that one of the test spots traverses the textured spots in the pattern while the other test spot is moved along a flat portion of the disk surface. In one embodiment, the inspection apparatus is built into the device forming the textured spots, providing feedback controlling the texturing process.

Abstract: Crater shaped bumps are made on a calibration disk which can be used for calibrating a PZT slider, the PZT slider in turn being used for detecting predetermined asperities on a production run magnetic disk. The crater shaped bumps emulate predetermined asperities of production run magnetic disks and especially asperities which are undesirable and would cause the production run disk to be discarded after testing by the PZT slider. Crater shaped bumps which emulate undesirable asperities on current production runs of magnetic disks have a diameter in the range of 10 to 25 .mu.m and a peripheral ridge with a height h.sub.r above a nominal surface of the calibration disk in the range of 75 to 120 nm. Close tolerance crater shaped bumps with this configuration can be made by impinging two or more pulses of laser energy on the same location of a calibration disk. By increasing the number of pulses the height of the peripheral ridge progressively increases.

Abstract: A disk texturing tool is used, for example, to provide textured spots in an annular portion of both sides of a hardfile disk. Disks are moved into and out of the texturing process in cassettes, through two disk-handling stations. In each disk-handling station, a lifter raises each individual disk from the cassette. The individual disk is then transferred to a pick-and-place mechanism, which moves it to a spindle. The spindle spins and translates the disk, so that both sides of the disk are exposed to beams derived from a pulsed laser. The pick-and-place mechanism then returns the disk to the lifter, which lowers it into the cassette pocket from which it was taken. The pick-and-place mechanism simultaneously moves one disk from the lifter to the spindle and another from the spindle to the lifter. While disks are moved by the pick-and-place mechanism of one disk-handling station, a disk in the spindle of the other disk-handling station is exposed to the laser beams.