What are some metaphors of seeing and blindness in Tartuffe?

In order to consider the metaphors of blindness and seeing in a meaningful context, it is important to first establish that the main storyline revolves around these very concepts. Orgon “blindly” believes everything that the supposedly “holy man” Tartuffe tells him, disbelieving the proof and evidence to the contrary his family tries to alert him to. In this sense, Orgon is “blind,” as Elmire tells him:

I can’t find words to cope with such a case;Your blindness makes me quite astounded at you.You are bewitched with him, to disbelieveThe things we tell you happened here to-day.

When Orgon finally discovers Tartuff’s deceit and fraud, he finally sees the truth. Early on in the play, truth is associated with seeing:

That is the usual strain of all your kind;They must have every one as blind as they.They call you atheist if you have good eyes;And if you don’t adore their vain grimaces,You’ve neither faith nor care for sacred things.

To not see the truth is to be blind; on the other hand, if one has good eyes—in other words, simply observes plainly what is in front of them (in this case, the fakery and deceit of Tartuffe)—then they are falsely branded an “atheist” by those who do not see the truth in front of them.
In the last act, Orgon finally sees Tartuffe's deceit with his own eyes, both literally and metaphorically, finally coming to see the truth. This metaphor is extended to the prince as well, who is also astute enough to see the truth behind Tartuffe's charade. The prince's ability to see past Tartuffe's tricks is once again described in terms of sight:

His eyes can read men’s inmost hearts, and allThe art of hypocrites cannot deceive him.His sharp discernment sees things clear and true.