Question:
There is a woman in the state of Ihraam who is weak-sighted and cannot cover her face because she does not see very well. She also does not want to uncover her face. Can she wear a Niqaab?
Answer:
All perfect praise be to Allah, the Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His Slave and Messenger.
The Messenger of Allah said, “A woman in the state of Ihraam does not wear Niqaab or gloves.” [Al-Bukhari] But it is permissible for her to let her head-covering garment drape from her head down over her face when non-Mahram (i.e., marriageable) men pass by her.
If she covers her face with a Niqaab for an excuse such as weak-sightedness, then she is liable to a Fidyah (expiation or ransom) because of committing a violation of Ihraam. Allah The Almighty Says (what means): {And whoever among you is ill or has an ailment of the head [making shaving necessary must offer] a ransom of fasting [three days] or charity or sacrifice.} [Quran 2:196]
Thus, she has the option to do either of three things: fast for three days, or feed six needy people half a Saa’ (double handful) for each, or slaughter a sheep and distribute the meat to the poor people living in the Sacred Sanctuary.
Allah Knows best.