This ESA test bench is usually shrouded in darkness, except for the laser beam being projected across it.
Human eyes are not normally supposed to witness the laser being fired – for this photo, it was fired at the lowest possible energy level, while the camera was switched to its highest light-sensitive settings for an exposure time of half a second.
Lasers are versatile tools for space, variously used for remote sensing, interferometry and communications. ESA's Opto-Electronics Laboratory, at the Agency's ESTEC technical centre in Noordwijk, the Netherlands, specialises in assessing devices that generate, detect and manipulate light.
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