Ian Gillan has just “30 per cent vision” left.
The Deep Purple frontman finds it “achingly tiresome” trying to work these days because he struggles so much when using his laptop.
He told Uncut magazine: “It’s one of those things. I’ve only got 30 per cent vision. That won’t get better.
“It makes life mysterious. The hardest thing is working on my laptop.
“I can’t see anything on the screen unless I use my peripheral vision – I pick up a line by looking at it sideways. But you find a way. You adapt.
“But it’s achingly tiresome. It takes a long time to do the work.”
Ian turned 80 earlier this year and while he insisted not much has changed as he’s got older, he’s grateful he still has his sense of humour.
He said: “It’s hilarious this growing old thing. It’s a laugh a minute.
“Well, sometimes yes and sometimes no.
“I walk down the road and hear something drop off – clang, there’s something else gone.
“Nothing’s changed really apart from I can’t pole vault any more.
“Other than that, things move a little more slowly. But nothing’s changed.
“If you’ve got a sense of humour, you can get by with most things.”
Ian suggested retirement “isn’t far off” because he doesn’t want to turn into an “embarrassment”.
He said: “I think if I lose my energy I’m going to stop. I don’t want to be an embarrassment to anyone.
“We’re not far off that. It creeps up on you – you don’t really notice.
“But then this isn’t like a normal job. It’s all in your mind.
“The writing certainly is, and the ability.
“And these guys who I work with just seem to keep improving. The hard thing is to keep them down.”