What actual conclusive evidence is there of permanent eye damage from use of display devices? I've worked tens of thousands of hours over the course of 30 year

What actual conclusive evidence is there of permanent eye damage from use of display devices? I've worked tens of thousands of hours over the course of 30 years on everything from old, beat up, blurry television sets to crappy monochrome LCD and CRT displays to the latest and greatest of today, and have never once had eye problems beyond brief periods of eye strain on some devices when I went more than 10 hours at a stretch. That's on top of my childhood sitting close to the TV. I always wondered why it was bad to sit close to the TV, and yet OK to spend 8 hours less than 2 feet away from monitors based on the same CRT technology. Is there some secret, damaging radiation that only reaches a few feet from the television? And did we fail to fix it with the introduction of many new display technologies?