The Queen has had eye surgery to remove a cataract.
The 92-year-old monarch underwent the successful procedure in May.
In recent weeks, the Queen has been seen wearing sunglasses at a number of events including the Royal Windsor Horse Show and Buckingham Palace garden parties.
The Press Association learned from a source that the Queen was treated as a day patient at the private King Edward VII's hospital in London.
When approached, a Buckingham Palace spokesman said: "I can confirm that the Queen successfully underwent a short planned procedure to treat a cataract last month."
It was business as usual for the head of state, who did not cancel or postpone any engagements.
Cataracts are when the lens, a small transparent disc inside the eye, develops cloudy patches.
Over time these patches usually become bigger causing blurry, misty vision and eventually blindness, if left untreated.