Optical rotary position encoder
US6399940B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 10, 1999 |
| Grant date | Jun 4, 2002 |
| Priority date | — |
| Expiry date | May 10, 2019 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01D5/34715
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The present invention recognizes that the limiting structures to size reduction for an optical encoder were the laser diode/photo diode package and the photodetector with amplifier package(s). The invention includes removing the discrete components from the laser diode cover package and mounting the much smaller discrete components on a base framework. The photodetector with amplifier package of the invention have an altered photodetector/amplifier geometry including shortening the leads between them. This resulted in significant size reduction of the encoder, a reduction in required gain and resulting increase in bandwidth. The entire base framework is temperature cooled by disposing two thermo-electric coolers between the base framework and an adjacent heat sink. Such positioning of the two coolers between the base framework and it's adjacent heat sink stabilizes both the laser diode's and the photo detector's outputs. In addition this novel design stabilizes the entire footprint/base of the encoder from thermal effects, whatever their origin.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.