"Engage deflector shields!" is a command often heard on the bridge of sci-fi spaceships locked in battle, but could such defensive contraptions actually work? Scientists at BAE Systems believe a new type of directed energy laser and lens system that manipulates the atmosphere could make such devices a reality, and in as little as fifty years from now.
Knownas the Laser Developed Atmospheric Lens (LDAL) concept, it works by simulatingnaturally occurring phenomena to temporarily alter small parts of the Earth'satmosphere to create lens-like structures that magnify or alter the path ofelectromagnetic waves, including radio signals and light. According to BAE, alens generated in this way could be used as a type of deflector shield toprotect aircraft, land vehicles, troops, and ships from assault by futurehigh-powered laser weapons (such as future versions of Lockheed-Martin's ADAM laser weapon system).
LDAL'sprime purpose, however, is to provide better electromagnetic communications bycreating various naturally-occurring effects, such as the reflective propertiesfound in the ionosphere and desert mirages. It does this by changing thereflective and refractive properties in targeted parts of the atmosphere usinga high-powered laser to create highly-reflective areas (like the ionosphere) orareas where light can be bent at will (in emulation of the desert mirage).
Inthis way, the LDAL system would allow, say, communications operating at veryhigh frequencies to be sent further than normally possible by recreating areas inthe atmosphere that gave it properties like the ionosphere. Or it could also beused to produce localized, Fresnel-lens-like refractive areas to bendelectromagnetic waves to a specific place, even when the direction was at acompletely different angle to the original waves.
The system would take advantage of what is known as the "Kerr Effect" (an optical phenomenon that occurs when intense light istransmitted through media such as glass or, in this case, gases in theatmosphere, that effectively alters the refractive index of that media) to temporarily ionize a small patch of atmosphere in a way thatallows the air to emulate mirrors, glass lenses, and structures like Fresnelzone plates that diffract light.
Other concepts, such as Northrop's system being developed for the US Air Force, have been mooted to control laser weapons, but this seems to be the first instance where a laser system has been proposed to create a shield to protect from laser weapon assaults. Though still very much a concept, it is this type of evaluation of what may be physically possible that is needed to spur further research.
"Workingwith some of the best scientific minds in the UK, we're able to incorporateemerging and disruptive technologies and evolve the landscape of potentialmilitary technologies in ways that, five or ten years ago, many would neverhave dreamed possible," said Professor Nick Colosimo, BAE Systems'Futurist and Technologist.
The video below from BAE Systems illustrates the concept.
Source: BAE Systems
