2025

Özüm Emre Aşırım, Robert Huber, and Christian Jirauschek,
Ultrashort Power-Dips in Fourier Domain Mode-Locked Lasers: Impact of Picosecond Carrier Recovery, in 2025 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) , Jun.2025. pp. 1-1.
DOI:10.1109/CLEO/Europe-EQEC65582.2025.11109071
Bibtex: BibTeX
@INPROCEEDINGS{11109071,
  author={Aşırım, Özüm Emre and Huber, Robert and Jirauschek, Christian},
  booktitle={2025 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)}, 
  title={Ultrashort Power-Dips in Fourier Domain Mode-Locked Lasers: Impact of Picosecond Carrier Recovery}, 
  year={2025},
  volume={},
  number={},
  pages={1-1},
  abstract={Fourier domain mode-locked (FDML) lasers are widely used in applications requiring high-speed wavelength sweeps and reliable spectral stability, such as optical coherence tomography (OCT) [1]. In this study, we explore the steady-state behavior of FDML lasers when the carrier lifetime of the semiconductor optical amplifier (SOA) is reduced to one picosecond-a scenario that can enable reduced intensity noise, improved coherence, and higher sweep speed, achievable with advanced quantum-well or quantum-dot SOAs, opening possibilities for next-generation FDML lasers [2], [3]. In previous studies, SOA carrier lifetimes longer than 70 picoseconds yielded irregular dips (holes) with varying shape, amplitude, and duration in the output power pattern, hindering beam coherence except under ultra-stable conditions [1,3-5]. Our latest simulations, which align with experimental findings in the detection and profiling of such dips [3]–[5], reveal that a 1 ps carrier lifetime improves stability and coherence but leads to emergence of consistent ultrashort, sinc-like power dips (Fig. 1, middle) for high output powers, which are almost uniform in duration (Fig. 1, right). The density of these dips increases as the output power is raised toward the upper practical limit. Based on foundational FDML laser theory [5]–[6], Equations (1)-(3) explain the formation of these ultrafast dips. At high photon flux, rapid gain depletion causes a sharp drop in carrier density $(N)$, generating a dip. Given the ultrashort carrier lifetime $(\tau_{c})$, the carriers recover quickly after depletion, restoring gain for the next dip. The time-delayed feedback term in Equation (2) represents light from previous round trips interacting with the restored carriers, amplifying the dips.},
  keywords={Semiconductor optical amplifiers;Laser mode locking;Power amplifiers;Coherence;Laser feedback;Laser stability;Stability analysis;Mathematical models;Charge carrier lifetime;Power generation},
  doi={10.1109/CLEO/Europe-EQEC65582.2025.11109071},
  ISSN={2833-1052},
  month={June},}
Marie Klufts, Wolfgang Draxinger, Simon Lotz, and Robert Huber,
1.7MHz, 840nm swept-source ophthalmic OCT, in Ophthalmic Technologies XXXV , Daniel X. Hammer and Derek Nankivil and Yuankai K. Tao, Eds. SPIE, Mä.2025. pp. 1330004.
DOI:10.1117/12.3045055
Bibtex: BibTeX
@inproceedings{10.1117/12.3045055,
author = {Marie Klufts and Wolfgang Draxinger and Simon Lotz and Robert Huber},
title = {{1.7MHz, 840nm swept-source ophthalmic OCT}},
volume = {13300},
booktitle = {Ophthalmic Technologies XXXV},
editor = {Daniel X. Hammer and Derek Nankivil and Yuankai K. Tao},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1330004},
keywords = {swept source, SS-OCT, FDML , Retinal imaging, ophthalmic imaging, OCT, 850 nm, short wavelength},
year = {2025},
doi = {10.1117/12.3045055},
URL = {https://doi.org/10.1117/12.3045055}
}
Sazgar Burhan, Berenice Schulte, Madita Göb, Awanish Pratap Singh, Bayan Mustafa, Simon Lotz, Wolfgang Draxinger, Philipp Lamminger, Yasmeine Saker, Tim Eixmann, Martin Ahrens, Marvin Heimke, Tillmann Heinze, Thilo Wedel, Maik Rahlves, Mark Ellrichmann, and Robert Huber,
Switchable lateral resolution real-time MHz-OCT rectoscopy for enhanced colorectal disease diagnosis, in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIX , Rainer A. Leitgeb and Yoshiaki Yasuno, Eds. SPIE, Mä.2025. pp. 1330512.
DOI:10.1117/12.3046222
Bibtex: BibTeX
@inproceedings{10.1117/12.3046222,
author = {Sazgar Burhan and Berenice Schulte and Madita G{\"o}b and Awanish Pratap Singh and Bayan Mustafa and Simon Lotz and Wolfgang Draxinger and Philipp Lamminger and Yasmeine Saker and Tim Eixmann and Martin Ahrens and Marvin Heimke and Tillmann Heinze and Thilo Wedel and Maik Rahlves and Mark Ellrichmann and Robert Huber},
title = {{Switchable lateral resolution real-time MHz-OCT rectoscopy for enhanced colorectal disease diagnosis}},
volume = {13305},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIX},
editor = {Rainer A. Leitgeb and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1330512},
abstract = {Endoscopic optical coherence tomography (OCT) offers in vivo live visualization of transmural structures with histological resolution, making it a valuable tool in medical imaging. In gastroenterology, OCT endoscopy is particularly advantageous for assessing rectal wall layers, providing superior axial and lateral resolution compared to conventional rectal endoscopic ultrasound. However, the large diameter and uneven colon surface present challenges for comprehensive imaging. Extending the OCT imaging range addresses this issue by enabling a thorough examination of the entire colon, facilitating the detection of surface polyps, tumors, and their infiltration depth. Once these regions of interest are identified, high-resolution imaging becomes essential for detailed evaluation. To meet these demands, this study integrates two different imaging modes, an extended-range mode, and a high-detail mode, within a rigid rectoscope. The extended-range mode enables visualization of deeper structures, while the high-detail mode enhances image quality for precise, contact-based assessments. The system allows seamless, real-time transitions between the modes using a 3.2MHz-OCT system and a fiber‑optic MEMS switch.},
keywords = {Optical Coherence Tomography, Megahertz OCT, Fourier Domain Mode Locking, Three-dimensional image acquisition, Rectal Imaging, Long-Range Imaging, Non-Invasive Diagnostic Imaging, Tumor Assessment},
year = {2025},
doi = {10.1117/12.3046222},
URL = {https://doi.org/10.1117/12.3046222}
}
Muhammad Asim Bashir, Marie Klufts, Simon Lotz, and Robert Huber,
Towards ultrahigh resolution MHz retinal SS-OCT: 187nm section-wise tuning of a FDML laser at 1050nm, in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIX , Rainer A. Leitgeb and Yoshiaki Yasuno, Eds. SPIE, Mä.2025. pp. 133050K.
DOI:10.1117/12.3046386
Bibtex: BibTeX
@inproceedings{10.1117/12.3046386,
author = {M. A. Bashir and M. Klufts and S. Lotz and R. Huber},
title = {{Towards ultrahigh resolution MHz retinal SS-OCT: 187nm section-wise tuning of a FDML laser at 1050nm}},
volume = {13305},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIX},
editor = {Rainer A. Leitgeb and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {133050K},
,
keywords = {wavelength-swept laser, FDML lasers, Optical coherence tomography, Fourier domain mode locked lasers, Broadband lasers, tunable lasers, swept lasers, swept source OCT},
year = {2025},
doi = {10.1117/12.3046386},
URL = {https://doi.org/10.1117/12.3046386}
}
Sazgar Burhan, Madita Göb, Mario Pieper, Tjalfe Laedtke, Thorge Grahl, Michael Münter, Hinnerk Schulz-Hildebrandt, Gereon Hüttmann, Peter König, and Robert Huber,
Large-area dynamic contrast MHz optical coherence tomography for label-free imaging of porcine tissue, in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIX , Rainer A. Leitgeb and Yoshiaki Yasuno, Eds. SPIE, Mä.2025. pp. 1330502.
DOI:10.1117/12.3046216
Bibtex: BibTeX
@inproceedings{10.1117/12.3046216,
author = {Sazgar Burhan and Madita G{\"o}b and Mario Pieper and Tjalfe Laedtke and Thorge Grahl and Michael M{\"u}nter and Hinnerk Schulz-Hildebrandt and Gereon H{\"u}ttmann and Peter K{\"o}nig and Robert Huber},
title = {{Large-area dynamic contrast MHz optical coherence tomography for label-free imaging of porcine tissue}},
volume = {13305},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXIX},
editor = {Rainer A. Leitgeb and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1330502},
abstract = {We demonstrate a 3.2 MHz-OCT system for inter-volumetric dynamic optical coherence tomography of ex vivo porcine kidney tissue. Employing a home-built Fourier Domain mode locking (FDML) laser with a 1310 nm wavelength, the system achieved a lateral resolution of 3.48 μm and a frame rate of 612 Hz. A motorized XYZ positioning stage enabled the precise acquisition of multiple volumes, which were seamlessly stitched together to generate a comprehensive dataset with a total area of 2.6 × 2.6 mm<sup>2</sup>. Validations against histological sections confirmed the system’s ability to visualize cellular tissue structures.},
keywords = {Optical Coherence Tomography, Megahertz OCT, Fourier Domain Mode Locking, Dynamic OCT, Functional OCT, Three-dimensional image acquisition, Tissue Dynamics, Kidney},
year = {2025},
doi = {10.1117/12.3046216},
URL = {https://doi.org/10.1117/12.3046216}
}
Nicolas Detrez, Dirk Theisen-Kunde, Wolfgang Draxinger, Thies Hörcher, Veit Danicke, Sazgar Burhan, Jessica Kren, Matteo Mario Bonsanto, Robert Huber, and Ralf Brinkmann,
Co-Robot Supported Air-Jet Based Optical Coherence Elastography Towards In-Situ Brain Tumor Tissue Delineation, in European Conferences on Biomedical Optics 2025 , Optica Publishing Group, 2025. pp. M3A.36.
DOI:10.1364/ECBO.2025.M3A.36
Datei: abstract.cfm
Bibtex: BibTeX
@inproceedings{Detrez:25,
author = {Nicolas Detrez and Dirk Theisen-Kunde and Wolfgang Draxinger and Thies H\"{o}rcher and Veit Danicke and Sazgar Burhan and Jessica Kren and Matteo Mario Bonsanto and Robert Huber and Ralf Brinkmann},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Coherence and statistical optics; Elastography; Modes; Optical coherence tomography; Phase; Phase measurement},
pages = {M3A.36},
publisher = {Optica Publishing Group},
title = {Co-Robot Supported Air-Jet Based Optical Coherence Elastography Towards In-Situ Brain Tumor Tissue Delineation},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-M3A.36},
doi = {10.1364/ECBO.2025.M3A.36},
abstract = {Accurate tumor delineation in neurosurgery is challenging. We developed an in-situ optical coherence elastography system using air-jet excitation and phase based full-range OCT. The challenges in transitioning from ex vivo to in-situ application are presented.},
}
Paul Strenge, Birgit Lange, Wolfgang Draxinger, Dirk Theisen-Kunde, Sonja Spahr-Hess, Matteo M. Bonsanto, Robert Huber, Ralf Brinkmann, and Heinz Handels,
Enhancing brain tumor detection using optical coherence tomography and variational autoencoders, in Medical Imaging 2025: Clinical and Biomedical Imaging , Barjor S. Gimi and Andrzej Krol, Eds. SPIE, 2025. pp. 134101P.
DOI:10.1117/12.3047226
Bibtex: BibTeX
@inproceedings{10.1117/12.3047226,
author = {Paul Strenge and Birgit Lange and Wolfgang Draxinger and Dirk Theisen-Kunde and Sonja Spahr-Hess and Matteo M. Bonsanto and Robert Huber and Ralf Brinkmann and Heinz Handels},
title = {{Enhancing brain tumor detection using optical coherence tomography and variational autoencoders}},
volume = {13410},
booktitle = {Medical Imaging 2025: Clinical and Biomedical Imaging},
editor = {Barjor S. Gimi and Andrzej Krol},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {134101P},
abstract = {Neurosurgical intervention is critical in brain tumor treatment, with long-term survival closely linked to the extent of tumor resection. The goal is to completely remove tumor tissue while preserving healthy tissue, a challenging task due to the diffuse nature of some brain tumors, such as glioblastoma, which infiltrate healthy tissue in ways that are difficult to distinguish histologically. Current intraoperative imaging techniques, including MRI and fluorescence microscopy, are limited in reliably identifying tumor tissue. Optical coherence tomography (OCT) offers a promising alternative, providing non-invasive, high-resolution cross-sectional images. This study investigates the use of a variational autoencoder (VAE) in combination with an evidential learning framework to enhance the classification of brain tissues in OCT images. The classification approach, applied to ex vivo OCT images captured at a wavelength of 1300 nm, achieved an average precision of 0.87 and a recall of 0.88 for the discrimination of healthy and tumorous brain tissue with consideration of prediction uncertainties. This method demonstrated improved discrimination between healthy white matter and tumor-infiltrated white matter compared to previous studies.},
keywords = {brain tumor, OCT, variational autoencoders, glioblastoma, classification, medical imaging, brain, evidential learning},
year = {2025},
doi = {10.1117/12.3047226},
URL = {https://doi.org/10.1117/12.3047226}
}
Svea Höhl, Tim Eixmann, Martin Ahrens, Noah Heldt, Peter König, Ori Katz, and Gereon Hüttmann,
Holoscopic Microendoscopy, Jan.2025. pp. W4D.2.
DOI:10.1364/ECBO.2025.W4D.2
Weblink: https://opg.optica.org/abstract.cfm?URI=ECBO-2025-W4D.2
Bibtex: BibTeX
@inproceedings{inproceedings,
author = {Höhl, Svea and Eixmann, Tim and Ahrens, Martin and Heldt, Noah and König, Peter and Katz, Ori and Hüttmann, Gereon},
year = {2025},
month = {01},
pages = {W4D.2},
title = {Holoscopic Microendoscopy},
doi = {10.1364/ECBO.2025.W4D.2}
}
Madita Göb, Sazgar Burhan, Gereon Hüttmann, and Robert Huber,
In vivo Megahertz Dynamic Optical Coherence Tomography of Human Skin, in European Conferences on Biomedical Optics 2025 , Optica Publishing Group, 2025. pp. Tu3C.4.
