Numerical Modeling and Spectral Balancing of an LED-Based Reflectance Spectrophotometer (360–760 nm)

Mikhail E. Parfyonov; Dmitry N. Artemyev

doi:10.18287/JBPE26.12.020311

Authors

Mikhail E. Parfyonov Samara National Research University, Russian Federation http://orcid.org/0009-0005-4470-3765 (unauthenticated)
Dmitry N. Artemyev Samara National Research University, Russian Federation

DOI:

https://doi.org/10.18287/JBPE26.12.020311

Keywords:

reflectance spectrophotometry, diffuse reflection, optical design, CCD detector, constrained optimization

Abstract

This study presents numerical modeling and constrained spectral balancing of a compact LED-based reflectance spectrophotometer operating in the 360–760 nm range. The detected spectral response was modeled as a weighted superposition of individual LED emission spectra explicitly multiplied by the wavelength-dependent detector quantum efficiency QE(λ). In the baseline configuration with unit weights, the detected spectrum exhibited strong modulation, characterized by a coefficient of variation CV of 41.5%, peak-to-peak deviation of 131%, and maximum-to-minimum ratio of 4.24. Spectral balancing was formulated as a constrained minimization of the normalized variance over a 0.5 nm wavelength grid using a differential evolution algorithm with bounded non-negative weights. The optimized configuration reduced CV to 8.36%, peak-to-peak deviation to 32.2%, and max/min ratio to 1.39, corresponding to an approximately 80% reduction in global spectral non-uniformity as quantified by variance-based metrics. The proposed approach provides a quantitative methodology for spectral equalization in multi-LED reflectance spectrophotometers.

Author Biographies

Mikhail E. Parfyonov, Samara National Research University, Russian Federation

PhD student, department of Laser and Biotechnical Systems
Dmitry N. Artemyev, Samara National Research University, Russian Federation

PhD, department of Laser and Biotechnical Systems

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