Laser Blinding

I was wondering how powerful a laser had to be to be able to blind an eye permanently?
Also how much would the pain be?

I'm /NOT/ thinking of blinding someone or myself, I'm just curious.

The amount of laser power that can damage your eyes is explained in the OSHA Technical Manual on laser hazards. The answer is very complex. A more detailed explanation is presented in an article on Laser Safety in Laser Focus World. Standards have been established by the American National Standards Institute (ANSI) and the Food & Drug Administration (FDA) for classifying lasers in incremental ranges of power output as it relates to safety.

https://www.osha.gov/dts/osta/otm/otm_iii/otm_iii_6.html#4

http://www.laserfocusworld.com/arti...ch-impacts-future-laser-safety-standards.html