DOI:10.1364/ECBO.2025.Tu3C.4
Datei: abstract.cfm
Bibtex: BibTeX
@inproceedings{Gob:25,
author = {Madita G\"{o}b and Sazgar Burhan and Gereon H\"{u}ttmann and Robert Huber},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Clinical applications; Imaging techniques; In vivo imaging; Optical coherence tomography; Three dimensional imaging; Tissue characterization},
pages = {Tu3C.4},
publisher = {Optica Publishing Group},
title = {In vivo Megahertz Dynamic Optical Coherence Tomography of Human Skin},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-Tu3C.4},
doi = {10.1364/ECBO.2025.Tu3C.4},
abstract = {We demonstrate Megahertz optical coherence tomography (MHz-OCT) for in vivo skin imaging with dynamic contrast at different resolutions. This study presents recent advances and discusses challenges for clinical translation and real-time in vivo applications.},
}
Noah Heldt, Martin Ahrens, Mario Pieper, Robert Schönherr, Lucie Jeschke, Peter König, Marko Lampe, and Gereon Hüttmann,
Investigating dOCT signal origins and bringing a new contrast to fluorescence imaging, in European Conferences on Biomedical Optics 2025 , Optica Publishing Group, 2025. pp. S4B.1.
DOI:10.1364/ECBO.2025.S4B.1
Datei: abstract.cfm
Kimberley Lühring, Birgit Lange, Lion Schützeck, and Ralf Brinkmann,
Laser lithotripsy: the impact of beam profile and wavelength on stone ablation, in Advanced Photonics in Urology 2025 , Hyun Wook Kang and Ronald Sroka and Jian J. Zhang, Eds. SPIE, 2025. pp. 1329306.
DOI:10.1117/12.3041264
Bibtex: BibTeX
@inproceedings{10.1117/12.3041264,
author = {Kimberley L{\"u}hring and Birgit Lange and Lion Sch{\"u}tzeck and Ralf Brinkmann},
title = {{Laser lithotripsy: the impact of beam profile and wavelength on stone ablation}},
volume = {13293},
booktitle = {Advanced Photonics in Urology 2025},
editor = {Hyun Wook Kang and Ronald Sroka and Jian J. Zhang},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1329306},
abstract = {Thulium fiber lasers (TFL) with a peak power of 500W were introduced a few years ago for clinical use in laser lithotripsy of urinary stones. To compare the TFL with the current gold standard, the Ho:YAG laser, single pulse experiments were performed at 1.5J from different working distances using a 365μm fiber. For evaluation of the fragmentation properties of both laser systems, cuttlefish bone samples and glued BegoStone cylinders were ablated at 1.5J using different pulse durations. It was found that the TFL produced up to two times higher stone ablation compared to the Ho:YAG laser but showed significantly poorer results in fragmentation which might be explained by its lower peak power. Furthermore, the increase in the ablation efficiency of laser lithotripsy by adjusting the beam profile was investigated in this study. A series of measurements with annular and circular beam profiles of the same beam diameter was performed with the TFL. At a pulse energy of 1J the annular beam profile has removed 90% more stone volume with a single pulse.},
keywords = {laser lithotropsy, thulium fiber laser, beam profile, urolithiasis},
year = {2025},
doi = {10.1117/12.3041264},
URL = {https://doi.org/10.1117/12.3041264}
}
Wolfgang Draxinger, Simon Lotz, Allegra Behr, Madita Göb, and Robert Huber,
Lifting constraints on multi-kHz raster-line scanning frequency matching in multi-MHz Swept-Source OCT imaging systems, in European Conferences on Biomedical Optics 2025 , Optica Publishing Group, 2025. pp. W5D.5.
DOI:10.1364/ECBO.2025.W5D.5
Datei: abstract.cfm
Bibtex: BibTeX
@inproceedings{Draxinger:25,
author = {Wolfgang Draxinger and Simon Lotz and Allegra Behr and Madita G\"{o}b and Robert Huber},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Absolute distance measurement; Field programmable gate arrays; Imaging systems; Light sources; Scanners; Swept sources},
pages = {W5D.5},
publisher = {Optica Publishing Group},
title = {Lifting constraints on multi-kHz raster-line scanning frequency matching in multi-MHz Swept-Source OCT imaging systems},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-W5D.5},
doi = {10.1364/ECBO.2025.W5D.5},
abstract = {The established synchronization scheme of SS-OCT calls for the raster-line frequency to be a remainder-less divider of the sweep frequency. Two methods are presented that increase flexibility in scanner operation.},
}
Simon Lotz, Wolfgang Draxinger, Anneli Dick, and Robert Huber,
Megahertz FDML laser with on-the-fly adjustable sweep rate between 835 kHz and 13.4 MHz, in European Conferences on Biomedical Optics 2025 , Optica Publishing Group, 2025. pp. W5D.4.
