It may not always be feasible to turn off sources of blue light after dark, but there are a variety of ways to reduce blue light exposure that may be interfering with your sleep. The most effective way to reduce exposure to blue light in the evening is to simply turn off the sources. This means dimming or reducing LED and fluorescent lighting in your home and turning off electronic devices after it gets dark outside.

On the other end of the visible light spectrum, blue light rays with the shortest wavelengths (and highest energy) are sometimes called blue-violet or violet light. This is why the invisible rays just beyond the visible light spectrum are called ultraviolet (UV) radiation.

Blue light from sunlight is very important in regulating circadian rhythm — our natural wakefulness and sleep cycle. Exposure to blue light from the sun during daytime hours helps maintain a healthy circadian rhythm. Blue light filters and protective eyewear

Animal studies and lab studies have raised questions about whether blue light could speed up the process of macular degeneration. Still, eye doctors and researchers do not think there is a verifiable link between using LED or blue-light-emitting devices and AMD. You may already be aware of software fixes for blue light, such as Apple’s Night Shift setting, which reduces levels of blue light, according to the time in your region, to reduce the intensity of the display: “Night Shift automatically adjusts the colours of your display to the warmer end of the spectrum – making the display easier on your eyes.” The result is that you lose the ability to see the center of your field of vision. You may still be able to see things on the periphery. But details and objects in the center of your sight lines may become blurry and, over time, more difficult to see.Too much exposure to ultraviolet light from the sunincreases the risks of eye diseases, including cataracts, growths on the eye and cancer. We know less about blue light. Its effects are still being researched. Although people often associate blue light with computers and phones, the largest source of blue light is sunlight. Other sources include fluorescent light, compact fluorescent light bulbs and LED light. Blue light exposure from screens is much less than the amount of exposure from the sun. It's also no more damaging than blue light from the sun, Dr. Khurana says. f.lux is a similar program available for Mac, PC, iOS and Android. The issue with both Night Shift and f.lux is that they give screens a reddish or orange tint towards the end of the day – which isn’t ideal for watching Netflix shows or enjoying pretty much anything in its original colors. Maytin EV, et al. (2018). Blue light versus red light for photodynamic therapy of basal cell carcinoma in patients with Gorlin syndrome: A bilaterally controlled comparison study.

A study by the US National Institutes of Health writes that "More than one-third of wearers found that a clear lens with a blue-filtering coating (BT lens, which all limit blue light up to 20%) provided better anti-glare performance and improved their vision for computer and mobile digital screens."Margrain TH, Boulton M, Marshall J, Sliney DH (September 2004). "Do blue light filters confer protection against age-related macular degeneration?". Prog Retin Eye Res. 23 (5): 523–31. doi: 10.1016/j.preteyeres.2004.05.001. PMID 15302349. S2CID 40276594.

Those structures don’t keep out blue light. And you’re exposed to a lot of it — the natural blue light from the sun far exceeds the amount from any one device. Position Statement on the Blue Light Hazard (April 23, 2019) | CIE". www.cie.co.at . Retrieved 2019-07-24.

Is blue light ruining my sleep?

Blue light does affect the body’s circadian rhythm, our natural wake and sleep cycle. During the day, blue light wakes us up and stimulates us. But too much blue light exposure late at night from your phone, tablet or computer can make it harder to get to sleep. Apple's and Microsoft's operating systems and even the preset settings of standalone computer monitors include options to reduce blue-light emissions by adjusting color temperature to a warmer gamut. [25] [26] However, these settings dramatically reduce the size of the color gamut of the display, as they essentially simulate tritan color blindness, thereby sacrificing the usability of the displays. The filters can be set on a schedule to activate only when the sun is down. Tsankov, Plamen Ts. (2020). "Lighting Technologies". In Pavlovic, Tomislav (ed.). The Sun and Photovoltaic Technologies. Cham, Switzerland: Springer Nature Switzerland. p.261. ISBN 978-3-030-22402-8 . Retrieved May 26, 2022.