Noise-equivalent change in radiance for misalignment noise in a double-sided interferogram

Area of Science:

• Optical Engineering
• Spectroscopy
• Interferometry

Background:

• Optical alignment servo systems are crucial for Michelson interferometers and Fourier-transform infrared spectrometers.
• Random misalignments introduce noise, impacting data quality during measurements.
• Predicting this noise is essential for accurate instrument design and operation.

Purpose of the Study:

• To derive a formula for quantifying noise-equivalent change in radiance caused by servo system misalignment.
• To validate the accuracy of the derived formula through simulations.

Main Methods:

• Development of a theoretical formula to calculate radiance noise from servo misalignment.
• Simulation of interferometer measurements with introduced misalignment noise.
• Comparison of formula predictions against simulated measurement errors.

Main Results:

• A formula was successfully derived to predict noise-equivalent radiance change.
• The formula's predictions closely matched the errors observed in simulated interferometer data.
• Demonstrated the formula's accuracy in quantifying misalignment noise effects.

Conclusions:

• The derived formula provides a reliable method for engineers to predict misalignment noise in optical servo systems.
• This tool aids in designing more robust interferometers and spectrometers with improved data integrity.
• Understanding and predicting misalignment noise is key to enhancing the performance of optical measurement instruments.