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New technology promises cheaper infrared cameras

Driving a car in the country at night can be a scary. The combination of poor visibility and animals or other hard to spot obstacles on the road poses an obvious threat to both the car and its occupants. Some luxury models now have the option of forward looking infrared (FLIR) night vision systems, so you can see the animal in time to swerve. Unfortunately these systems are pricey, even as an aftermarket add-on, but that may soon change through the work of researchers at the Fraunhofer Institute for Mechanics of Materials (IWM) in Freiburg, Germany. The researchers have invented a way of bringing down the cost of the infrared lenses in FLIR systems down by 70 percent - opening the way to cheap FLIR cameras for the mass market.

Currently, lenses are made of crystalline materials like germanium, zinc selenide or zinc sulfide. These are very expensive and require costly grinding and polishing, so the IWM team went in search of a cheaper material that used cheaper processing. The key to this was replacing traditional material with amorphous chalcogenide glass. This is glass that contains cheaper elements like sulfur, selenium or tellurium and is commonly used in lasers and CDs and DVDs.

“Its softening temperature – that is, the temperature at which it can be formed – is low. Therefore, we can form it using non-isothermic hot stamping,” says Dr. Helen Müller, scientist at IWM.

“Non-isothermic hot stamping” means that instead of grinding and polishing, the lens are formed in a press that researchers describe as a “waffle iron.” Two heated plates contain a lens mold. The hot glass is clamped between these and then allowed to cool. When removed, there is a perfect lens that has the same optical qualities as a ground and polished one.

Source: gizmag.comAdded: 13 August 2012