LEDs have the characteristics of color temperature and spectrum, and more and more people in medical, education and work environments are now using LED light sources for lighting applications to improve human life. Among them, some applications require high-precision spectrum, no change in optical power, and color does not change with time.
However, LEDs face two major challenges of temperature change and aging in meeting the requirements of human lighting applications. In response, researchers have developed a self-monitoring method to ensure the consistency of LED illumination.
It is reported that the study titled "Arbitrary Spectral Matching Using Multi-LED Lighting Systems" was published in the "SPIE Optical Engineering Journal" on March 29, 2019.
The paper shows that the authors adopted a two-pronged approach to simultaneously measure and autonomously adjust the spectral power distributions ("SPDs") of LED lighting systems.
The above figure is made by optimizing the weights of the 10 different channels of the LED light engine (dotted line). The four examples normalize the spectra and display them in arbitrary units.
In this method, fast computation and hyperspectral fidelity algorithms are used to determine the channel weight of the spectral power distribution. At the same time, the built-in microprocessor provides a closed-loop control system that controls and corrects the spectral output to compensate for variations in temperature.
Paper authors Aleix Llenas and Michael T. Eismann said they hope to develop a universal framework for multi-channel solid-state lighting (SSL) systems to ensure their research results are widely used in different lighting technologies.