Low-cost sulfur lens enables cheaper IR thermal imaging cameras

26 Feb 2026

Development by Flinders University could cut need for costly lenses based on silicon and rare earths.

The days of dropping a thermal imaging camera and replacing an expensive lens are coming to an end with a new repairable lens developed by Flinders University scientists.

A high-performance lens for infrared cameras invented by researchers at Flinders University, Adelaide, Australia, offers a lower cost, more sustainable option for applications based on thermal imaging cameras, including security and surveillance, medicine, defense, and autonomous vehicles.

The infrared thermal imaging lens, made from readily available and low-cost sulfur and other materials, replaces the need for traditional lenses that use relatively expensive elements such as silicon and germanium, according to new research published in Nature Communications.

“As demand for thermal imaging in consumer products rises, there is an increasing need for lower-cost optics. Our polymer lens provides a more sustainable alternative to more expensive inorganic materials such as germanium, silicon or chalcogenide glass,” said senior author and project director Prof. Justin Chalker, from Flinders University’s College of Science and Engineering.

The polymer, which can be moulded like a plastic, is made from sulfur and an organic co-monomer material. Millions of tonnes of surplus sulfur are produced every year, said Professor Chalker, “and the goal is to convert this abundant byproduct from petroleum refining into value-added materials and sustainable technologies”.

He added, “In fact, the raw materials used to make this new lens can cost less than 1 cent per unit, so it represents an extremely cost effective, competitive alternative for the thermal camera and sensor market.”

‘Increasing demand for low-cost optics’

First author Dr Samuel Tonkin says the latest advances of the new lens will expand its appeal and use in consumer products such as smartphone IR cameras, fire detectors, driver-assist technology to detect pedestrians and animals at night and energy-saving air-conditioners which increasingly rely on thermal imaging.

“As the prevalence of thermal imaging in consumer products increases, there is increasing demand for lower-cost optics,” said Dr Tonkin, a Flinders University PhD graduate from the Chalker Lab. “This pioneering Flinders technology addresses the challenges by being low cost, sustainable, repairable and recyclable.”

“They can be made relatively quickly compared to the more expensive materials, such as germanium, which take time to run through milling processes and cannot be repaired if damaged. From the first time we mounted a lens on a thermal camera and captured an image, seeing the expanding application of our research is exciting.”

The research team – including Flinders University coauthor Dr Harshal Patel – is working with collaborators at NASA, including another coauthor Dr Tilak Hewagama, to guide its use in imaging applications relevant to planetary science.

“This research is another big step forward in performance for this class of polymers,” saud Dr Patel. “Once these imaging systems reach consumer-level prices, they may be commonplace in fire detection systems, smart appliances, and other technologies. I’ll personally be using them to search for wildlife.”