Patent · US Expired

Self calibrating contour measuring system using fringe counting interferometers

US4457625A · kind A · utility

90Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 13, 1981
Grant dateJul 3, 1984
Priority date
Expiry dateJul 13, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B11/245
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A measuring arrangement is disclosed for measuring the contour of a two or three dimensional surface in which a redundant configuration of distance measuring systems is positioned above the surface being measured. Each distance measuring system monitors distance measurements to a point proximate the surface as the measuring point is moved across the surface. The distance measurements are taken from a sufficient number of points on the surface such that a sufficient quantity of data is obtained to define the system geometry and also to define the position of each measurement point. The data is transformed by recognized mathematical techniques into the coordinate positions of all of the measured points on the surface. In one embodiment for measuring the contour of a three dimensional surface, a tetrahedral arrangement of four distance measuring interferometers includes three interferometers positioned in a planar array above the measured surface and a fourth interferometer positioned at a central apex thereof. A retroreflector is placed adjacent to the measured surface to define the measuring point, and is selectively movable across the measured surface. A tetrahedral truss is positi…

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