DOI:10.1364/ECBO.2025.W5D.4
Datei: abstract.cfm
Bibtex: BibTeX
@inproceedings{Lotz:25,
author = {Simon Lotz and Wolfgang Draxinger and Anneli Dick and Robert Huber},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Fiber Bragg gratings; Imaging techniques; Laser sources; Optical buffers; Swept sources; Three dimensional imaging},
pages = {W5D.4},
publisher = {Optica Publishing Group},
title = {Megahertz FDML laser with on-the-fly adjustable sweep rate between 835 kHz and 13.4 MHz},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-W5D.4},
doi = {10.1364/ECBO.2025.W5D.4},
abstract = {We present a Megahertz FDML laser which can be automatically, and on-the-fly switched to speed values between 830 kHz and 13.4 MHz using optical switches in the buffer stage.},
}
Awanish Pratap Singh, Madita Göb, Sazgar Burhan, Nikolay Tesmer, Wolfgang Draxinger, Simon Lotz, Berenice Schulte, Mark Ellrichmann, Robert Huber, and Maik Rahlves,
Multi-MHz-OCT Endoscopic Imaging with an Automated Pullback Mechanism, in European Conferences on Biomedical Optics 2025 , Optica Publishing Group, 2025. pp. M1C.1.
DOI:10.1364/ECBO.2025.M1C.1
Datei: abstract.cfm
Sazgar Burhan, Madita Göb, Gereon Hüttmann, and Robert Huber,
Non-Equidistant Temporal Scanning in Dynamic MHz-OCT for Higher Speed, in European Conferences on Biomedical Optics 2025 , Optica Publishing Group, 2025. pp. S4B.3.
DOI:10.1364/ECBO.2025.S4B.3
Datei: abstract.cfm
Bibtex: BibTeX
@inproceedings{Burhan:25,
author = {Sazgar Burhan and Madita G\"{o}b and Gereon H\"{u}ttmann and Robert Huber},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Imaging techniques; In vivo imaging; Optical coherence tomography; Optical systems; Spatial resolution; Tissue imaging},
pages = {S4B.3},
publisher = {Optica Publishing Group},
title = {Non-Equidistant Temporal Scanning in Dynamic MHz-OCT for Higher Speed},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-S4B.3},
doi = {10.1364/ECBO.2025.S4B.3},
abstract = {We investigate advanced scanning strategies to improve speed in dynamic MHz-OCT, demonstrating that temporally non-uniform sampling outperforms uniform scanning by achieving faster imaging speeds while largely preserving image clarity.},
}
Tjalfe Laedtke, Sazgar Burhan, Simon Lotz, Madita Göb, and Robert Huber,
Speckle Reduction Through Angular Compounding in Robotically Assisted MHz-OCT, in European Conferences on Biomedical Optics 2025 , Optica Publishing Group, 2025. pp. W1D.4.
DOI:10.1364/ECBO.2025.W1D.4
Datei: abstract.cfm
Bibtex: BibTeX
@inproceedings{Laedtke:25,
author = {Tjalfe Laedtke and Sazgar Burhan and Simon Lotz and Madita G\"{o}b and Robert Huber},
booktitle = {European Conferences on Biomedical Optics 2025},
journal = {European Conferences on Biomedical Optics 2025},
keywords = {Image registration; Imaging systems; Phase shift; Spatial resolution; Speckle noise; Speckle patterns},
pages = {W1D.4},
publisher = {Optica Publishing Group},
title = {Speckle Reduction Through Angular Compounding in Robotically Assisted MHz-OCT},
year = {2025},
url = {https://opg.optica.org/abstract.cfm?URI=ECBO-2025-W1D.4},
doi = {10.1364/ECBO.2025.W1D.4},
abstract = {We demonstrate speckle reduction in robotically assisted MHz-OCT by angular compounding. The robot is used to acquire images from different angles, which, after registration, are used for efficient speckle averaging without loss of spatial resolution.},
}

2024

Noah Heldt, Cornelia Holzhausen, Martin Ahrens, Mario Pieper, Peter König, and Gereon Huettmann,
Reducing dOCT imaging time, in Abstract Book 12th DZL Annual Meeting , Deutsches Zentrum für Lungenforschung e. V Geschäftsstelle Aulweg 130 35392 Gießen: Deutsches Zentrum für Lungenforschung e. V, Jun.2024. pp. 399.
Weblink: https://dzl.de/wp-content/uploads/2024/06/DZL2024_Abstract_Book-1.pdf
Datei: Dateilink
Alexander Altmann, Christian Schell, and Ramtin Rahmanzadeh,
Assessing food degradation and microbial growth by sensor read-out with fluorescence spectroscopy, in Frontiers in Biological Detection: From Nanosensors to Systems XVI , Amos Danielli and Benjamin L. Miller and Sharon M. Weiss, Eds. SPIE, Mä.2024. pp. 128610A.
