February 27, 2013
Looking Through Fire: Hologram Could Help Firefighters Find Victims
[WATCH VIDEO: Video Comparing Imaging Systems]
Lee Rannals for redOrbit.com — Your Universe Online
Scientists developed a new imaging technique with the potential to allow firefighters to see through flames to find people in need of rescue. The new technique uses infrared (IR) digital holography to look through chaotic configurations like flames, and capture hidden details about what lies beyond.
Current IR camera technology allows firefighters to see through smoke, but these instruments are blinded by the infrared radiation that flames emit. Flames overwhelm the sensitive detectors, limiting their use in the field.
Researchers created a system using a specialized lens-free technique capable of coping with the flood of radiation from an environment consumed by flames and smoke.
"IR cameras cannot 'see' objects or humans behind flames because of the need for a zoom lens that concentrates the rays on the sensor to form the image," says Pietro Ferraro of the Consiglio Nazionale delle Ricerche (CNR) Istituto Nazionale di Ottica (INO) in Italy. By eliminating the need for the zoom lens, the new technique avoids this drawback.
He says it became clear to the researchers that they had a piece of technology that could potentially be used by emergency responders and firefighters at a fire scene to see through smoke, without the flames interrupting their sight.
"Perhaps most importantly, we demonstrated for the first time that a holographic recording of a live person can be achieved even while the body is moving," said Ferraro.
Holography is used to create a hologram, or a 3D image of an object, which has inspired future communication concepts in movies like Star Wars. When creating a hologram, a laser beam is split into two and the object beam is shown onto the object being imaged. When the reflected object beam and the reference beam are combined, they create an interference pattern that encodes the 3D image.
The researchers´ new system allows a beam of infrared laser light to be widely dispersed throughout a room, cutting through both smoke and flames, but reflecting off objects and people to give firefighters a better perspective of their surroundings.
Next, the researchers said they need to develop a portable tripod-based system for both the laser source and the IR camera. They will also be looking to see if the system could be installed inside buildings or tunnels, or whether it could be used in the biomedical field.
"One further application would in critical transport infrastructures such as highway tunnels, undersea tunnels, train tunnels for continue monitoring in case of fire accident and or to increase remote surveillance (sic)," Ferraro told redOrbit.
He also mentioned the technology could be used in oil platforms, in case of fires, so operators would be able to see through flames to find what is happening.
"Since Digital Holography at IR can be also useful for mechanical testing, it would be very useful for study mechanical stress and failure of materials and components in real-time and in-situ in mechanical stress under 'burning' conditions (sic)," he told redOrbit. "Many materials and component needs certification in burning conditions from house furnitures to aerospace industry."
Next, Ferraro said the team plans to make experiments and investigations on real-scale fire scenarios. He said they already tested the technology in the lab, so now they hope to test it in the field.
During the next phase of testing, the researchers want to develop two different types of prototypes, including one for fixed installation and one for mobile application. Also, Ferraro told redOrbit that they want to explore and investigate IR laser sources and new detectors based on graphene.
He said they want to "develop efficient algorithms for processing in quasi real-time acquired digital holograms for 3D scene display and rendering," as well as "develop efficient protocols and algorithms for transmitting digital hologram with high resolution in remote control and command centers."