Have you tried a cheap pair of readers in any of the supermarkets or the like to see if they make any difference?
I've got about 10 different pairs now, mainly from Good Lookers or London Mole. I love changing them on any day according to mood.
I think Mr L is quite resentful that he has to spend several hundred quid on a pair thanks to various prescriptions and coatings he has so only ever has two pairs at any given time when they are on special offer, whereas I have a range of styles and colours and I don't think I've paid more than £15 for any of them.