Blue-Light Levels Emitted from Portable Electronic Devices Compared to Sunlight

Abstract

Over recent years, a technological revolution has taken place in which conventional lighting has been replaced by light emitting diodes (LEDs). Some studies have shown the possibility that blue light from these artificial sources could have deleterious effects on the retina. Considering that people spend a non-negligible time in front of screens from computers and mobile phones, the eyes receive blue light of different intensities depending on the source. Nevertheless, any study about the visual and non-visual effects of blue light must consider precise measurements taken from actual artificial sources. For this reason, we have analyzed the spectral emission of 10 different electronic devices and weighted them according to the hazard caused by blue light to the eyes, comparing the results with solar radiation simulated with a radiative transfer model. The maximum spectral irradiance of the measured electronic devices at 10 cm from the detector was located between 440 nm and 460 nm. The irradiance for blue light hazard ranged from 0.008 to 0.230 Wm−2 depending on the particular characteristics of each electronic device. In contrast, the solar radiances in the same spectral range are larger both under clear and cloudy conditions.

The association between time spent on screens and reading with myopia, premyopia and ocular biometric and anthropometric measures in 6‐ to 7‐year‐old schoolchildren in Ireland

“…45 Hence, those in the higher screentime categories may be more susceptible to myopia development during the period of faster axial elongation around 8-11 years. Of further concern, digital devices emit high levels of narrow band shortwavelength light, 46 which results in instability in refraction trending to myopia. 47 In the present study, premyopia was strongly associated with parental myopia, whereas myopia was not.…”

A review of the current state of research on artificial blue light safety as it applies to digital devices

“…One study found that the blue light spectral irradiance from tablets and smartphones set at maximum brightness ranges from 0.08 to 0.38% of the ICNIRP blue light exposure limit. In comparison, on a sunny day in June, the blue light exposure from viewing the sky in the United Kingdom is approximately 10.4% of ICNIRP's blue light exposure limit [ 24 , 56 ]. Another study reported that the proportion of blue light emitted from LEDs is not different from that of fluorescent lamps after controlling for the colour correlated temperature, and concluded that LEDs present no special blue light hazard relative to other types of lamps [ 15 ].…”

The COVID-19 Pandemic’s Consequences on Medical Students’ Sleep Patterns and Technology Addiction

“…In addition to harming the retina through the eye's refractive medium, excessive blue light (especially at night, when melatonin production is at its peak) inhibits melatonin secretion in the pineal gland, increases corticosteroid production, and adversely affects sleep quality. Dry eyes can result from this increase in cortisol production, because it decreases parasympathetic nerve excitability and tear secretion [6]. Melatonin induces sleepiness by operating as the hormonal trigger for the body's temperature loss at night and the induction of sleep [7].…”