NTU SPMS Researchers Pioneer Breakthrough in Label-Free Microscopy
Researchers at Nanyang Technological University’s School of Physical and Mathematical Sciences have unveiled a new technique called limited-size object microscopy, or LSOM. This method enables label-free, far-field super-resolution imaging of objects confined to a known small area, achieving resolutions of λ/7 in two dimensions and λ/8 in one dimension. The development addresses long-standing challenges in optical imaging by leveraging prior knowledge of an object’s limited size rather than relying on fluorescent labels or near-field probes.
The work, conducted in collaboration with the University of Southampton, was published in the February 2026 issue of Nature Photonics. It represents a significant advance for fields requiring high-resolution imaging without altering samples through labeling, including materials science, nanotechnology, and certain biological applications where labels may interfere with natural processes.
Understanding the Science Behind LSOM
Traditional optical microscopy is limited by the diffraction of light, typically resolving features no smaller than roughly half the wavelength of the illuminating light. LSOM overcomes this by representing the coherently scattered field from the object using Slepian–Pollak functions, a family of prolate spheroidal wavefunctions. These mathematical tools efficiently capture the information from objects known to occupy a limited spatial extent.
The technique begins with illuminating the sample with coherent light and capturing the scattered field. By incorporating the prior knowledge that the object lies within a bounded region, the system reconstructs a super-resolved image. Experimental demonstrations have confirmed the method works in both two- and one-dimensional configurations, opening pathways for applications in nanoscale characterization.
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Key Contributors and Institutional Context at NTU
Dr Taeyong Chang, a postdoctoral researcher at SPMS, served as lead author. The project was supervised by Dr Giorgio Adamo, senior principal research fellow at SPMS, and Professor Nikolay Zheludev, a prominent figure in nanophotonics. Their work builds on NTU’s established strengths in photonics and materials research, supported by the university’s Centre for Disruptive Photonic Technologies.
NTU’s commitment to interdisciplinary research environments has enabled such advances. The School of Physical and Mathematical Sciences provides dedicated facilities and collaborative opportunities that attract early-career researchers from around the world. This ecosystem supports the training of PhD students and postdoctoral fellows who contribute directly to high-impact publications.
Implications for Higher Education and Research Training in Singapore
The LSOM breakthrough highlights Singapore’s growing role as a hub for advanced photonics research. Universities such as NTU play a central role in preparing the next generation of scientists through hands-on laboratory experience and international collaborations. Students and early-career researchers gain exposure to cutting-edge techniques that translate directly into skills valued across academia and industry.
Singapore’s higher-education sector benefits from sustained investment in research infrastructure. Programmes at NTU and peer institutions emphasise both fundamental discovery and applied outcomes, aligning with national priorities in technology and innovation. The visibility of such publications strengthens the attractiveness of Singapore-based doctoral and postdoctoral positions for talent seeking impactful research environments.
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Broader Applications and Future Directions
LSOM’s label-free nature makes it particularly suitable for imaging delicate or dynamic samples where introducing fluorescent markers could alter behaviour. Potential uses span semiconductor inspection, nanomaterial characterisation, and non-invasive studies in soft matter. Continued refinement could extend the method to more complex, three-dimensional objects or integrate it with existing scanning microscopy platforms.
Future research at NTU and partner institutions is expected to explore hybrid approaches combining LSOM with machine-learning reconstruction algorithms. These developments could further enhance resolution and speed, broadening accessibility for research groups worldwide.
Supporting Singapore’s Research Ecosystem
Breakthroughs like LSOM reinforce Singapore’s strategy of fostering world-class research talent. The country’s universities maintain strong links with industry and international partners, creating pathways for knowledge transfer. Administrators at NTU and similar institutions continue to expand opportunities for collaborative projects that position Singapore graduates competitively in global academic and industrial markets.
PhD-track candidates interested in photonics and nanoscale imaging now have additional reasons to consider Singapore-based programmes. The combination of state-of-the-art facilities, experienced supervisors, and a supportive funding environment accelerates career development in these specialised fields.
