Low-Cost Spectrophotometers: A Comparative Evaluation of Open-Source Architectures

Alex M. Rivera-Rivera; Daniela Martinez-Ortiz; François Quitin; Denis Terwagne; Stamatios C. Nicolis; Ernesto Altshuler; Alexandre Campo

arXiv · 2610.09180

Low-Cost Spectrophotometers: A Comparative Evaluation of Open-Source Architectures

Alex M. Rivera-Rivera·Daniela Martinez-Ortiz·François Quitin·Denis Terwagne·Stamatios C. Nicolis·Ernesto Altshuler·Alexandre Campo

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Abstract

The rapid growth of low-cost and open-source spectrophotometers has created a need for systematic methodologies to evaluate and compare alternative instrument architectures. This study presents a comparative assessment of three representative open-source spectrophotometric platforms, encompassing discrete multispectral sensing and continuous-spectrum imaging approaches. Their performance was evaluated against a commercial Thermo Scientific Genesys 30 spectrophotometer in terms of spectral agreement, portability, implementation complexity, and cost. The results demonstrate that no single architecture is universally optimal; instead, each presents distinct trade-offs that determine its suitability for specific applications. Multispectral sensor-based systems offer compact, low-power solutions for field deployment, whereas imaging-based platforms provide spectral performance closer to laboratory-grade instrumentation. All hardware designs, firmware, and software developed in this work are released as open-source resources to support reproducibility and further development. The study highlights the importance of matching instrument architecture to application requirements and proposes a practical framework for the evaluation and selection of low-cost spectrophotometers, facilitating the adoption of open-source analytical tools for water quality monitoring and related applications.

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Alex M. Rivera-Rivera, Daniela Martinez-Ortiz, François Quitin, Denis Terwagne, Stamatios C. Nicolis, Ernesto Altshuler, Alexandre Campo. 2026-10-06. Low-Cost Spectrophotometers: A Comparative Evaluation of Open-Source Architectures. https://arxiv.org/abs/2610.09180

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