A5034111121- Random lasers and scattering media
- Optical Coherence Tomography Applications
- Digital Holography and Microscopy
- Advanced Optical Imaging Technologies
- Near-Field Optical Microscopy
- Orbital Angular Momentum in Optics
- Surgical Simulation and Training
- Optical Coatings and Gratings
- Photoacoustic and Ultrasonic Imaging
- Optical Wireless Communication Technologies
- Meteorological Phenomena and Simulations
- Dermatologic Treatments and Research
- Augmented Reality Applications
- Ocean Waves and Remote Sensing
- Microfluidic and Bio-sensing Technologies
- Public Administration and Political Analysis
- Law and Political Science
- Electromagnetic Simulation and Numerical Methods
- Digital Imaging in Medicine
- Ocular Surface and Contact Lens
- Laser Material Processing Techniques
- Surface Roughness and Optical Measurements
- Medical and Health Sciences Research
- Electromagnetic Scattering and Analysis
- History and Developments in Astronomy
Technische Universität Dresden
2018-2025
Deutsche Telekom (Austria)
2022
Minimally invasive endoscopes are indispensable in biomedicine. Coherent fiber bundles (CFBs) enable ultrathin lensless endoscopes. However, the propagation of light through a CFB suffers from phase distortions and aberrations that can cause images to be scrambled. The correction such has been demonstrated using various techniques for wavefront control, especially spatial modulators (SLMs). This study investigates novel aberration without SLM creation an efficient compact system. memory...
Coherent fiber bundle (CFB)-based endoscopes enable optical keyhole access in applications such as biophotonics. In conjunction with objective lenses, CFBs allow imaging of intensity patterns. contrast, digital phase conjugation enables lensless holographic for the generation pixelation-free arbitrary light For real-world applications, however, this requires a non-invasive situ calibration complex transfer function CFB only single-sided access. We show that after an initial forward...
Lensless fiber endoscopes are of great importance for keyhole imaging. Coherent bundles (CFB) can be used in as remote phased arrays to capture images. One challenge is image at high speed while correcting aberrations induced by the CFB. We propose combination digital optical phase conjugation, using a spatial light modulator, with fast scanning, which 2D galvo scanner and an adaptive lens employed. achieve transmission laser scanning through Video-rate imaging 20 Hz subcellular resolution...
Abstract Fiber‐based endoscopy holds unique and breakthrough potential for translating conventional microscopy to minimally invasive applications. An outstanding example is in vivo all‐optical cancer diagnostics, which mitigates patient safety risks economic costs of surgical tissue extraction. Recently, lensless has enabled 3D illumination imaging through specialty fibers with diameters only a few hundred microns. However, it requires complex electro‐optical components sophisticated...
Abstract Endoscopes enable optical keyhole access in many applications for instance biomedicine. In general, coherent fiber bundles (CFB) are used conjunction with rigid lens systems which determine a fixed image plane. However, the system limits minimum diameter of endoscope typically to several millimeters. Additionally, only pixelated two-dimensional amplitude patterns can be transferred due phase scrambling between adjacent cores. These limitations overcome by digital elements. Thus,...
Fiber bundles are used in endoscopy for pixelated image transfer. Due to scattering of the effective refractive index, phase information is lost, however. Digital optical conjugation has been reverse this effect partially, which enables endoscopes without distal optics and diffraction-limited 3D capability. However, imaging limited a single wavelength. We demonstrate multispectral broadband using spatial light modulators with shift exceeding 2pi. Imaging can be achieved by correcting...
Multi-core optical fibers are widely used for information transfer and endoscopy. However, dispersion effects result in phase noise of the transmitted light fields, limiting applications. This can be characterized holographically. We investigate use laser ablation to apply holograms correcting noise. show that desired correction applied via intensity modulation. compare shift single-shot vs multi-shot ablation. Additionally, is compared additive manufacturing digital conjugation. The...
Lens-less endoscopy based on multi-core fibers (MCFs) with aperiodic core arrangements enables 3D imaging deep inside tissue reduced artifacts such as higher-order diffraction. With a scalable iterative stack-and-draw process, we fabricated and characterized (e.g. cross-talk) two MCFs: (i) 250 µm fiber 420 cores (ii) 333 1281 cores. Since lens-less is sensitive to dynamic bending, different approaches twist the were evaluated: i) rotation of preform during drawing post-production twisting...
We present a holographic endoscope with tiny footprint. A novel non-invasive in situ calibration of coherent fiber bundle combination galvanometer scanner enables fast, minimally invasive 3D measurements.
Zusammenfassung Endoskope sind für die minimalinvasive Chirurgie essenziell. Dabei ist vor allem ein hohes Auflösungsvermögen bei geringem Durchmesser gefordert. Kommerzielle auf Faserbündel basierte Verfahren verwenden aufgrund der gestörten Phaseninformation lediglich Intensitätsinformation und erreichen so eine maximale Auflösung von 10 kpx einem Endoskopdurchmesser im mm-Bereich. Hier wird neuartiges vorgestellt, welches durch empfangsseitige Kompensation Phasenstörung ≈ 69 gleichzeitig...
Holographic endoscopes with sub-millimeter diameter require the compensation of inter-core phase distortions, which is accomplished often an SLM. We present use 3D printed DOE as a robust integrative technique for biomedicine.
Coherent fiber bundles used in endoscopic imaging suffer from inter-core dispersion resulting pseudo random phase distortions for a transmitted wavefront. This limits their application to relaying intensity patterns pixelated, 2D near field imaging. In the last years, employing spatial light modulators digital optical conjugation of these and unpixellated 3D raster scanning has been demonstrated. Here we present using 2-Photon Polymerization writing compensation holograms onto CFB facet...
Multicore fibers (MCF) have potential for use in endoscopy due to their flexibility and small diameters. We found that 2-Photon Polymerization (2PP) can be used phase correction, enabling cost-effective robust lensless endoscopes clinics.
Endoscopy is a key technology in biomedical engineering. It enables minimal invasive optical access deep into tissue. State of the art to use coherent fiber bundles (CFB) conjunction with rigid lens systems. Thus, structures can be detected fixed distance probe tip. However, system limits minimum diameter endoscope several millimeters. Through imperfections, core-to-core crosstalk and bending sensitivity only intensity evaluated, phase information light gets lost. By compensation distortion...
We present an ultrathin fiber endoscope with digital optical phase conjugation and novel self-calibration. Minimally invasive 3D imaging stimulation subcellular resolution is provided for biomedical applications such as optogenetics.
tm -Technisches MessenPlattform für Methoden, Systeme und Anwendungen in der Messtechnik.Organ des AHMT (Arbeitskreis Hochschullehrer Messtechnik e.V.), AMA (Verband Sensorik e.V.) NAMUR (
We present a fast holographic endoscope with needle footprint. Robustness versus bending is achieved by single sided self-calibration of the fiber bundle. Incorporating an adaptive lens and 2-axis galvo scanner allows 3D scans one Mega voxel per second. While imaging demonstrated at 3µm fluorescent beads, we also demonstrate applicability in cell rotators precisely rotating two foci angle uncertainty below 1°. For future, expect this approach will lead us to create tools for deeper tissue...
Minimally invasive optical systems allow to access deep tissue regions living organisms, for instance microscopy or cell manipulation. