One opticians, Asda Vision Centre, said 40 per cent of children who came to get their eyes tested said they did so because they wanted wizard glasses.
An Asda spokesman said: "Imagine our surprise when we discovered it was due to the fact kids wanted to look like Harry Potter. Anything that encourages children to have regular eye tests is great news."
Meanwhile one of the owls which keepers think was stolen from a wildlife park because of the demand for pets like Harry Potter's Hedwig, has been returned.
Gizmo was found a few miles away from the park on someone's roof, but there is still no sign of his mate, Marnie.