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The display utilises an ionisation effect which occurs when a beam of laser light is focused to a point in air. The laser beam itself is invisible to the human eye but, if the intensity of the laser pulse exceeds a threshold, the air breaks down into glowing plasma that emits visible light.

The required intensity can only be achieved by very short, powerful laser pulses – each plasma dot, or "flashpoint", lasts for only about a nanosecond. But the resulting image appears to last longer due to persistence of vision. As with film and television, the impression of a continuous image is maintained by refreshing the flashpoints.