Method and device for redundant distance measurement and mismatch cancellation in phase-measurement systems

US7462808B2 · kind B2 · utility

Assignees

• MESA Imaging AG · CH
• IEE · LU

Inventors

• Felix Lustenberger · Marin-Epagnier, CH
• Thierry Oggier · Zürich, CH
• Guido Becker · Losheim am See, DE
• Laurent Lamesch · Reichlange, LU

Key dates

• Filing date: Aug 7, 2006
• Grant date: Dec 9, 2008
• Expiry date: Aug 7, 2026

Classification

• Technology area (CPC G): Physics
• CPC primary: G01S7/497
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The method serves for canceling errors caused by mismatch of different signal paths in a photodetector with a plurality (k) of storage elements for the photogenerated signals, as typically used in phase-measurement systems. The signal-capturing process is performed in at least two measurement cycles (j) . A first cycle (j=1) is executed with the conventional setup with no phase delay in the control signals. It is followed by further measurement cycles (j=2, 3, 4) which use control signals shifted by a constant phase shift (90°). Corresponding signals are read out through different signal paths. At the end, the signals corresponding to a certain phase (Φ) are added, thus canceling possible offset values.