Two-dimensional angle measurement with sub-arcsecond precision and MHz update rate using heterodyne interferometry...

Area of Science:

• Optics and Photonics
• Metrology
• Instrumentation

Background:

• Heterodyne interferometry offers high precision and speed for measurements.
• Accurate angle measurement is critical in various scientific and industrial applications.

Purpose of the Study:

• To develop a high-accuracy, high-speed two-dimensional angle measurement system.
• To leverage optical frequency comb technology for enhanced interferometric measurements.

Main Methods:

• Combined discrete longitudinal modes of an optical frequency comb with an acousto-optic modulator.
• Utilized a self-designed grating-corner-cube sensor for angle detection.
• Employed heterodyne interferometry principles for signal processing.

Main Results:

• Achieved sub-arcsecond accuracy (0.073 arcsec) at a 3 MHz update rate.
• Demonstrated comparison residuals within 0.063 arcsec over a 300 arcsec range against a piezo stage.
• Successfully distinguished and reconstructed dynamic sinusoidal motion of 0.05 arcsec at 40 Hz.

Conclusions:

• The developed system provides a powerful tool for high-precision, high-speed angle metrology.
• The integration of optical frequency combs enhances the capabilities of heterodyne interferometry.
• The system shows potential for applications requiring rapid and accurate angular position sensing.