Vol. 5, Issue 1, Part B (2023)

Humans live in a 24-hour environment, in which light and darkness follow a diurnal pattern. In humans, the known effects of light on circadian rhythms and sleep are all, without exception, mediated by the retina. The retina is a fine layer of nerve tissue at the back of our eyes, containing specialized photoreceptors. Melanopsin RGCs are extremely sensitive to blue light and even exposure to light levels as low as the one from a smart-phone or light emitting e-readers are associated with disruptions of circadian rhythm. Melanopsin absorbs light in the short-wavelength range of the visible spectrum, with λmax at or near 480 nm. High-intensity blue light from any source is potentially hazardous to the eye. Industry sources of blue light are purposely filtered or shielded to protect users. However, it may be harmful to look directly at many high-power consumer LEDs simply because they are very bright. When Melanopsin is activated by the short wavelength component of light, it suppresses Melatonin synthesis. This action is controlled mainly by light could affect several functions including the regulation of intraocular pressure. Blue light or blue-violet light can be damaging to delicate retinal cells deep in the eye. No one knows exactly what causes dry macular degeneration. Research indicates that it may be a combination of family genes and environmental factors, including smoking, obesity and diet. The condition develops as the eye ages. Additionally, our studies have shown blue light is a risk factor for the onset of age-related macular degeneration, which is a progressive condition that can lead to vision loss over.