Low-cost absolute linear optical encoder

US7180430B2 · kind B2 · utility

Assignee

• Avago Technologies ECBU IP (Singapore) Pte. Ltd. · SG

Inventors

• Kean Foong Ng · Bukit Mertajam, MY
• Hock Aun Tan · Jeniang, MY
• Moon Leong Low · Jeli, MY
• Yee Loong Chin · Batu Gajah, MY

Key dates

• Filing date: Nov 1, 2004
• Grant date: Feb 20, 2007
• Expiry date: Feb 3, 2025

Classification

• Technology area (CPC G): Physics
• CPC primary: G01D5/34715
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A Low-Cost Absolute Linear Optical Encoder (“LALOE”) for determining the absolute position of a read-head within the LALOE relative to a codestrip is disclosed. The LALOE may include an emitter module within the read-head, the emitter module having a plurality of light sources arranged in an light source pattern and a 90° Out-Of-Phase light source; and a detector module within the read-head, the detector module having a plurality of photo-detectors arranged in a photo-detector pattern corresponding to the light source pattern and a 90° Out-Of-Phase photo-detector corresponding to the 90° Out-Of-Phase light source.