The next dimension

Holography, once a throw away visual gimmick, has become a fully-grown science with the potential for a wealth of design and test applications. Helen Beasley hears about the latest developments from one of the field’s leading experts

Walking into Martin Richardson’s holographic studio is like walking into a giant camera. A huge collimating lens adorns one wall, while another lens peers down from the ceiling. `I wanted to make the process as clear as possible for people as soon as they walk into the studio,’ Richardson says.

Richardson, who works through his company THIS Holograms, is one of only around five holographers in the world – a surprisingly small number, considering how widespread holograms now are. And his skills look set to be even more in demand as holography starts to find applications in engineering.

Richardson became interested in holography twenty years ago while studying photography at the Royal College of Art. `If I said to people then: “I make holograms”, they’d say: “What’s a hologram?” Now they’re taken for granted. They’re on adverts, toothpaste packaging, everywhere,’ he says.

Holograms have grown up. They are no longer quirky gimmicks, 3D images of inanimate objects that provide only momentary surprise. Holography can perform a range of functions within industry, such as detection of invisible faults in aero-engines, and new possibilities in design are being opened up by the ability to create holograms from computer images.

`This is a really exciting new development in holography,’ says Richardson. `We’re witnessing a revolution. We can now use computer-generated images and we’re exploring the possibility of using full colour for applications such as CAD.’

Holograms can be created from computer images such as CAD files by displaying the image on an LCD screen rather than a cathode ray tube, and recording it holographically. By rotating the image to create up to 180 different stills, a 3D image is built up. This type of hologram can be made as large as billboard size – an important consideration, bearing in mind that advertising and promotion are the most obvious commercial uses for holography.

At the Detroit Auto Show earlier this year, President Bill Clinton was amazed by the full-colour holographic image of a car displayed at Ford’s stand. It was created by Texas-based Zebra Imaging, a company Richardson often works with. Onlookers were able to `walk’ into the car and study its interior, while a current of air passed around it thanks to animation.

The system, which cost Ford $4m, contained 900,000 individual exposures – more data than the film Titanic – a fact that visibly impressed the President.

But possibilities for the use of holograms in industry do not end there. `One of the largest users of holographic film is Rolls-Royce,’ says Richardson. It uses a method of producing holograms called interferometry. This involves taking two holographic exposures of a rotating turbine a millisecond apart. When the images are processed, otherwise invisible cracks in the turbine, which could lead to a disastrous failure under the stresses of operation, appear as black fringes.

Holographic interferometry is also used to to detect invisible but potentially disastrous faults in aeroplane tyres, says Richardson.

`Holography also has uses in acoustics and radar,’ says Richardson, `because its principles are not necessarily restricted to light. It is fundamentally a way of making images using wave-front formation.’

The possibilities for his particular skill are constantly expanding. His next commission will be for Nasa, as part of the US-European Columbus space station project. He will be designing two holographic images. The first is a relatively simple, solid 3D image of the space station. But the second image has Richardson far more excited.

`It is going to be a computer-generated hologram that will include animation, working from a wire frame structure, so as one moves from left to right and views it, the wire frame becomes a solid structure, and then a totally realistic representation. So we’re going through the entire design concept within the space of four seconds.’