DOI:10.1117/12.3000908
Bibtex: BibTeX
@inproceedings{10.1117/12.3000908,
author = {Alexander Altmann and Christian Schell and Ramtin Rahmanzadeh},
title = {{Assessing food degradation and microbial growth by sensor read-out with fluorescence spectroscopy}},
volume = {12861},
booktitle = {Frontiers in Biological Detection: From Nanosensors to Systems XVI},
editor = {Amos Danielli and Benjamin L. Miller and Sharon M. Weiss},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {128610A},
abstract = {Both the waste of edible food and the consumption of non-edible food within the best before date are ongoing concerns in food industry. Until now, no methods are applied to access food quality of packed food without opening of packages. We demonstrate the formulation of a sensor foil comprising of a non-toxic porphyrin on an inorganic matrix in polyethylene. The sensor foil is capable of detecting amines in the gas phase over food products, which could act as spoilage indicators during the shelf life of packaged food. The foil was optimized to prevent reactions with other analytes in the gas phase of food by the alteration of the hydrophobic polymer. We performed experiments, using model packing units, to monitor the behavior of the foil and correlated the change in the fluorescence spectra to the total viable count of bacteria on the fish. The readout of the foils was performed with fluorescence spectroscopy to yield highly accurate results in contrast to less accurate the colorimetric determination.},
keywords = {fluorescence spectroscopy, gas sensing, amine sensor, food safety, porphyrins},
year = {2024},
doi = {10.1117/12.3000908},
URL = {https://doi.org/10.1117/12.3000908}
}
Alexander Altmann, Mohammad Khodaygani, Martin Leucker, Christian Schell, and Ramtin Rahmanzadeh,
Detection of spoiled food along the supply chain with novel sensors for packed food, in Photonic Technologies in Plant and Agricultural Science , Dag Heinemann and Gerrit Polder, Eds. SPIE, Mä.2024. pp. 1287906.
DOI:10.1117/12.3000912
Bibtex: BibTeX
@inproceedings{10.1117/12.3000912,
author = {Alexander Altmann and Mohammad Khodaygani and Martin Leucker and Christian Schell and Ramtin Rahmanzadeh},
title = {{Detection of spoiled food along the supply chain with novel sensors for packed food}},
volume = {12879},
booktitle = {Photonic Technologies in Plant and Agricultural Science},
editor = {Dag Heinemann and Gerrit Polder},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1287906},
abstract = {Along food supply chains, several critical steps can lead to inconsumable food. Especially food of animal origin undergoes rapid aging, when stored inadequately. Quality assessment of packaged food products faces serious problems ranging from the loss of integrity of the package to damage of the food and it is applied only to a low number of samples per batch. As a result, food products are either wasted or not analyzed, which results in a significant decrease in food safety. As a part of an intelligent packaging system, we designed a sensor foil that can detect amines, produced during the food aging process. Change of the fluorescence of the sensor foil can be assessed with spectroscopy or color change from green to red can be detected optically with a camera, e.g. by smartphone. The foil can be incorporated inside the single packaging units and noninvasively measured routinely by the store or consumer. The readout of the foils was performed with steady-state tabletop spectrometers, which were then compared to the results for readouts with different inexpensive handheld devices that could be used during real-life applications, e.g., at any step in a food supply chain.  Ideally, the single food product is linked to a single foil at the primary producer, measuring the first spectrum and connecting the data to the specific product, e.g. via distributed ledger. For a transparent process chain, QR-codes could be utilized to allow access to the freshness data along the shelf life of a single package. },
keywords = {fluorescence spectroscopy, gas sensing, amine sensor, food safety, porphyrins, SVM classifier, block chain, non-destructive food testing},
year = {2024},
doi = {10.1117/12.3000912},
URL = {https://doi.org/10.1117/12.3000912}
}
Noah Heldt, Cornelia Holzhausen, Martin Ahrens, Mario Pieper, Peter König, and Gereon Hüttmann,
Improved image quality in dynamic OCT imaging by reduced imaging time and machine learning based data evaluation, in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVIII , Joseph A. Izatt and James G. Fujimoto, Eds. SPIE, 2024. pp. PC128302A.
DOI:10.1117/12.3005413
Weblink: https://www.spiedigitallibrary.org/conference-proceedings-of-spie/PC12830/PC128302A/Improved-image-quality-in-dynamic-OCT-imaging-by-reduced-imaging/10.1117/12.3005413.full
Bibtex: BibTeX
@inproceedings{10.1117/12.3005413,
author = {Noah Heldt and Cornelia Holzhausen and Martin Ahrens and Mario Pieper and Peter K{\"o}nig and Gereon H{\"u}ttmann},
title = {{Improved image quality in dynamic OCT imaging by reduced imaging time and machine learning based data evaluation}},
volume = {PC12830},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVIII},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {PC128302A},
abstract = {Dynamic Optical Coherence Tomography combines high resolution tomographic imagery with a cell specific contrast by Fourier analysis. However, the conversion from frequency space into RGB images by binning requires a priori knowledge and artifacts due to global movements provide another obstacle for in vivo application.
