With particular reference to myself

As a designer, Ralph Ball made modern classics like the Nomos table and the Aero lamp. As a sculptor, he makes mischief with them. Charles Darwent met him

When the owners of a London gallery offered to host a show of Ralph Ball's work last year, they found they were faced with a novel curatorial problem. The gallery was owned by Concord, a firm of commercial lighting designers, who use exhibitions to show off their products. The works Ball chose to show in the space were lighting systems of his own. "They seemed to be worried by the idea of having to spotlight spotlights," muses Ball, a tutor at the RCA. "An interesting conceptual question, don't you think?"

You can see how misunderstandings might arise. Ball's work, like his career, is hard to pin down. Ball is an industrial designer whose output includes the Nomos table (a cantilevered affair of steel and glass, designed for Norman Foster in the early 1980s and still de rigeur in certain sorts of Clerkenwell dining room) and the low-voltage Aero light of 1979 (those ubiquitous vertical wire tracks with spotlights suspended between them). His commercial designs teeter on the edge of sculpture. And his sculptures, contrariwise, are easily mistakable for commercial designs. "I quite like not fitting into a category," beams Ball, a man much given to conundrums, word games and the novels of Jorge Luis Borges. Spotlit spotlights would be right up his street.

The work in Ball's new show at London's Plateaux Gallery certainly suggests that spotlights gave him food for thought. "My students all kept going on about postmodernist issues like 'context'," says Ball, "and it seemed to me that a lot of it was bogus. So I decided to use this new work to carve out a visual language in which postmodernism took a look at modernism. That's why I called the new show Introspective Furniture."

Roughly translated, this means that Ball has decided to play games with various sacred cows of modernist design. Notably with that truncated- cone object we have come to think of as the Platonic lampshade.

In Golden Delicious, for example, he turns this lampshade upside down and fills it with light bulbs. "The idea behind the iconic lampshade is that it should contain light," says Ball. "If you invert it, though, it becomes literally a container, a bowl of light."

Photographs in the exhibition's accompanying literature come with po- faced exegeses of just what it is they represent. Next to A Spot Lighter than a Lighter Shade (a special prize for the person who can spot all the puns in that one), Ball has inscribed the modernist dicta: "Minimality, Transparency, Form follows function." Taking these axioms to their by no means logical conclusion, the Spot Lighter Than etc etc is a skeleton lampshade with no actual lampshade on it.

The more attentive among you may have spotted a problem in all this auto- criticising, though: namely, that Ball's own works have themselves become modernist icons. Ball, needless to say, has that one covered. The Task Lamp is his Aero lamp revisited, a work described by Ball as "a bit of postmodernist me". The Task Lamp solidifies the Aero's familiar tension wires into the uprights and rungs of a ladder, from which the iconic modern lampshade dangles as a window-cleaner's bucket. "Those kind of lights are called wall-washers, after all," chortles Ball. "Oh, and being in the modernist context, it also functions properly. You can hang the bucket from any of the rungs and it will still work." And as with the Aero lamp, so with the Nomos table. "Its look, the lunar landing feet and so on, has been incredibly influential," reasons Ball. "Everybody else has copied it, so I thought it was about time I did too."

Let it never be said that Ralph Ball can not take a joke. The T.4.4 - Ball's punning name for his re-invented Nomos - is so brazenly self-referential as to be self-mocking. (What Nomos-owners will make of this joke at the expense of their expensively purchased dining-tables is anybody's guess.) His award-winning invention turned both literally and metaphorically on its head, the Nomos's suction-pad feet become four china saucers on the ends of four waving antennae; the inverted lip-edged table-top becomes a tea tray on which the whole T.4.4 confection is served. Something of a bind come washing-up time? "Not at all," frowns Ralph Ball. "The saucers unscrew. It's modernist. Of course it functions."

'Introspective Furniture': Plateaux Gallery, SE21 (0171 357 6880), Thurs to 15 November.