NAWCAD engineers encode additional info onto laser beam for underwater imaging
Patuxent River, MD--Two engineers at the U.S. Naval Air Warfare Center Aircraft Division (NAWCAD), Linda Mullen and Alan Laux, have invented a method to encode a laser with a radar signal to improve the performance of underwater imaging systems in murky water. The invention could help in seafloor mapping and detecting underwater mines.
“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. “Therefore, the light reflecting off the object and the surrounding environment contains all the information needed to accurately create an image.”
A typical underwater laser imaging system has the transmitter and receiver on the same platform. Mullen and Laux tailored their imaging system by placing the transmitter and receiver on separate platforms. 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.
"It’s a new way of thinking about things,” Mullen said. “In acoustics and radar, they’ve been doing these kinds of approaches for a long time. This is very new for optics.”
Their method allows for better image quality and larger operating ranges than traditional underwater optical imaging systems. With the separate platform approach, the receiver can potentially be airborne, shipboard or on another underwater stand—a first for optics imaging.
Smaller platform
It also enables a smaller platform, which allows the light source to get closer to the object in question 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 inadvertently triggering them.
Commercial uses for the technology exist as well. During one recent test, Maryland law enforcement officials expressed interest in using the technology to help with search and recovery efforts. Underwater laser imaging has the advantage of approaching objects from a single direction and has fewer limitations in shallow water than traditional sonar.
NAWCAD is looking for industry partners to assist in the commercialization of this technology; for more info, call the NAWCAD Technology Transfer Office at 301-342-1133 to discuss opportunities to collaborate or license the technology.
Source: http://www.navair.navy.mil
John Wallace | Senior Technical Editor (1998-2022)
John Wallace was with Laser Focus World for nearly 25 years, retiring in late June 2022. He obtained a bachelor's degree in mechanical engineering and physics at Rutgers University and a master's in optical engineering at the University of Rochester. Before becoming an editor, John worked as an engineer at RCA, Exxon, Eastman Kodak, and GCA Corporation.