John Milton

His sight began to fail him at first upon his writing against Salmasius, and before it was full completed one eye absolutely failed. Upon the writing of the other books, after that, his other eye decayed. His eye-sight was decaying about 20 years before his death. His father read without spectacles at 84. His mother had very weak eyes, and used spectacles presently (very soon) after she was 30 years old.