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Half-Inch Monolithic Spatial Heterodyne Raman Spectrometer: A Study of Polarized Raman Spectra of Organic Liquids and
Evan M Kelly1, Miles J Egan1, Arelis Colόn2
1Hawaii Institute of Geophysics and Planetology, University of Hawaii at Manoa, Honolulu, Hawaii, USA.
Applied Spectroscopy
|June 10, 2024
Summary
This study introduces the compact spatial heterodyne Raman spectrometer (SHRSy) for analyzing polarized Raman spectra of organic liquids. The novel instrument offers simultaneous spectral capture, advancing material identification capabilities.
Area of Science:
- Spectroscopy
- Analytical Chemistry
- Optics
Background:
- Raman spectroscopy identifies materials via inelastic light scattering, with broad applications.
- Spatial Heterodyne Raman Spectrometers (SHRSy) are interferometric devices capturing entire spectra simultaneously.
- This work focuses on a miniaturized, two-grating monolithic SHRS (½-in. 2g-mSHRS).
Purpose of the Study:
- To test the performance of a compact ½-in. 2g-mSHRS.
- To investigate polarized Raman spectra of organic liquids using SHRS for the first time.
- To evaluate instrumental properties like resolution, spectral range, étendue, and field of view.
Main Methods:
- Excitation of organic liquids using a 532 nm Nd:YAG pulsed laser.
- Utilizing an excitation energy of 6.5 mJ/pulse and a 3 m distance.
- Employing an intensified charge-coupled device camera for spectral acquisition.
Main Results:
- Demonstrated the first use of SHRS for polarized Raman spectra of liquids.
- Characterized the performance of the compact ½-in. 2g-mSHRS.
- Compared instrumental properties against previous monolithic SHRS (mSHRS) designs.
Conclusions:
- The compact SHRSy is suitable for investigating polarized Raman spectra of liquids.
- The miniaturized instrument shows promise for portable material identification.
- Further characterization and comparison provide context for its performance.
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