Near-zero beam drift laser tracking and measurement system with two-stage compression structures.

Area of Science:

• Optical Engineering
• Metrology

Background:

• Laser trackers are crucial for large-scale precision measurements.
• Beam drift in laser tracking systems limits coordinate accuracy.
• Existing methods struggle to sufficiently mitigate beam drift.

Purpose of the Study:

• To introduce a near-zero beam drift tracking technology using two-stage compression.
• To improve the coordinate accuracy of laser trackers.
• To enable high-precision geometric measurements of large-scale instruments.

Main Methods:

• Implementation of a Galileo telescope system with 21.43x magnification for initial beam drift compression.
• Utilizing a dual-frequency interferometer to compress beam drift.
• Employing an improved four degrees of freedom position-sensitive detector for further beam drift reduction.

Main Results:

• Azimuth and pitch beam drift compressed to 2.41 and 2.92 arc-seconds, achieving 95.0% and 91.9% compression rates.
• Peak-to-peak beam drift reduced to 0.9 arc-seconds (azimuth) and 2.1 arc-seconds (pitch).
• Standard deviation of azimuth and pitch drift within 0.15 and 0.43 arc-seconds, respectively.
• Simulated improvement in laser tracker coordinate accuracy by 6.85 parts per million.

Conclusions:

• The developed two-stage compression system effectively minimizes beam drift.
• This technology significantly enhances laser tracker coordinate accuracy.
• The system is suitable for large-scale precision instrument geometric measurement applications.