Were historical standards for who was considered "blind" generally lower than in the modern day?

I have sometimes gotten the impression that blind people are referenced noticeably more commonly in historical documents than you would expect to see them in the modern day. It recently occurred to me that when blindness is mentioned in historical documents the qualifying standards for what they are referring to might be different than we would understand them today. In a society before the invention of vision correcting glasses, or at least before they had widespread availability, were the standards for what qualified as "blind" lower to include some people who today would not qualify as legally blind but still require glasses to function in daily life? This seems like it might be common sense, but I'm curious if this is actually something any historians have ever written on.