GENEVA, SWITZERLAND - Luxury watch brand Vacheron Constantin said Wednesday it had turned to security features more commonly used in bank notes and passports in its fight against counterfeiting.

At the annual exhibition of luxury watch brands in Geneva, the brand said it called on banknote and Swiss passport printer Orell Fuessli as well as Roger Pfund, a Swiss designer who produced graphics for banknotes and designed the current Swiss passport, to develop the security features.

"These techniques are so complex and require machines that are so expensive that they guarantee against all attempts at counterfeiting," a spokesman told AFP.

First to benefit from this new technology is its new Quai de l'Ile line, which incorporates several security features, some of which are only visible under ultra-violet light used to detect counterfeit notes.

Laser engraving without inking, for example, is used for the words 'Swiss Made' and 'Automatique' on the dials.

Laser engraving with inking, on the other hand, is used for some of the numerals, the date and day of the week and 'Vacheron Constantin Geneve'.

Meanwhile, the surface of the dial is also covered with fine white gold in the so-called metallisation process.

Through the process, a micro-text is printed on the dial that can only be seen with a magnifying glass.

Meanwhile, a security film that is commonly used in banknotes is also involved.

One the dial side, the film features a pattern of concentric lines while on the movement side, it has a pattern of hundreds of Maltese crosses and concentric lines.

In all, it takes some 16 hours to put in the security features on each watch.

Vacheron Constantin produces about 20,000 pieces of watches a year.

In 2006, Switzerland's watch industry federation said about 40 million counterfeit Swiss watches are produced around the world annually, almost twice as much as the number of orignals produced in Switzerland. --AFP