WHEN I was a teenager I wore sunglasses to make me look cool and trendy; when I was in my twenties I wore them to alleviate the effects of bright sunlight on hangovers and to hide my dilated pupils. Now I wear them because they protect my eyes and help me to see better on sunny days.

Actually that’s a lie. Of course I still wear sunglasses as much for trivial, show-off fashion purposes as practical, eye-saving ones. But what’s true is that as you get older — unless you are a movie star or rock star — you need to become a bit more discreet about the way you wear them. In your teens it doesn’t matter how rubbish your shades look on you: what counts is how expensive and chic the brand is. Later, though, what matters far more is how well they suit your face. Which is why I have been a bit worried, of late, about my Oakleys.

There are lots of things I still love about my Oakleys: the fact that they can withstand nuclear blasts; that the lenses are so good they can see even better than my eyes; that they come in a bag made out of lens cloth; that they are prescription jobs and therefore even more impressively expensive than ordinary ones. But I can’t pretend that their insect-eye-shaped lenses are particularly flattering to my face. In fact they make me look like the offspring of a horse that has mated with a giant fly.

So the time has come for me to acquire another pair, and I know exactly which ones. They are a brand I’d barely heard of until this week, but which I now realise I must have because they are worn by pretty much every model, actor and rock star from Kate Moss to Leonardo DiCaprio to Bono: Oliver Peoples.

There are two main reasons why celebs are drawn to Oliver Peoples. First, they are extremely high quality: frames handmade from expensive materials like titanium, fantastically good lenses. Secondly, as Oliver Peoples’ founder Larry Leight (pronounced Light. He likes to wear black, which goes with his hair; he’s a surf nut) explained to me on a trip over from his home in Los Angeles, they can’t resist the brand’s anti-marketing marketing strategy. Whereas the name or symbol of most sunglasses manufacturers is stamped clearly on the frame, the Oliver Peoples one is discreet almost to the point of nonexistence. This enables those in the know to nod smugly as they check out one another’s OPs like pedigree dogs sniffing each other’s bottoms. Celebrities love this sort of thing. It makes them feel that they are being clever and original and outside-the-box.

Leight is responsible for a great many sunglasses trends of the past two decades, such as the current women’s one for sunglasses with ridiculously huge black or tortoiseshell plastic frames. When Kate Moss was snapped wearing a pair — they are called Vanadis — they sold out almost instantly, causing a frantic Posh Spice to ring up begging them to find her some. Much the same happened with the ones that Uma Thurman wore — a model called Vibe — in Kill Bill: Vol 2. Tragically for Thurman wannabes, when her stylists picked them out for the film they were the last pair. Oliver Peoples does similar ones, but not that exact model.

Oliver Peoples made its name by cashing in on the obsession with all things retro in the late Eighties. “The whole world was going for Art Deco and vintage and there was a big demand for original eyewear from the Twenties, Thirties, Forties and Fifties,” says Leight. “So, for $6,000 I bought up the estate of a deceased optical distributor (called, funnily enough, Oliver Peoples). It had everything: glasses with round John Lennonesque frames; rimless frames decorated with etchings and filigree.

“People were going crazy for them and the phones rang off the hook. And that’s when we started doing designs of our own. We brought back the clip-on. We started the fashion for vintage retro with small metal frames; for antique finishes in brass, bronze and pewter; for combination frames in metal and tortoiseshell . . .”

Besides designing his own collections twice a year, Leight collaborates on eyewear collections for Prada, Paul Smith, Vera Wang and Miu Miu.

I thought he would be a good person to tell me what I should be wearing now, so I tried on one or two items from his new collection and asked his advice. His personal favourites were a pair with heavy plastic frames à la Mafia don meets Aristotle Onassis; and some aviators with big lenses and green shading, à la Starsky and Hutch meets Seventies pimp. “That hardly helps me. They are completely different,” I said. But then I suppose a sunglasses designer doesn’ t want to point clients to just one style. He wants them to buy lots of different pairs and use them like a dressing-up box. Tonight, Matthew, I’m going to be Tom Cruise. And tomorrow, Brad Pitt.

There are some basic rules, though. If you have a round face, don’t wear round sunglasses; if you have a square face, don’t wear ones with hard angles; if you have a long face, don’t wear ones with droopy frames. Next comes balance. It’s not a good idea to wear frames that are wider than your forehead. You also need to be aware of symmetry and how well they work with your eyebrows. Probably best, says Leight, to see a professional optician, who will have the time and expertise to go through all the options and work out what suits you. He recommends Adam Simmonds in Camden, 020-7813 1234.

Oh, and apparently, unlike for women, there is no one style for men that’s in at the moment. Thick plastic frames are cool, so too are aviators with thin metal frames. Aviator variants, he suggests, are the safest bet because they are classic, functional and look good on almost everyone.

www.oliverpeoples.com

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