KM Thats my point that I think people here are missing - I had that, and now after the vision therapy I never have that anymore. The phone I have from when i started therapy (iphone 7) was near unusable a year ago. I remember 2 years ago when testing it, 10 seconds just staring at the apple logo loading and I felt pinching headache for 2 hours after. Now I read news on it and play games. Same with the macbook, improving every day with occasional headache after few hours, slight next day when I overdo it the day before, or when I dont take the 20 sec break after evey 20 mins, which helps a lot too. Also when its the only bright item in my vision, so i take care to have other lights on or a bright place when I work on it. Still, old computer - no breaks needed, but the progress is still spectacular.
My specialist said that the theory that the LEDs are in case of heterophoria and bad eye position hitting night vision rods in the eyes, making it as painful as if someone turned on bright light in a dark room, quite possible. Night vision rods in eyes are at the periphery (peripheral vision), thats why sometimes stars in the night sky are more visible when you dont focus right on them. Heterophoria - the place where light falls is the periphery, and not the center, which is sharpest vision part of the retina. In case of LEDs, which are especially bright, if that light is hitting your night vision rods, the pain makes a lot of sense.