Double-grating Sagnac Fourier Transform Spectrometer

Category: Engineering and Physical Sciences

Reference Number: 00470

Description

Researchers in the University of Hawaii's Free-Electron Laser Group have developed a Fourier transform spectrometer based on a modified Sagnac interferometer. The instrument uses two gratings as dispersive elements to greatly improve the spectral resolution, and in-line optics to match the beam size in the interferometer to optimize the efficiency. A CCD or photodiode array is used as the detector and the fast Fourier transform of the fringe pattern is performed by a computer.

Applications

• Practical applications include remote sensing, process monitoring, and basic research.
• The fast response time of the detector also makes the spectrometer possible to perform real time spectral analysis.

Main Advantages

• The use of two gratings permits unprecedented spectral resolution by over an order of magnitude compared to the present state of the art.
• Since no mechanically moving part is used, this spectrometer is compact and easy to align.
• All other benefits of compact spatial Fourier transform spectrometers are retained, including compact size, rugged construction, single-shot recording with no moving parts, and quick response time.

Inventor(s)

Eric Szarmes, Associate Professor
Huan Ma, Research Assistant

Department of Physics & Astronomy

Contact Information

For more information, contact Andrea Yuen at ayuen@hawaii.edu