Reviewed by Lexie CornerJun 7 2024
An international team of researchers from the City University of New York, the University of Melbourne, RMIT University, and the ARC Centre of Excellence for Transformative Meta-Optical Systems (TMOS) created a lightweight, compact sensor system with infrared imaging capabilities. This sensor system could be easily mounted to a drone for remote crop monitoring. This research was published in the journal Nature Communications.
The flat-optics sensor system can rapidly switch between edge detection–imaging the outline of an object, such as a fruit–and extracting detailed infrared information. Image Credit: Lincoln Clark, TMOS
This invention might result in cheaper groceries. Farmers will be able to identify which crops require irrigation, fertilization, and pest management rather than adopting a one-size-fits-all strategy, potentially increasing harvests.
The sensor system can quickly transition between edge detection (imaging the shape of an object, such as a fruit) and extracting detailed infrared information, eliminating the need to generate vast amounts of data and use bulky external processors.
The ability to transition to a detailed infrared image is a recent advancement in the sector that could help farmers collect additional information when the remote sensor detects regions of possible pest infestation.
How Does the Sensor System Work?
The prototype sensor system, which includes a filter constructed of a thin layer of vanadium dioxide that can switch between edge detection and detailed infrared imaging, was designed by TMOS Chief Investigator Professor Madhu Bhaskaran and her team at RMIT, Melbourne.
Materials such as vanadium dioxide add a fantastic tuning capability to render devices ‘smart.’ When the temperature of the filter is changed, the vanadium dioxide transforms from an insulating state to a metallic one, which is how the processed image shifts from a filtered outline to an unfiltered infrared image.
Madhu Bhaskaran, Professor, The Royal Melbourne Institute of Technology
Bhaskaran added, “These materials could go a long way in futuristic flat-optics devices that can replace technologies with traditional lenses for environmental sensing applications–making them ideal for use in drones and satellites, which require low size, weight and power capacity.”
RMIT has a granted US patent and a pending Australian patent application for its process of making vanadium dioxide films, which might be used for various applications.
The lead author, Dr. Michele Cotrufo, noted the system’s capacity to transition between processing processes, such as edge detection and detailed infrared image capture.
While a few recent demonstrations have achieved analog edge detection using metasurfaces, most of the devices demonstrated so far are static. Their functionality is fixed in time and cannot be dynamically altered or controlled. Yet, the ability to dynamically reconfigure processing operations is key for metasurfaces to be able to compete with digital image processing systems. This is what we have developed.
Dr. Michele Cotrufo, Study Lead author, Advanced Science Research Center, City University of New York
Next Steps
Co-author and Ph.D. scholar Shaban Sulejman from the University of Melbourne said the filter’s design and materials made it suitable for mass production.
It also operates at temperatures compatible with standard manufacturing techniques, making it well-placed to integrate with commercially available systems and, therefore, move from research to real-world usage rapidly.
Shaban Sulejman, Study Co-Author and PhD Student, The University of Melbourne
Ann Roberts, TMOS Chief Investigator from the University of Melbourne, stated that flat optics technologies have the potential to change a wide range of sectors.
Traditional optical elements have long been the bottleneck preventing the further miniaturization of devices. The ability to replace or complement traditional optical elements with thin-film optics breaks through that bottleneck.
Ann Roberts, TMOS Chief Investigator, University of Melbourne
Journal Reference:
Cotrufo, M., et al. (2024) Reconfigurable image processing metasurfaces with phase-change materials. Nature Communications. doi:10.1038/s41467-024-48783-3