Sayyiduna Anas bin Malik (may Allah be pleased with him) says that the Prophet (peace and blessings be upon him) appointed Sayyiduna Ibn Umm Maktum (may Allah be pleased with him) as his deputy; he would lead the people in prayer, and he was blind.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5117