FAQ – Blue Light, Sleep & Eye Health
Welcome to Lucia Eyes Learn – your hub for understanding how artificial light impacts your sleep, eye health, and overall well-being. Explore our expert-backed insights and discover how blue light glasses can help you reclaim restful nights and protect your vision.
What is Blue Light?
Blue light is a high-energy, short-wavelength light (between 400–500 nm) emitted by the sun, LEDs, and digital screens. While it helps regulate our circadian rhythm during the day, overexposure, especially at night, can throw your internal clock off balance.
How Blue Light Affects Sleep
Blue light exposure after dark suppresses melatonin, your body's natural sleep hormone. This can delay sleep onset, reduce sleep quality, and contribute to long-term circadian disruption. Research shows that blocking blue light in the evening significantly improves sleep onset, duration, and quality.
Melatonin: The Sleep Hormone
Melatonin helps signal to your body that it’s time to sleep. Even short bursts of artificial light in the 455–480 nm range can halt melatonin production for hours. This is especially problematic when using screens, overhead lights, or LEDs before bed.
The Problem with Artificial Light at Night
Modern lighting—LEDs, fluorescent bulbs, and screens—emits significant amounts of blue and green light, which your brain perceives as daylight. This tricks your body into staying alert and awake when it should be winding down.
Effects of Blue Light on Eye Health
Prolonged exposure to blue light during the day can cause:
Blue light scatters more than other wavelengths, making it harder to focus. Over time, chronic exposure may even contribute to retinal stress and macular degeneration.
Daytime vs. Nighttime Blue Light Glasses
Daytime Blue Light Glasses (Light Grey Tint Lenses):
Nighttime Blue Light Glasses (Red Lenses):
7. Why Not All Blue Light Glasses Are Equal
Many glasses advertised as “blue blockers” only filter a small percentage of blue light—often under 20%, especially in the critical 455–470 nm range. True nighttime protection requires lenses that block the entire spectrum of melatonin-disrupting wavelengths (up to 550 nm). At Lucia Eyes, we only offer glasses that meet these standards.