A common question I get from my patients is “should I be worried about blue light?” In recent years, with more adults and children spending more time on digital devices, people have started to wonder more about the harmful effects of blue light. Here are 5 essential things you need to know about blue light: 1. What is Blue Light? It’s helpful to understand what exactly blue light is. Blue light, also called High Energy Visible (HEV) light, is one part of the light spectrum.