Patent · US Active

Displacement detecting device and scale

US9689662B2 · kind B2 · utility

1Cited by
1References
11Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 2, 2013
Grant dateJun 27, 2017
Priority date—
Expiry dateApr 27, 2036

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D2205/90
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A scale has marks whose pitch interval changes along a measurement direction in a manner that can be approximated to a quadratic or higher-order polynomial. A comparing unit calculates a difference between first relative position information and second relative position information per unit displacement in a position where a first displacement detecting unit is arranged. Then, an absolute position computing unit computes an absolute position in the measurement direction with respect to the scale based on absolute position information and the relative position information of at least one of the first relative position information and the second relative position information, and outputs the absolute position.

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