Encoder device for detecting movement
US7511260B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 2006 |
| Grant date | Mar 31, 2009 |
| Priority date | — |
| Expiry date | Jul 13, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/34715
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An encoder device includes first through fourth photodiodes each having a rhombus shape and a length of X1 in an X direction, the photodiodes being disposed adjacent to each other in the X direction such that a line passing through a pair of opposing vertices of the rhombus shape of each of the photodiodes is parallel to an X axis; a slit member that includes light transmitting sections and light shielding sections alternately arranged, and is movable in the X direction, each of the light transmitting and shielding sections having a length of 2×X1 in the X direction; and a logic circuit that generates first and second detection signals from output signals of the photodiodes that have received lights passing through the light transmitting sections, a phase of the second detection signal being shifted by a ¼ period of the first detection signal relative to the first detection signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.