Scale structures and methods usable in an absolute position transducer
US6664535B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 16, 2002 |
| Grant date | Dec 16, 2003 |
| Priority date | — |
| Expiry date | Jul 16, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/34792
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An absolute position-sensing device is usable to measure the relative position of two elements. An absolute scale includes an integrated track extending along a measuring axis of the scale. The integrated track includes a plurality of periodic portions interleaved with a plurality of non-periodic portions. Each periodic portion includes a plurality of periodically-placed scale elements. Each non-periodic portion includes a plurality of code elements indicative of an absolute measurement value. The code elements may have a length that is narrower along the measuring axis than the length of the periodic scale elements. The offset of the periodic-placed elements relative to a readhead of the device is combined with the absolute measurement value to determine an absolute position.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.