Another laser that came close to being practical enough to use was the Tactical High Energy Laser, also known as the Nautilus laser (pictured above), which was designed to shoot down incoming artillery rounds.

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It operates by focusing a laser pulse in the air to create a high energy plasma ball (up to several kilometers away) at a target.

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And as the decayed material has an extremely high water content Mr Hansen said that most of the laser's energy is absorbed by the infected tissue, which is then vaporised.

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This year's contests include the largest-ever plasma screen (150 inches), the largest Organic Light-Emitting Diode TV (a new bright and energy-efficient screen), the first functioning laser television and the first TVs that receive high-quality wireless streaming from a high-definition signal.

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