Calibração espectral de um sensor de luz multicanal

Abstract

Measuring light is crucial in various fields of knowledge, from agriculture, where it influences plant growth, to engineering, which relies on precise measurements for the development of efficient lighting systems. This work presents a method to calibrate the AS7341 light sensor, considering the influence of diffusers. The importance of calibration is justified by the lack of detailed information in the literature about the process, especially regarding diffusers. The proposed method uses an integrating sphere as a reference and optimizes the calibration coefficients to minimize the error between the spectrum reconstructed by the sensor and the reference spectrum. Different objective functions and optimization algorithms are compared to find the best combination. The results demonstrate that the method is effective in calibrating both the sensor channels and the diffusers, improving the accuracy of light measurements, particularly for the EQM function and the lsqnonlin algorithm. However, limitations such as the incomplete calibration of some channels and the lack of data for validation under different lighting conditions are identified.