Implementation of a Graphical User Interface for a Nitrogen-Vacancy Quantum Sensing Instrument
Heikkinen, Oskari (2025)
2025
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Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:amk-2025121536496
https://urn.fi/URN:NBN:fi:amk-2025121536496
Tiivistelmä
Nitrogen-Vacancy (NV) centers in fluorescent nanodiamonds (FNDs) have emerged as a powerful quantum sensing modality, particularly for detecting free radicals in biological systems via T1 relaxometry. However, transitioning this technology from experimental optical tables to clinical research environments requires a shift from laboratory scripts to robust, commercial-grade control software. This thesis presents the design and implementation of a prototype Graphical User Interface (GUI) for a quantum sensing device capable of single-cell analysis.
Developed using Python and the PyQt6 framework, the application utilizes multi-threaded architecture to ensure interface responsiveness while handling synchronous hardware operations. A logic-lock system was implemented to prevent conflicting function execution, ensuring system stability and measurement integrity. The software manages a complex hardware array via an I/O interface, managing laser control, single-photon detector readout, galvo-mirrors, and motorized positioning stages with nanometer precision.
Key features of the GUI include a dual-view display merging pixel-by-pixel confocal scans with brightfield camera feeds, automated mosaic imaging for large-area FND localization, and an autofocus algorithm optimized for diamond tracking. The system’s performance was validated through T1 relaxometry experiments, demonstrating a sensitivity to 1nM concentrations of Gadolinium. Resulting software significantly reduced experimental runtime compared to previous iterations and demonstrated crash-proof stability during testing. The system has been deployed to customers and is currently used in a research hospital to investigate oxidative stress markers in sepsis patients.
Developed using Python and the PyQt6 framework, the application utilizes multi-threaded architecture to ensure interface responsiveness while handling synchronous hardware operations. A logic-lock system was implemented to prevent conflicting function execution, ensuring system stability and measurement integrity. The software manages a complex hardware array via an I/O interface, managing laser control, single-photon detector readout, galvo-mirrors, and motorized positioning stages with nanometer precision.
Key features of the GUI include a dual-view display merging pixel-by-pixel confocal scans with brightfield camera feeds, automated mosaic imaging for large-area FND localization, and an autofocus algorithm optimized for diamond tracking. The system’s performance was validated through T1 relaxometry experiments, demonstrating a sensitivity to 1nM concentrations of Gadolinium. Resulting software significantly reduced experimental runtime compared to previous iterations and demonstrated crash-proof stability during testing. The system has been deployed to customers and is currently used in a research hospital to investigate oxidative stress markers in sepsis patients.