Firefighters could be helped by holograph technology

Infra-red holography could be more useful than the camera imagery currently used by firefighters searching for people trapped in burning buildings, researchers in Italy say.

They have built an imaging system that uses an infra-red laser to penetrate areas of thick smoke and flames.

The beam reflects off any objects, including people, within the area.

That data is then decoded by an imager to create a 3D model of everything inside the room.

Infra-red (IR) camera monitors currently used by firefighters require lenses that can be blinded by intense fire, said researcher Pietro Ferraro, of the Consiglio Nazionale delle Ricerche (CNR) Istituto Nazionale di Ottica in Italy.

"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," he said.

"It became clear to us that we had in our hands a technology that could be exploited by emergency responders and firefighters at a fire scene to see through smoke without being blinded by flames, a limitation of existing technology."

Mr Ferraro added that fire victims who were moving could also be picked up by the system.

"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."

Other potential applications include monitoring breathing and cardiac activity, said Mr Ferraro - but the next step for the researchers was to make the technology more portable.

The research has been published in journal Optics Express.