Patent · US Expired

Measurement of articles

US4323850A · kind A · utility

9Cited by
2References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 15, 1979
Grant dateApr 6, 1982
Priority date
Expiry dateNov 15, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B7/28
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

In order to measure, for example, the radius of curvature of a soft contact lens, the lens is mounted in a bath of the electrolyte and supported at its periphery on a tubular support. A probe movable along an axis has two electrodes mounted on it and the resistance or impedance between those electrodes and the mount is monitored; when the difference in these resistances or impedances equals a predetermined value, the probe is taken as being a predetermined distance from the lens and the position of the probe relative to the mount is measured by a transducer arrangement. The output from the transducer is converted to digital form and used to address a read-only-memory in which are stored values correlating the position of the probe along the axis with the radius of curvature of the lens.

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