Researchers from the Middle East Technical University in Ankara, Turkey, have developed a groundbreaking real-time control and automation framework for acousto-holographic microscopy, addressing significant bottlenecks in cell biology research. The team, led by Hasan Berkay Abdioğlu and including Yağmur Işık, Mustafa İsmail İnal, Nehir Serin, Kerem Bayer, Muhammed Furkan Koşar, Taha Ünal, and Hüseyin Üvet, presents a fully automated closed-loop Digital Holographic Microscopy (DHM) system designed for high-throughput mechanical characterization of biological cells.
The manual operation of microscopes for repetitive tasks in cell biology has long been a bottleneck, consuming valuable expert time and introducing human error. Automation is crucial to overcoming these challenges. While DHM offers powerful, label-free quantitative phase imaging (QPI), its inherently noisy and low-contrast holograms make robust autofocus and object detection difficult. The researchers have tackled this issue by integrating automated serpentine scanning, real-time YOLO-based object detection, and a high-performance, multi-threaded software architecture. This architecture uses pinned memory and SPSC queues, enabling the GPU-accelerated reconstruction pipeline to run fully in parallel with the 50 fps data acquisition, adding no sequential overhead.
A key contribution of this research is the validation of a robust, multi-stage holographic autofocus strategy. The team demonstrated that a selected metric, based on a low-pass filter and standard deviation, provides reliable focusing for noisy holograms where conventional methods like Tenengrad and Laplacian fail entirely. Performance analysis of the complete system identified the 2.23-second autofocus operation, rather than reconstruction, as the primary throughput bottleneck, resulting in a 9.62-second analysis time per object.
This work delivers a complete functional platform for autonomous DHM screening and provides a clear, data-driven path for future optimization. The researchers propose a hybrid brightfield imaging modality to address current bottlenecks, paving the way for more efficient and accurate cell biology research. The implications for the marine sector are significant, particularly in the study of marine microorganisms and plankton, where high-throughput, automated imaging can enhance our understanding of marine ecosystems and support environmental monitoring and conservation efforts. Read the original research paper here.