Blue light filter software expert, Daniel Georgiev, is todays guest interview. Daniel shares some of the reasons why he feels being able to block blue light emitted from computer screens helps protect the health of our eyes. He helps to explain other issues that create eye strain like flicker rate, screen brightness and pulse-width modulation. We also go into understanding the benefits having software that automatically changes the colour of a screen according to the day night cycle where you are in the world. We then find out about how each different version of the Iris software works plus a bonus give away to listeners. Go to the show notes for episode 20 at https://www.biohackerslab.com/ep20-daniel-georgiev/ for more links & highlights.