But advances in laser scanning gave her the breakthrough she needed and enabled her to match many pieces with their exact location in the caves.

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The laser scanning technology enabled us to investigate the natural environment in a completely new light by bringing the outcrop with its inaccessible cliffs, volcanic fissures and lava lakes into the computer where it could be analysed.

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This is a formidable undertaking: the process involves laser-scanning the caves, creating millimetre-perfect fibreglass replicas, and then painstakingly repainting each fresco.

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Dr Steven Willis, senior lecturer in archaeology at the University of Kent, said laser-scanning technology had been used to analyse the helmet and establish details of its manufacture, decoration and use.

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It works by scanning a laser beam across an object and manipulating the reflected light to produce an extremely narrow focal plane.

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The data can then be read simply by scanning the disc with another laser beam.

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This little miracle involves using tiny chip-mounted diffraction gratings and laser light passed over them via a scanning mirror.

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The laser moves back and forth across the width of the slide at 10 meters per second, scanning all 15 million cells in less than a minute.

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Using an instrument similar to the scanning bar-code guns at supermarket checkouts, this machine analyses black plastics with a laser.

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