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Implementation of a Reference Interferometer for Nanodetection
Published on: April 26, 2014
Diode-laser-based high-precision absolute distance interferometer of 20 m range
Florian Pollinger1, Karl Meiners-Hagen, Martin Wedde
1Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, D-38116 Braunschweig, Germany. Florian.Pollinger@ptb.de
Applied Optics
|November 12, 2009
Summary
This study introduces a hybrid absolute distance measurement technique combining multiple interferometry methods. The new approach achieves high accuracy, with measurement uncertainty under 12 micrometers at 20 meters.
Area of Science:
- Optics and Photonics
- Metrology
- Laser Interferometry
Background:
- Accurate absolute distance measurement is crucial in various scientific and industrial applications.
- Traditional interferometry methods face challenges in achieving high precision over long distances.
- Developing robust and accurate distance measurement techniques remains an active research area.
Purpose of the Study:
- To present a novel hybrid absolute distance measurement method.
- To combine frequency sweeping, variable synthetic, and two-wavelength fixed synthetic wavelength interferometry for enhanced performance.
- To experimentally validate the method's accuracy and uncertainty.
Main Methods:
- Implementation of a hybrid interferometry system using two external cavity diode lasers.
- Integration of frequency sweeping, variable synthetic wavelength, and two-wavelength fixed synthetic wavelength techniques.
- Experimental and theoretical analysis of measurement uncertainty.
Main Results:
- Successful realization of absolute distance measurements using the hybrid method.
- Experimental demonstration of measurement uncertainty below 12 micrometers at a distance of 20 meters.
- Theoretical validation supporting the experimental findings.
Conclusions:
- The proposed hybrid absolute distance measurement method offers high precision and accuracy.
- The combination of interferometric techniques effectively overcomes limitations of individual methods.
- This technique holds potential for advanced metrology applications requiring precise long-distance measurements.
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