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Time-domain surface profile imaging via a hyperspectral Fourier transform spectrometer
Julia Rentz Dupuis1, M Selim Unlü
1Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215, USA. jrentz@optra.com
Optics Letters
|June 17, 2008
Summary
This study introduces a novel white-light reflection spectroscopy method using a hyperspectral Fourier transform spectrometer (HS-FTS) for precise time-domain surface profiling. The technique accurately maps optical thickness variations across surfaces by analyzing spectral modulation frequencies.
Area of Science:
- Optical Physics
- Spectroscopy
- Surface Metrology
Background:
- Accurate surface profiling is crucial for optical component manufacturing and characterization.
- Existing methods may lack spatial resolution or require complex setups.
Purpose of the Study:
- To develop a non-contact, high-resolution method for time-domain surface profile measurements.
- To utilize white-light reflection spectroscopy with a hyperspectral Fourier transform spectrometer (HS-FTS) for optical thickness mapping.
Main Methods:
- Employing white-light reflection spectroscopy with an HS-FTS.
- Measuring spectral modulation frequencies in reflected light from multilayer optical surfaces.
- Analyzing temporal satellite positions in interferogram space, a direct consequence of the Fourier relationship.
Main Results:
- Demonstration of a technique to measure spatially resolved optical thickness.
- Successful reconstruction of surface optical thickness profiles using HS-FTS data.
- The method leverages the Fourier transform's inherent link between spectral modulation and spatial information.
Conclusions:
- The described HS-FTS method offers a robust approach for time-domain surface profile characterization.
- This technique provides accurate optical thickness mapping, beneficial for advanced optical systems.
- The method's reliance on spectral modulation analysis simplifies complex surface metrology.
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