A novel low-cost material that can be used to create thermal imaging lenses has been found by researchers at Flinders University, pointing to new advanced manufacturing uses for this potent technology.
Many industries, including defense, security and surveillance, healthcare, electrical engineering, space exploration, and autonomous vehicle operation, use thermal and infrared imaging; however, the materials needed are expensive and become harder to source.
There is a need for more affordable alternatives, thus a multidisciplinary team from Flinders University working in chemistry and physics has found a solution in a brand-new polymer material consisting of sulfur and cyclopentadiene. According to reports, high-performance polymers have a special capacity for transmitting infrared light.
“The material combines high performance, low cost, and efficient manufacturing,” explains first author candidate Sam Tonkin in a recent research published in the journal Advanced Optical Materials.
“It has the potential to broaden the application of thermal imaging to new industries that were previously restricted by the high cost of germanium or chalcogenide lenses.” “This is a rapidly developing field with exciting developments in the coming years,” he says.
In the petroleum refining process, millions of tons of sulfur are created. Geological deposits contain billions of tons. It is abundant and inexpensive.
In the process of refining petroleum, low-cost ingredients are also used to make cyclopentadiene.
Currently, germanium or chalcogenide glasses are employed to make the lenses for thermal imaging. Germanium is a rare element that is also quite expensive. Several thousand dollars can be spent on some germanium lenses.
Chalcogenide glasses have drawbacks as well. For instance, they frequently include harmful substances like selenium or arsenic.
Dr. Le Nhan Pham, a co-author and computational and physical chemistry researcher at Flinders University, claims that the reaction of sulfur and cyclopentadiene produces a black plastic with high infrared light transparency.
The light that thermal imaging cameras pick up on is this one.
“This novel material was designed to have a broad range of potential applications ranging from space engineering to military operations, as well as the civil and aerospace industries,” he explains.
The polymer can be molded into a variety of lenses, such as those used to magnify images in thermal cameras. Because it is black, the polymer can also be utilized to conceal and protect thermal imaging equipment. As a result, the polymer can be utilized as camouflage to conceal a surveillance camera.
Infrared light flows through the polymer, allowing an infrared camera to view through it. This characteristic is beneficial in defense operations as well as wildlife surveillance.
The polymer also has many other features:
- The material exhibits the highest documented long-wave infrared light transparency for a plastic.
- The basic ingredients are inexpensive: the building blocks for a 1 g lens cost less than one penny.
- The material can be quickly molded into various shapes, such as lenses. This is a faster procedure than conventional lens manufacturing, which relies on slow milling methods.
The study also disclosed several significant scientific achievements, such as a novel reactor built to facilitate the essential reaction. The ability to use the building components in gaseous form was a major hurdle. Other researchers in the field previously assumed that using gaseous monomers was impossible.
The research also includes quantum mechanical calculations to explain how and why the material is transparent to infrared light, which is used in thermal imaging. These discoveries will also be valuable in the future when designing new lenses with improved qualities.