Bono has finally given a reason as to why he can nearly always be seen sporting sunglasses.
Bono has had glaucoma for the last 20 years.
The U2 frontman is often seen sporting a pair of sunglasses when he appears in front of photographers, but the 54-year-old singer says he does this in order to protect his sensitive eyes.
Speaking on last night's Graham Norton show, he said: "This is a good place to explain to people that I've had glaucoma for the last 20 years.
"I have good treatments and I'm going to be fine. You're not going to get this out of your head now. You're going to be saying, 'Ah, poor old Bono.'"
The condition is caused by a build up of pressure within the eye that if left untreated, can lead to blindness.
Bono - whose band U2 recently released their latest album 'Songs of Innocence' via iTunes - has previously revealed that his eyes are sensitive to light, but has never admitted to having glaucoma.
In an interview with Rolling Stone magazine in 2005, Bono said he wore sunglasses so frequently because his eyes were "very sensitive to light".
He added: "If somebody takes my photograph, I will see the flash for the rest of the day.
"My right eye swells up... It's part vanity, it's part privacy and part sensitivity."