Zero reference generating method and apparatus for optical encoders
US4678908A · kind A · utility
49Cited by
5References
14Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Dec 5, 1984 |
| Grant date | Jul 7, 1987 |
| Priority date | — |
| Expiry date | Dec 5, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/308
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An encoder for providing positional information about a moveable member comprising code member means couplable to the moveable member for movement with the moveable member, reference means positioned to be stationary relative to the code member, an index sequence positioned on the code member, a mask sequence positioned on the reference member means, and means for detecting the degree of registration between the index sequence and the mask sequence, wherein the index sequence and the mask sequence include a plurality of building block patterns that are separated by predetermined spacings.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.