We could show that an automated binning based on the Neural Gas algorithm can yield the highest spectral contrast without a priori knowledge and that motion artifacts can be reduced with shorter sequence lengths. Imaging murine airways, we observed that even just 6 frames are enough to generate dOCT images without losing important image information.},
keywords = {Dynamic OCT, Optical Coherence Tomography, Airways, Artificial Intelligence},
year = {2024},
doi = {10.1117/12.3005413},
URL = {https://doi.org/10.1117/12.3005413}
}
Gereon Hüttmann,
Mathematical model for separating signal and noise in dynamic optical coherence tomography (dOCT), in Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVIII , Joseph A. Izatt and James G. Fujimoto, Eds. SPIE, 2024. pp. PC1283029.
DOI:10.1117/12.3005716
Weblink: https://www.spiedigitallibrary.org/conference-proceedings-of-spie/PC12830/PC1283029/Mathematical-model-for-separating-signal-and-noise-in-dynamic-optical/10.1117/12.3005716.short
Bibtex: BibTeX
@inproceedings{10.1117/12.3005716,
author = {Gereon Hüttmann},
title = {Mathematical model for separating signal and noise in dynamic optical coherence tomography (dOCT)},
volume = {PC12830},
booktitle = {Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXVIII},
editor = {Joseph A. Izatt and James G. Fujimoto},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {PC1283029},
abstract = {Dynamic optical coherence tomography (dOCT) uses signal fluctuation for contrasting different cellular and acellular components in living biological tissue. The autocorrelation or Fourier transform of time series of OCT measurements are converted to a color contrast. However, a quantitative analysis is still challenging. Here we investigate theoretically, how noise of the OCT measurement influences the fluctuation spectra. Probability functions are derived for the different components in the spectra and validated by numerical simulation. With an appropriate calibration of the OCT device a separation of OCT noise and a quantification the dynamic OCT should be feasible.},
keywords = {Optical coherence tomography (OCT), Dynamic optical coherence tomography (OCT), Signal to noise, Speckle statistics, Quantification},
year = {2024},
doi = {10.1117/12.3005716},
URL = {https://doi.org/10.1117/12.3005716}
}

2023

Sazgar Burhan, Nicolas Detrez, Madita Göb, Matteo Mario Bonsanto, Ralf Brinkmann, and Robert Huber,
Advanced FFT-based contrast approach for MHz optical coherence elastography, in Optical Coherence Imaging Techniques and Imaging in Scattering Media V , Benjamin J. Vakoc and Maciej Wojtkowski and Yoshiaki Yasuno, Eds. SPIE, Aug.2023. pp. 1263215.
DOI:10.1117/12.2670957
Bibtex: BibTeX
@inproceedings{10.1117/12.2670957,
author = {Sazgar Burhan and Nicolas Detrez and Madita G{\"o}b and Matteo Mario Bonsanto and Ralf Brinkmann and Robert Huber},
title = {{Advanced FFT-based contrast approach for MHz optical coherence elastography}},
volume = {12632},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media V},
editor = {Benjamin J. Vakoc and Maciej Wojtkowski and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {1263215},
abstract = {Optical coherence elastography represents mechanical characteristics of biological tissue in so-called mechanical contrast maps. In addition to the standard intensity image, the contrast map illustrates numerous mechanical tissue features that would otherwise be undetectable. This is of great interest as abnormal physiological changes influence the mechanical behavior of the tissue. We demonstrate an advanced mechanical contrast approach based on the phase signal of our 3.2 MHz optical coherence tomography system. The robustness and performance of this contrast approach is evaluated and discussed based on preliminary results. },
keywords = {Optical Coherence Tomography, OCT, Megahertz OCT, Fourier Domain Mode Locking, Optical Coherence Elastography, OCE, Phase-sensitive OCT, Biomechanics},
year = {2023},
doi = {10.1117/12.2670957},
URL = {https://doi.org/10.1117/12.2670957}
}
Madita Göb, Simon Lotz, Linh Ha-Wissel, Sazgar Burhan, Sven Böttger, Floris Ernst, Jennifer Hundt, and Robert Huber,
Advances in large area robotically assisted OCT (LARA-OCT): towards drive-by continuous motion imaging, in Optical Coherence Imaging Techniques and Imaging in Scattering Media V , Benjamin J. Vakoc and Maciej Wojtkowski and Yoshiaki Yasuno, Eds. SPIE, Aug.2023. pp. 126321N.
