Peering into the Nanoworld: The Revolutionary Fiber Resolution Targets (FiRsT)

Written and Compiled by: Komal Agarwal and Biswajoy Ghosh 

Microscopes have long been the gatekeepers to a world invisible to the naked eye, revealing the intricate details of everything minute in our world. From the structure of a cell to the composition of materials, microscopes have been pivotal in driving some of the most groundbreaking discoveries to date. In modern times, these instruments have become an essential tool across various fields, including the pharmaceutical industry, hospitals, life sciences, material sciences, and education. As microscopy technology has advanced, we’ve been able to see details as small as tens of nanometres, giving rise to what are often referred to as optical nanoscopes.

However, as we delve deeper into the microscopic world, the distinction between what we observe and the underlying reality becomes increasingly ambiguous. This is where the importance of resolution references, or resolution targets, comes into play. These targets, with their known geometrical and optical properties, serve as benchmarks to verify, calibrate, and troubleshoot the resolution—the ability to distinguish the smallest detail—and any artifacts that microscopes may produce.

Despite their critical role, the existing resolution targets have struggled to keep pace with the evolving demands of advanced microscopy techniques. There’s a growing need for targets that not only provide a standard for resolution but also encompass other key optical features, such as refractive index contrast (RIC). Addressing this need, we introduce the Fiber Resolution Targets (FiRsT), a pioneering resolution target that can characterize and calibrate multiple optical nano/microscopes and is the first to support a range of RIC values.

The concept of FiRsT germinated in December 2018 in Singapore, during a casual scientific discussion over coffee between its inventors. The actual technology development, however, commenced in 2021 at UiT in Norway, when Komal Agarwal arrived as a postdoctoral researcher. Fueled by a transdisciplinary grant for young researchers from Digital Life Norway (DLN), Komal was inspired to embark on this innovative project.

In 2023, a patent application (Patent Application 2309111.9) for FiRsT was filed by its inventors, Komal Agarwal, Krishna Agarwal, and Biswajoy Ghosh. Since then, FiRsT has not only captured the imagination of the scientific community but has also garnered significant support in the form of the RCN Qualification grant and the RCN proof-of-concept innovation grant.

FiRsT stands as a testament to the collaborative spirit of science and the relentless pursuit of precision in the microscopic realm. By providing a more comprehensive and versatile resolution target, FiRsT is set to enhance the capabilities of microscopes and, in turn, our understanding of the nanoworld. As we continue to push the boundaries of what we can see and understand, tools like FiRsT will be at the forefront, ensuring that our vision remains clear and our discoveries remain true.