Have you tested Felix Gray glasses?



  • I realize that you feel the best path is a software solution, however many people wear blue light blocking glasses. Felix Gray is interesting because the glass itself isn't tinted. It's pretty clear. They claim to block 50% of blue light, while the more hard core orange glasses block to 99%. The obvious advantage is that they don't change the colors on the screen. Is this option worth a try or is 50% too low to make a significant difference?


  • f.lux team

    So, the thing to remember is that when we say "blue light" that isn't a standard measurement - meaning that many people use a slightly different definition. It's literally a spectrum, and to speak with certainty about how much is being blocked, we have to define the range first, of both the filter and of the light source.

    For f.lux, we focus mainly on the melanopic spectrum, which is the particular range of blue light that's been proven to suppress melatonin - that range falls between 400 and 580nm with a peak somewhere between 480 and 500nm. When you block that range, you are blocking most of the visible blue light, so you will definitely see a change in spectrum. For an example, the Uvex Amber glasses block about 42% of the melanopic light that come from an iPad. They are very visibly yellow. The Uvex SCT Orange glasses block about 95% of the melanopic light from that same iPad, and should have a better effect on sleep quality.

    We haven't measured the Felix Gray, but if you get a spectrum from the company we can help you figure out what it means. Many eyewear companies focus on HEV, high energy visible light, around 400-450nm. They talk a lot about what percentages they block without really defining what the range does. This almost surely helps with eyestrain, and probably won't do a lot to help sleep.

    Dimming your screens all way down at night will help a lot more than wearing clear glasses.

    You can try some of our models at https://fluxometer.com/rainbow/



  • Clear glasses are factually, obviously and logically not as effective as amber tinted. Higher end amber tinted glasses can cut a guaranteed 97%, 98%, 99% + cut reflection 100%. I use both macOS Night Shift / Flux + glasses after 5pm.