Dispersive element based on grating and tunable Fabry-Perot filter in miniature spectrometer

Area of Science:

• Spectroscopy
• Optical Engineering
• Miniature Spectrometer Design

Background:

• Miniaturization of spectrometers often leads to decreased spectral resolution.
• Integrating optical components is crucial for developing compact analytical instruments.

Purpose of the Study:

• To present a new design for an integrated tunable Fabry-Perot filter and etched grating (IGFP) for miniature spectrometers.
• To demonstrate the effectiveness of the IGFP in maintaining high spectral resolution during miniaturization.

Main Methods:

• The IGFP design combines predispersion from an etched grating with the filtering effect of a tunable Fabry-Perot filter.
• The grating provides spatial spectral separation, while the FP filter refines spectral resolution.
• Experimental validation used narrowband and broadband light sources for high-resolution and wavelength scanning demonstrations.

Main Results:

• The IGFP demonstrated high spectral resolution, achieving sub-nanometer results.
• Experimental results closely matched those from a commercial optical spectrum analyzer.
• The IGFP design effectively addresses the spectral resolution degradation issue in miniaturized spectrometers.

Conclusions:

• The integrated tunable Fabry-Perot filter and etched grating (IGFP) offers a viable solution for high-resolution miniature spectrometers.
• This design overcomes limitations associated with spectrometer miniaturization.
• The IGFP approach enables advanced spectral analysis in compact devices.