Bono has revealed the reason he wears his distinctive sunglasses - it's because he suffers from the condition of glaucoma.
The U2 frontman, who appears on the Graham Norton Show tonight, was asked whether he ever removes his signature eyewear.
"This is a good place to explain to people that I've had glaucoma for the last 20 years," Bono explained. "I have good treatments and I am going to be fine."
He joked afterwards: "You're not going to get this out of your head now and you will be saying 'Ah, poor old blind Bono.''
The band appear tonight on the show alongside Robert Downey Jr, Robert Duvall and Stephen Fry.
The musician also addressed criticism received for automatically uploading U2’s latest album, Songs of Innocence. "We wanted to do something fresh but it seems some people don't believe in Father Christmas," he said. "All those people who were uninterested in U2 are now mad at U2. As far as we are concerned, it's an improvement."
Bono seems to be getting used to having to defend his decision to release the album in such an unconventional fashion."Oh for God's sakes" he told Jo Whiley. "Really and truly - we get people who might want to delete it but nobody has deleted more U2 songs in the last five years than U2!"
The frontman also had to respond recently when asked on Facebook why they had released the album in shuch a 'rude' manner. “Oops … I’m sorry about that," Bono explained. "I had this beautiful idea … might have gotten carried away with ourselves. Artists are prone to that thing. A drop of megalomania, a touch of generosity, a dash of self-promotion, and deep fear that these songs that we poured our life into over the last few years might not be heard. There’s a lot of noise out there. I guess, we got a little noisy ourselves to get through it.”
Bono revealed that apparently 38 million people have listened to the album.
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