Line-scan spectrum-encoded imaging by dual-comb interferometry.

Area of Science:

• Optics and Photonics
• Metrology
• 3-D Imaging

Background:

• Accurate 3-D profile measurement is crucial for various scientific and industrial applications.
• Traditional methods often face limitations in precision, speed, or simultaneous acquisition of multiple parameters.

Purpose of the Study:

• To introduce and validate a novel method for 3-D profile measurement using spectrum-encoded dual-comb interferometry.
• To achieve high-precision depth and absolute distance information with simultaneous reflectivity measurement.

Main Methods:

• Spectrum-encoded dual-comb interferometry combining spectral encoding, dual-comb interferometry, and optical referencing.
• Utilizing a reference arm for calibration and simultaneous data acquisition.
• Achieving free-running carrier-envelope offset frequencies for enhanced measurement capabilities.

Main Results:

• Obtained a 3-D profile of objects at a stand-off distance of 114 mm.
• Achieved a depth precision of 12 μm and a horizontal resolution of approximately 22 μm.
• Simultaneously measured absolute distance, reflectivity distribution, and depth information at a 5 kHz line-scan rate.

Conclusions:

• The spectrum-encoded dual-comb interferometry method is effective for high-precision 3-D profile measurement.
• The system demonstrates simultaneous acquisition of depth, distance, and reflectivity with excellent accuracy.
• This technique offers a promising solution for advanced metrology and imaging applications.