Patent · US Expired

Calibration disk having discrete bands of calibration bumps

US6164118A · kind A · utility

99Cited by
12References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1998
Grant dateDec 26, 2000
Priority date
Expiry dateSep 30, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B2005/0016
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A calibration disk for calibrating the fly height of a head, includes spaced circumferencial bands on the disk extending in a concentric fashion from adjacent an outer diameter of the disk to near an inner diameter of the disk. Each of the bands include radial and circumferencial spaced asperity emulating bumps having a population sufficient to produce a constant and continuous output signal from a glide head when the glide head flies lower than a maximum height of the bumps. The height of the bumps within individual bands are substantially uniform, and the average heights of the bumps in each band differ from each other. The configuration of the bumps on the calibration disk advantageously avoids errors caused by disk waviness, runout, and contamination. Further, using the differing heights of the bumps on the calibration disk, a glide head can be calibrated on the glide tester without using an independent fly height measurements for the glide head. Thus, errors in the fly height measurement and the delay in mounting each glide head to a fly height tester are avoided.

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