Underwater Laser Imager Uses Separate Platform Approach
PATUXENT RIVER, Md., May 14, 2013 — In underwater laser imaging systems, the transmitter and receiver usually are on the same platform, but a new method that places the devices on separate platforms could enhance their performance in murky water.
“It’s a new way of thinking about things,” said Dr. Linda Mullen, a Naval Air Warfare Center Aircraft Division (NAWCAD) engineer who developed the method with Alan Laux. “In acoustics and radar, they’ve been doing these kinds of approaches for a long time. This is very new for optics.”
The method — which could enhance fleet activities such as seafloor mapping and underwater mine detection — encodes a laser with a radar signal, enabling better image quality and larger operating ranges than traditional underwater optical imaging systems. The remote receiver wirelessly collects the radar-encoded laser light from the transmitter and translates the information, while an image processor turns the digitized signal into an image.
“We program the laser with information about how the laser is scanning the object,” Mullen said of the project, which was developed two years ago and patented in February. “The light reflecting off the object and the surrounding environment contains all the information needed to accurately create an image.”
With the separate platform approach, the receiver can potentially be airborne, shipboard or on another underwater stand — a first for optics imaging. It also makes it possible to use a smaller platform, enabling the light source to be closer to objects without stirring up as much sediment. Less sediment means better visibility, an important factor in activities such as minesweeping, which depends on the ability to detect mines without triggering them.
Commercial uses for the technology also exist. With fewer limitations in shallow water than traditional sonar, the underwater laser imaging can approach objects from a single direction.
“There are scenarios when you have to start thinking out of the box,” Mullen said. "Otherwise, you are going to be limited. You won’t be able to get to see what you want to see.”
After recent testing, Maryland law enforcement officials expressed interest in using the technology to support search and recovery missions.
NAWCAD currently is pursuing industry partners to assist in bringing the technology to market.
For more information, visit: www.navair.navy.mil
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