Stacked, Mutually Rotated Diffraction Gratings as Enablers of Portable Visible Spectrometry

Area of Science:

• Optics and Photonics
• Spectroscopy
• Imaging Technology

Background:

• Two-dimensional color CMOS cameras are widely available.
• These cameras offer potential for widespread spectrometry applications.
• Effective spectrometry requires maximizing pixel utilization and enabling point-of-use calibration.

Purpose of the Study:

• To explore the use of CMOS cameras for ubiquitous spectrometry.
• To present a method for generating wide dynamic range dispersed spectra.
• To establish the theoretical framework for spectral analysis using this technique.

Main Methods:

• Utilizing stacked, mutually rotated transmission diffraction gratings.
• Generating multi-order, wide dynamic range dispersed visible spectra.
• Deriving the theoretical basis for spectral dispersion, resolution, and normalization.

Main Results:

• Demonstrated a method for generating suitable spectra for absorption, reflection, and fluorescence spectrometry.
• Derived theoretical principles for spectral analysis.
• Reported initial characterization of the system.

Conclusions:

• Stacked diffraction gratings coupled with CMOS cameras offer a viable approach to ubiquitous spectrometry.
• The developed method supports various spectrometry techniques with wide dynamic range.
• Further characterization and application are warranted.