Method and system for angle measurement

US7697127B2 · kind B2 · utility

Assignee

• Trimble Navigation Limited · US

Inventors

• Michael Vogel · Schleifreisen, DE
• Andreas Glimm · Weimar, DE

Key dates

• Filing date: Sep 18, 2008
• Grant date: Apr 13, 2010
• Expiry date: Sep 18, 2028

Classification

• Technology area (CPC G): Physics
• CPC primary: G01D5/3473
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An angle measurement device includes a light source configured to emit light along an optical path and a patterned member positioned along the optical path and configured to rotate about an axis of rotation. The patterned member includes a periodic optical variation. Light passing through the patterned member provides a spatially modulated optical waveform. The angle measurement device also includes an imaging device positioned along the optical path and including a plurality of photosensitive elements disposed in an array configuration. The imaging device is configured to receive the spatially modulated optical waveform and provide a signal associated with light intensity at each of the plurality of photosensitive elements. The angle measurement device further includes an angle determination unit coupled to the imaging device and configured to compute a rotation angle of the patterned member based on a reference waveform and the provided signal.