User blog comment:Sprinklemist/I is Back!/@comment-1221823-20101017032718/@comment-1874924-20101018041634

The threshold for "legally blind" is vision that can't be corrected to better than 20/200. For example, Shane would be legally blind if his glasses or contacts still left him seeing only "fuzzy balls of color"; but in fact, he's not legally blind because his visual deficiency can be corrected with glasses or contacts. As for things like tunnel vision, I don't know what the standards are.