DOI:10.1117/12.2670950
Bibtex: BibTeX
@inproceedings{10.1117/12.2670950,
author = {Madita G{\"o}b and Simon Lotz and Linh Ha-Wissel and Sazgar Burhan and Sven B{\"o}ttger and Floris Ernst and Jennifer Hundt and Robert Huber},
title = {{Advances in large area robotically assisted OCT (LARA-OCT): towards drive-by continuous motion imaging}},
volume = {12632},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media V},
editor = {Benjamin J. Vakoc and Maciej Wojtkowski and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {126321N},
abstract = {Optical coherence tomography is a powerful imaging technique to visualize and localize depth-dependent tissue structure to differentiate between healthy and pathological conditions. However, conventional OCT systems are only capable of detecting small areas. To overcome this limitation, we have developed a large area robotically assisted OCT (LARA-OCT) system for automatic acquisition of large OCT images. Using mosaic pattern acquisition and subsequent stitching, we previously demonstrated initial in vivo OCT skin images beyond 10 cm². To improve acquisition speed and reduce dead times, we here demonstrate and analyze LARA-OCT with a new drive-by continuous motion imaging protocol.},
keywords = {Optical Coherence Tomography, Fourier Domain Mode Locking, Robotically Assisted Imaging Systems, Three-dimensional image acquisition, Large Area Scanning, Skin Imaging, OCT, FDML},
year = {2023},
doi = {10.1117/12.2670950},
URL = {https://doi.org/10.1117/12.2670950}
}
Paul Strenge, Birgit Lange, Wolfgang Draxinger, Christian Hagel, Christin Grill, Veit Danicke, Dirk Theisen-Kunde, Sonja Spahr-Hess, Matteo M. Bonsanto, Robert Huber, Heinz Handels, and Ralf Brinkmann,
Demarcation of brain and tumor tissue with optical coherence tomography using prior neural networks}, in Optical Coherence Imaging Techniques and Imaging in Scattering Media V , Benjamin J. Vakoc and Maciej Wojtkowski and Yoshiaki Yasuno, Eds. SPIE, Aug.2023. pp. 126321P.
DOI:10.1117/12.2670907
Datei: 12.2670907
Bibtex: BibTeX
@inproceedings{10.1117/12.2670907,
author = {Paul Strenge and Birgit Lange and Wolfgang Draxinger and Christian Hagel and Christin Grill and Veit Danicke and Dirk Theisen-Kunde and Sonja Spahr-Hess and Matteo M. Bonsanto and Robert Huber and Heinz Handels and Ralf Brinkmann},
title = {{Demarcation of brain and tumor tissue with optical coherence tomography using prior neural networks}},
volume = {12632},
booktitle = {Optical Coherence Imaging Techniques and Imaging in Scattering Media V},
editor = {Benjamin J. Vakoc and Maciej Wojtkowski and Yoshiaki Yasuno},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {126321P},
keywords = {Brain Tumor, OCT, Optical Coherence Tomography, Prior Network, Glioblastoma Multiforme, Neural Network, Classification},
year = {2023},
doi = {10.1117/12.2670907},
URL = {https://doi.org/10.1117/12.2670907}
}
Wolfgang Draxinger, Dirk Theisen-Kunde, Lion Schuetz, Nicolas Detrez, Paul Strenge, Maximilian Rixius, Veit Danicke, Wolfgang Wieser, Jessica Kren, Patrick Kuppler, Sonja Spar-Hess, Matteo M. Bonsanto, Ralf Brinkmann, and Robert Huber,
Microscope integrated realtime high density 4D MHz-OCT in neurosurgery: a depth and tissue resolving visual contrast channel and the challenge of fused presentation, in Translational Biophotonics: Diagnostics and Therapeutics III , Zhiwei Huang and Lothar D. Lilge, Eds. SPIE, Aug.2023. pp. 126270W.
DOI:10.1117/12.2670953
Bibtex: BibTeX
@inproceedings{10.1117/12.2670953,
author = {Wolfgang Draxinger and Dirk Theisen-Kunde and Lion Schuetz and Nicolas Detrez and Paul Strenge and Maximilian Rixius and Veit Danicke and Wolfgang Wieser and Jessica Kren and Patrick Kuppler and Sonja Spar-Hess and Matteo Mario Bonsanto M.D. and Ralf Brinkmann and Robert Huber},
title = {{Microscope integrated realtime high density 4D MHz-OCT in neurosurgery: a depth and tissue resolving visual contrast channel and the challenge of fused presentation}},
volume = {12627},
booktitle = {Translational Biophotonics: Diagnostics and Therapeutics III},
editor = {Zhiwei Huang and Lothar D. Lilge},
organization = {International Society for Optics and Photonics},
publisher = {SPIE},
pages = {126270W},
abstract = {Microscope integrated realtime 4D MHz-OCT operating at high scanning densities are capable of capturing additional visual contrast resolving depth and tissue. Even within a plain C-scan en-face projection structures are recognizable, that are not visible in a white light camera image. With advanced post processing methods, such as absorbtion coefficient mapping, and morphological classifiers more information is extraced. Presentation to the user in an intuitive way poses practical challenges that go beyond the implementation of a mere overlay display. We present our microscope integrated high speed 4D OCT imaging system, its clinical study use for in-vivo brain tissue imaging, and user feedback on the presentation methods we developed.},
keywords = {optical coherence tomography, neurosurgery, tissue contrast, image fusion, surgical guidance, theranostics},
year = {2023},
doi = {10.1117/12.2670953},
URL = {https://doi.org/10.1117/12.2670953}
}