Look on the bright side: light show at the Hayward Gallery

An innovative exhibition at the Hayward Gallery shows how artificial-light sculptures and installations can create an intriguing interactive experience

“And God said: Let there be light and there was.” Modern artists have long since thrown over the idea of God, of course, So have they of the heavens being the source of all light. With the invention of electricity, the development of the fluorescent bulb and the deployment of LED illumination man effectively divorced himself from natural light. Artificial light became a medium in itself, a means of advertising and a way of making a man-made environment. No wonder that artists, alongside their commercial brethren, took it up with such enthusiasm to create installations and sculptures.

All of which makes it a refreshing theme for an exhibition, one which the Hayward Gallery takes up with great confidence, filling its cavernous concrete spaces with bright sculptures and darkened installations that intrigue, confuse and mostly uplift.

It's not a complete show by any means. For that you would need to go back to the Dadaists and Futurists of the Twenties and Thirties, when art ceased to be just about objects but whole spaces in which the onlooker engaged with the sounds and reflections cast by mobile sculptures. Nor does it include the light installations in specific landscapes and buildings by artists such as Bruce Munro who have done so much to brighten the built and rural environment.

Instead, the Hayward, sensibly enough given the confines of a gallery, concentrates firmly on artificial light works of the past 50 years, when artists began to look on the medium as a form in itself.

The most obvious way has been through making light sculptures in which the random illumination of hundreds of LED bulbs creates their own intricate patterns. The show starts off with a couple of theatrical examples in Leo Villareal's computer-driven cluster of LED-studded steel rods and the Welsh artist's, Cerith Wyn Evans's pillars of incandescent tubes. Designed essentially as public sculptures they work wonderfully well in the high halls of modern buildings. More involving is Jim Campbell's Exploded View (Commuters) (2011), an assembly of LED lights that flicker on and off in rhythms that induce the viewer to make for himself figures and shapes.

Light more than other medium can play tricks on the onlooker. But surprisingly few modern artists seem to go down this route, although it was for a time an immensely popular form of show in the 19 century. Instead, they are much more concerned to shift the viewer's perceptions by immersing him or her in a light installation. Donning plastic shoe covers you enter through darkened doors rooms in which light, static or changing, fills the space and takes over your own view.

It can sound pretentious and, indeed, for those with a taste for the pomposities of art-speak, there are more than a few examples here. Cerith Wyn Evans's installation has the splendiferous title S=U=P=E=R=S=T=R=U=C=T=U=R=E ('TRACE ME BACK TO SOME LOUD, SHALLOW, CHILL, UNDERLYING MOTIVE'S OVERSPILL…'), which either says it all or nothing at all, while Dan Flavin would have the light cast by his corner installation, untitled (to the “innovator” of Wheeling Peachblow) as providing “the source that particularised this space yet prevented you from getting at the space that was so particular.” To which the only response could be “well, I never.”

Conceptual art tends to encourage such flights of froth and light installations in particular seem to arouse something essentially intellectual in the artists' approaches. They use light not to illuminate but to surround. “Please allow 15 minutes viewing time to experience the work's full effect” instructs James Turrell in Wedgework V. You are supposed to grope your way into the darkness, take a seat and stare at his diagonal light shapes. God may be dead but the modern artist still seems keen to arouse religious devotion.

Fortunately, there are plenty of artists who want a more active response from you. Anthony McCall, in You and I, Horizontal uses the cinematic device of wipes, video and mist haze to produce a light beam in which you can dance, prance and enter as well as circumnavigate, an entrancing experience.

Some artists also use the medium to comment directly on the world about us. The Chilean Iván Navarro, creates a cubicle with mirrors and lights to enclose you in a prison of endless repetitions as a metaphor for life under the Chilean military dictatorship. Jenny Holzer is one of the few artists represented here who use the language of commercial signs to make political and personal statements. Her revolving Monument consists of words taken from documents about the war on terror that scroll, red on white, around a semicircular tower in tiers, endlessly repeating themselves. It's a powerful expression of the mindless arrogance with which the so-called “war” has been pursued.

Her work, which has involved displaying and projecting slogans, declarations and even poems in buildings across America, is a reminder of the much bigger canvas on which light artists can and do work. The Hayward Gallery's more concentrated show is great fun. But it is light for light's sake rather than as a medium for changing and refreshing our view of the world as it exists.

If you really want to see how the artists of the past have used light to do this you should hasten to Rotterdam, where the Boijmans Museum is in the last weeks of an exemplary exhibition on Van Eyck, the great revolutionary of late mediaeval painting and the founding figure in many ways of Renaissance and modern art. The Road to Van Eyck is formally about how the breakthroughs of this early-15th-century artist in oil was preceded by a solid tradition of realism in the decades before. But what it also proves is just how radical an innovator he was. Where his predecessors had used gold leaf to portray the glistening metal of plate and robe, Van Eyck uses light and its reflection to re-create even more realistically its appearance. Where those before had used light to give significance to figures, Van Eyck uses its glare and its shadow to give solidity to his shapes.

At a time when British museums and galleries seem to have decided that only art after 1600 or 1700 is worthy of exhibition, the Rotterdam show is something very special indeed. We are unlikely ever to see again such an assembly of panels and drawings normally too fragile to travel.

Light Show, Hayward Gallery, London SE1 (020 7960 4200) to 28 April