The WatchStander system was originally developed for the US naval fleet but has been modified and adapted over the past two years for use by commercial vessels, cruise ships and yachts. A significant advance in anti-pirate technology, WatchStander is a fully automated and integrated system that detects and identifies pirates before launching a series of non-lethal but highly effective counter measures.
It is currently undergoing an Audit and Performance Assessment by maritime security and operations consultants from Flag Victor. The system has already received praise from several senior naval personnel, including Admiral Mark Fitzgerald (Ret.), former Commander of the US Naval Forces Europe and US Naval Forces Africa, who recently joined the company as a special adviser. Admiral Mark Fitzgerald stated “I’ve been aware of this type of surveillance, recognition and defence technology for some time. The fact that it can now be used to defend the world’s commercial fleets is a major leap forward in the fight against maritime piracy. It is a perfect example of how military innovation can crossover to deliver a very important new civil purpose. The development teams have shown the benefits to be derived from collaboration.”
The founder and driving force behind WatchStander, David Rigsby, has over thirty years’ experience working in the perimeter protection and defence industry sector. He has worked closely with his research partners at the Applied Research Laboratory of Pennsylvania State University to modify WatchStander for commercial use and holds an exclusive licence to take it to the global commercial shipping market.
WatchStander can be quickly installed on vessels of all sizes and provides a legal and non-lethal answer to the growing problem of violent attacks on ships and their crews. The system works by accurately identifying pirate craft at long range and launching an automatic and unmanned defence at several miles range that becomes progressively more robust if the attacker fails to withdraw.
Tests have shown WatchStander to be accurate and reliable in identifying pirate craft and distinguishing them from other non-threatening vessels. A series of successful on-water demonstrations showing WatchStander at work in real life simulations has recently taken place in Chesapeake Bay, Maryland. These were conducted under scrutiny by independent observers from the commercial shipping industry, prominent US governmental officials and representatives of The Applied Research Laboratory at Penn State University which has a long and established partnership with the US Navy on the development of defence related technologies.
Source: WatchStander
Officer of the Watch 
What is it? Acoustic, Laser? video does not work.
Taken from the Watchstander website:
So it must be using both accoustic means and some kind of laser or other light technology to blind the approaching pirates.
The video has been removed since it has become “private” on the youtube.