On Thursday Sophie visited the charity's flying eye hospital, a DC-10 plane that brings surgery to those living in poverty-stricken areas, where she watched a man receive cataract surgery and tried her hand at the operation using a simulator.
Sophie also met medical volunteers from around the world who are sharing their skills with local eye care workers in a bid to improve eye care in the local communities.
On Thursday evening the Countess of Wessex donned a silk patterned dress and black heels as she attended a reception at the ITC Kolkata Hotel.
The 48-year-old was seen laughing with Hunter Cherwek, the medical Director of Alcon and Rob Walters.
The following day Sophie met with the man whose cornea transplant operation she witnessed on the ORBIS flying hospital and spoke to him about his progress since the operation.
The mother-of-two met with students at Susrut Eye Foundation and Hospital who are training to perform sight saving operations.
In the afternoon Sophie is scheduled to give a speech at a medical training symposium.
Prince Edward's wife will then journey to Qatar to meet with the donors who are providing financial support to ORBIS in India and Bangladesh.