LED lighting with higher CRI and spectral composition close to sunlight causes less eye damage
The study analysed the effects of LED lighting on the eye health of rats that were divided into four groups: a control group with natural light and three with LED lighting with different colour rendering quality (CRI: 10, 83 and 95). During the research, the scientists monitored changes in tear secretion, tear film breakup time, corneal fluorescein staining and structural changes in the retina. The results showed that the lower the CRI, the more severe the effects of exposure – most notably increased corneal damage, decreased photoreceptor numbers and thinning of the retina. In contrast, LED lighting with a higher CRI, close to the natural spectrum of sunlight, caused significantly less damage. This demonstrates that the spectral composition of light plays a key role in its safety for eye health.
Indicators of eye damage caused by LED lighting grew with increasing exposure time
Exposure to LED lighting can cause irreversible phototoxicity in the eye and associated corneal damage, destruction of tear film stability, inflammation and retinal degeneration. The researchers analysed changes in tear secretion, tear film breakup time and corneal fluorescein staining (CFS), which they found increased most with longer exposure to LED lighting with lower colour rendering index (CRI). This shows that full-spectrum sources with higher CRI are significantly better for the eyes of users compared to light sources with low CRI.
