A high bandwidth three-axis out-of-plane motion measurement system based on optical beam deflection

Area of Science:

• Metrology and Measurement Science
• Optical Engineering
• Dynamic Systems Analysis

Background:

• Accurate multi-axis motion measurement is critical for characterizing dynamic systems and controlling motion stages.
• Existing methods may have limitations in simultaneously measuring out-of-plane motion across different scales.

Purpose of the Study:

• To develop and validate an optical beam deflection-based system for simultaneous three-axis out-of-plane motion measurement.
• To propose novel calibration strategies for enhanced measurement sensitivity and accuracy.
• To demonstrate the system's capability across micro- and macro-scale targets and various motion types.

Main Methods:

• Development of an optical beam deflection measurement system.
• Implementation of novel calibration strategies for system sensitivity.
• Experimental realization, calibration, and application of the measurement system.
• Characterization of coupled linear and angular motion using a piezo-actuated stage.
• High-bandwidth measurement of transient motion in Radio Frequency Micro-Electro-Mechanical System (RF-MEMS) switches.
• Measurement of micro-cantilever beam deformation to demonstrate angular motion sensing.

Main Results:

• The measurement system successfully achieved simultaneous three-axis out-of-plane motion measurement.
• Experimental results for a piezo-actuated stage showed agreement with theoretical predictions.
• High-bandwidth capabilities were demonstrated by measuring transient motion with a 60 μs rise time.
• The system effectively measured out-of-plane angular motion, as shown by cantilever beam deformation analysis.

Conclusions:

• The developed optical beam deflection system provides a versatile solution for multi-axis out-of-plane motion measurement.
• The proposed calibration methods enhance system accuracy and sensitivity.
• The system is capable of characterizing complex dynamic motions in both micro- and macro-scale applications, including RF-MEMS devices.