Blue Light Spectroscopy from Electronic Visual Displays

Abstract

This work reports a collection of experiments having the purpose of understanding if a digital induced filtering process could reduce blue light subjection in humans. We used the software f.flux to digital filter different control color images displayed on various visual display devices. Wavelength spectra were measured with the help of a fiber optic spectrometer. A laptop LED display, CRT screen, a filament projector, LED-based projector, and a cellphone display were characterized. With the help of some standard RGB filters, also been optically characterized, the optical power from different color images displayed in two different displays (laptop and CRT) were measured. From these results, it was possible to estimate the presence and optical power of blue wavelengths in a red or green color image at a different level of digital filtering (color temperature). Our results indicate that the digital filtering technique is not enough to block blue light out completely overall when red or green color images were displayed in a laptop display. Interestingly the blue light optical power levels coming from red or green color images were of the same order of magnitude that the one has been found in experiments showing melatonin inhibition and a reduction up to 20% of melanopsin in rats. It is known that melanopsin and melatonin play an important role controlling circadian rhythms. Finally, a better strategy would be to use a CRT display along with the digital filter technique to avoid blue light power subjection coming from red or green color images.