Fashions in spectacles change even more slowly than fashions in jeans, in my humble opinion.

I haven't made a special study of it but I'd estimate that if it takes five years for trousers legs to narrow and then flare again, it takes about a decade for the shape of glasses to go from those lozenge-shaped, rimless, Sven Goran-Eriksson-style psycho-dentist horrors to the massive Joe 90 jobs you see today on city hipsters and the occasional eccentric OAP.

At one extreme, then, you have sleek modernity (or what passes for it on the high street) and at the other, clunky retro styles. These recall, at best, Michael Caine in Funeral In Berlin, at worst Jim Callaghan in Funeral In Brighton (or the 1979 Labour Party Conference as it's more properly known).

So, given that the current trend in specs is from smallish steel and chrome frames towards huge plastic ones, it seems an odd time to launch a super-modern gizmo that just about suits the first but will look ridiculous on the second – especially as it's the second that most of said gizmo's early-adopters will be wearing when it hits the market in 2014.

Still, that's what Google co-founder Sergey Brin did at New York Fashion Week last Sunday when he joined designer Diane Von Furstenberg on the catwalk in a pair of rimless spectacles on to which was clamped the company's new eyewear technology, Project Glass. Or Google Specs, as the bins have been dubbed. Brin even managed to persuade Sex And The City's Sarah Jessica Parker to model a pair.

The gizmo allows information from your smartphone to be beamed directly onto a small screen in front of the eye. There's also a pair of microphones built into the glasses so you can make calls too, at least in theory.

Imagining how the technology might impact on the real world, I can see the dads in the playground no longer spending most of their time staring down at their phones but staring vacantly into the middle distance instead. Either way, they'll still miss their loved one's spectacular double pike climbing frame dismount – that's the technical term for a messy playground accident – because they're trying to check the football scores. Which would be a shame because they might need an eyewitness account when they try to sue their local council over the mishap.

Predictably, the fashion pack is terribly excited at the thought of this new form of eyewear. If there's one thing fashion loves, it's a novelty item. So expect to see Karl Lagerfeld – and maybe even his cat, Choupette – sporting a pair soon. n