Patent · US Expired

Measuring instrument

US4399612A · kind A · utility

2Cited by
2References
24Claims
0Family size

Inventor

Key dates

Filing dateJun 24, 1981
Grant dateAug 23, 1983
Priority date
Expiry dateJun 24, 2001

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D9/40
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A measuring instrument in the form of a plotter has a part-reflecting mirror device and a measuring mark or index which may be moved in X, Y and Z directions into coincidence with an image produced by the mirror device of an object to be plotted, contoured or measured, and means associated with the measuring mark or index for producing a plot, contour or measurement of the object, the mirror device comprising two parallel sheets of transparent material having the same optical properties and the same thickness, the image reflected by one or both of the adjacent surfaces being substantially stronger than any images reflected by the remaining surfaces of the sheets.

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