Patent · US Expired

Apparatus and method for testing the calibration of a hard disk substrate tester

US4702101A · kind A · utility

6Cited by
4References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 12, 1985
Grant dateOct 27, 1987
Priority date
Expiry dateAug 12, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B33/10
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An apparatus for testing the calibration of hard disk substrate tester includes a calibrating micrometer moving a known surface to at least two distances from a non-contact detector in the hard disk surface tester and a known distance from each other, and further includes a piezoelectric transducer mounted to the known surface moved by the calibrating micrometer, and an oscillator oscillating the surface at predetermined frequencies and amplitudes. A method for determining the status of calibration of the hard disk substrate tester places a known surface at least two distances from or positions in relation to a surface detector in the hard disk substrate tester, determining the distance between these positions, driving the known surface usually by generating an oscillation thereof by a piezoelectric transducer at one or at a set or plurality of predetermined monotone frequencies and amplitudes, and determining the calibration of the hard disk substrate tester by comparing its output with the corresponding predetermined frequency and amplitude of the driven surface.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.