Blue light spectrum
Although blue light is essential for regulating circadian rhythms, improving alertness, and supporting cognitive function, its widespread presence has raised worries about its possible effects on general well-being.
[2] It emits more blue light than traditional incandescent bulbs, potentially impacting the quality of sleep and eye health if used excessively at night.
[2][8] Blue light is emitted by digital screens such as computers, tablets, smartphones, and televisions, which can lead to extended exposure in modern lives.
Blue light exposure to the cornea increases the production of reactive oxygen species (ROS),[9] molecules in corneal epithelial cells.
[11] Prolonged exposure to blue light leads to an increased rate of tear evaporation, resulting in dryness of the cornea and the development of dry eye syndrome.
Cumulative exposure to blue light also induces an increase in the production of ROS, free radicals, in the lens epithelial cells (hLECs) mitochondria.
[17] The primary cause of blue light’s effects on the retina is the production of ROS that leads to oxidative stress,[5][16][18] meaning the imbalance between the generation of harmful reactive free radicals and the body’s ability to conduct detoxification.
Phototoxicity is caused by lipofuscin, which builds up inside RPE cells as a consequence of photoreceptor metabolism that is enhanced by exposure to blue light.
[3][9] Exposure to blue light during daylight hours suppresses the secretion of melatonin, a hormone critical for circadian rhythm regulation.
[8] Melatonin is synthesised by the pineal gland, located in the middle of the brain, in response to darkness, signalling the body’s transition to sleep.
[3][9] However, exposure to blue light at night disrupts the production and release of melatonin, leading to sleep disturbances.
[19] The amount of blue light received by ipRGCs regulates the circadian rhythm to control cycles of alertness[20] and sleepiness.
When light stimulates and activates the SCN,[21] the paraventricular nucleus (PVN) of the hypothalamus receives more signals from a neurotransmitter called GABA.
[22] Harmful impacts on the well-being of the eye after prolonged exposure to blue light, particularly from digital screens or fluorescent lamps, have been observed.
[3] When the eye is exposed to excessive levels of blue light from sources such as digital screens, a series of photochemical reactions within the retina can be stimulated.
The photochemical reactions cause the production of ROS,[3] inducing oxidative stress and damage cellular components in the eye such as ipRGCs.
[25] Growing evidence suggests that youth physical and mental functioning may be negatively impacted by insufficient sleep, both in terms of quantity and quality.
[28] The blue-light filtering glasses can lessen the signs of digital eye strain and prevent causing phototoxic retinal damage.
Generally, over the past five to ten years, digital screen use has increased substantially with the rise of smartphone, tablet, and computer usage.
Blue light exposure during daylight hours ensures that our biological needs are in balance and affects our bodies and minds in order to regulate human behavior and circadian rhythm.
Meetings, conferences, and tasks could be completed in person, placing a limit on how much time workers spent doing work on their computers or phones.
The study found that technology based solutions that induce eye resting reduces the prevalence of CVS in computer users.
Future research based on these findings should aim to explore technologies such as facial-recognition and eye-tracking software to create more personalized CVS interventions.
