According to the tests, they are really effective to block blue-green light and the side part is really effective to block peripheral light too. Even when playing my Switch late (I know not a great idea), I feel the tiredness and the need to go to bed, as reading a book would do, something that never happened without the glass. So far so good. On the negative part, the extendable branches are not really well designed and when pulled to full length to fit my head, the glasses become not confortable. The feel and looks made them more like a working tool than glasses you would wear for a couple of hours. Also, as a Canadian, the shipping was almost as expensive as the glasses and from my experience on the website, you learn about it once you've hit the payment button. For a 143$CAD, it's a steep price for what it is. But effective.