London, August: The US Defense Advanced Research Projects Agency (DARPA) is turning to blue lasers to establish contact with submarines, as they penetrate water more effectively.
The water that hides enemy submarines also makes it hard to contact the friendly ones from the air - unless they surface.
According to a report in New Scientist, reaching submerged subs has required giant transmitters sending very low-frequency radio waves, which limits data transmission speeds, until the development of the blue lasers.
It has long been known that blue light penetrates water well.
DARPA tried to develop blue laser links to subs around 1980, but failed as the lasers available were inefficient.
DARPA’s fresh shot utilizes new compact lasers that emit blue light, and receivers with filters which transmit that wavelength and block any background light.
Fitting them in planes and ships should provide a high-bandwidth link with allied subs.
ANI
First Published: Wednesday, August 26, 2009, 13:29