Thermal cameras, reminiscent of gadgets from spy thrillers, have the remarkable ability to “visualize” heat by converting infrared radiation into images. By detecting the infrared light emitted by animals, vehicles, electrical equipment, and even humans, these cameras have found specialized applications across various industries.
However, the widespread adoption of thermal imaging technology in consumer products such as self-driving cars or smartphones has been hindered by its prohibitive cost.
At Flinders University, our dedicated team has been tirelessly working towards democratizing this technology and transforming it into something accessible to everyone, rather than confined to the realm of espionage movies. We have successfully developed an affordable thermal imaging lens that holds the potential to be scaled up and integrated into the daily lives of ordinary individuals. The details of our breakthrough can be found in the esteemed journal Advanced Optical Materials.
Thermal imaging across industries
The applications of thermal imaging extend across various fields, showcasing its versatility and significance. One notable domain where this technology finds immense value is in surveillance and security. The ability to detect the heat signatures of individuals makes thermal imaging an invaluable tool for defense forces worldwide, including those in Australia.
In the realm of medicine, thermal cameras have proven their worth by aiding in the non-invasive detection of tumors. As tumors exhibit higher metabolism and temperature compared to healthy tissues, thermal imaging can identify areas with increased heat, thus assisting in the early diagnosis and treatment planning.
Furthermore, thermal imaging holds great importance in space exploration. Its capability to capture images of distant stars, galaxies, and planets is particularly valuable since infrared light can effectively penetrate dust clouds, surpassing the limitations of visible light. The renowned NASA James Webb Space Telescope relies on infrared imaging, enabling us to explore previously uncharted realms of the universe characterized by far “redder” wavelengths.
Addressing the high-cost conundrum
The potential applications of thermal imaging are vast and varied, but their realization is often hindered by the high production costs associated with this technology.
A significant contributor to the expense lies in the specialized lenses required for thermal cameras. These lenses must possess unique properties that enable them to interact with infrared radiation in a manner not possible with standard lenses.
Typically, infrared radiation is absorbed by most glasses and plastics, necessitating the use of expensive materials like germanium or zinc selenide. However, the manufacture and maintenance of these materials pose challenges. Germanium is a scarce and critical element, while zinc selenide contains toxic elements.
To address this lens-related obstacle, our team at Flinders University undertook a proactive approach. We successfully developed a novel polymer using sulfur and cyclopentadiene, two abundant and low-cost building blocks.
The raw materials required for our lens cost less than one cent per lens, a stark contrast to the exorbitant prices associated with germanium lenses, which can run into thousands of dollars.
Moreover, our sulfur-based lens can be molded and cast into complex shapes using established techniques from the plastics industry. These techniques are simpler and require less energy compared to conventional methods for creating infrared lenses. As a result, the cost is further reduced, and the polymer becomes highly scalable.
The breakthrough in developing this material centered around utilizing cyclopentadiene as a gas during the reaction with sulfur. This allowed precise control over the composition of the resulting polymer, resulting in a lens with enhanced capabilities specifically tailored for thermal imaging.
Despite its complete opacity to visible light, our polymer boasts the highest reported long-wave infrared transmission among all reported plastics. This exceptional characteristic enables its compatibility with thermal imaging cameras, thereby offering a promising solution to the lens cost conundrum.
Possible applications
The advent of this new material paves the way for a multitude of previously unattainable thermal imaging applications.
In the realm of transportation, self-driving cars can leverage this technology to detect pedestrians and vehicles, even in challenging conditions like low light or fog. Similarly, the agricultural sector stands to benefit as thermal imaging can be employed for monitoring irrigation systems and assessing crop health. The affordability of this solution would be a boon for farmers.
Furthermore, the lightweight nature of the new lens makes it ideal for aerial imaging using drones. This opens up possibilities for applications in fields such as surveying, environmental monitoring, and infrastructure inspection.
Integration into consumer electronics represents another exciting avenue. Imagine the inclusion of thermal imaging capabilities in smartphones, computers, and home automation systems, enabling users to capture thermal images or videos effortlessly. Additionally, this technology could find utility in creating advanced smoke alarms that detect thermal anomalies.
The advancements achieved through this study have significantly reduced the barriers to adopting thermal imaging technology, potentially revolutionizing its use in our daily lives.
Source: The Conversation