Afocal coupled etalons. DEM: a high-resolution doubleetalon modulator spectrometer

Area of Science:

• Optical Engineering
• Spectroscopy
• Instrument Design

Background:

• Fabry-Perot spectrometers are crucial for high-resolution spectroscopy.
• Single-etalon, single-aperture designs face limitations in luminosity and throughput.
• Coupled etalon systems offer potential for enhanced performance.

Purpose of the Study:

• Investigate the properties of a dual-etalon system coupled by an afocal system.
• Focus on the high-luminosity behavior of this coupled dual-etalon system.
• Analyze its performance as a high-luminosity, single-etalon, single-aperture Fabry-Perot spectrometer.

Main Methods:

• Theoretical investigation of a dual-etalon system.
• Analysis of the high-luminosity condition defined by etalon order relation n(01) = n(02)eta(-2).
• Examination of the role of the coupling constant eta and etalon gap nonlinearity.

Main Results:

• Achieved luminosity gains near 100 compared to single-etalon systems at high resolving powers.
• Demonstrated that gains are significant when the coupling constant eta is near unity.
• Identified the double-etalon modulator (DEM) as a compensated spectrometer.

Conclusions:

• The coupled dual-etalon system can significantly enhance spectrometer luminosity and throughput.
• The double-etalon modulator (DEM) exhibits compensated behavior, improving gain with resolution.
• Practical limitations like beam walk-off require consideration for real-world applications.