Manufacturability-Based COTS Imaging Spectrometer Implementation by Sensitivity Minimization Design Procedure

In this study, we present an advanced implementation procedure for a commercial off-the-shelf (COTS) imaging spectrometer that significantly minimizes the sensitivity of its optical design to leverage the manufacturability afforded by computerized numerical control (CNC) machining precision of 0.1 mm. We employ Monte Carlo simulations in ray tracing software to analyze the sensitivity of each optical component across all degrees of freedom (DoF), based on machining tolerances. Key angle factors that most significantly impact performance in the off-axis design are identified and corrected. Through the proposed procedure, our simulations reveal a spot size variation in spectral axis 0.0155 µm along with the designed one of 8.8 µm, which is ideal for a spectral channel based on a sensor pixel size of 9 µm. The imaging spectrometer was then fabricated using CNC machining, and its spectral distribution was validated using a standard Mercury-Argon line emission light source, demonstrating a strong linear correlation. This approach highlights the potential for realizing complex off-axis optical systems with improved performance and precision.