UC Davis

This dissertation contributes to the investigations of the organic and inorganic materials’ reactions to the light sources, describing the artificial light sources and some of the problems due to the absorption of this light in organic materials. Its main focus is on using the available technologies to obtain a spectrum that accomplishes an ideal Spectral Power Distribution (SPD) for special applications such as plant growth and art exhibits.The developed model uses a genetic algorithm approach to optimize the parameters that produce the desired SPD by combining artificial light sources. The model is versatile and can be used for different variables, such as the light intensities or even the spectrum of single light sources. The work considered emulating three different desired SPDs identified to contribute in the agricultural plant and in the art venues where preserving museum artifacts is crucial. The artificial light sources implemented were based on Light Emitting Diodes (LEDs) and Cathodoluminescence Phosphor Lamp (CL) and grouped into two, three, or four quasi- monochromatic light sources for the evaluation. This study implemented a vacuum testing system to obtain the SPD data for different CL phosphor materials and mixtures. The genetic algorithm model, the SPD pre-processing, and the analysis was carried out using MATLAB. The model used the R-Square function to evaluate how much the obtained spectrum fits the desired spectrum. The simulation results of the genetics algorithms model were implemented using LEDs The GA method was applied to different groups of Quasi-Monochromatic Light sources (QMLSs) and LEDs, showing promising results with the optimized parameters.