I was recently watching Alec Guinness in "Smiley's People". The glasses are a big thing of Smiley's persona, and it looks fake especially in HD if they have flat glass instead of real 3-diopter lenses or whatever, because real glasses distort the actor's face behind them.
So I wondered if normal-sighted actors might wear, say -3 diopter contacts and then +3 diopter glasses to look credible but still be able to see.
>>> Do actors wear contact lenses to play someone in glasses?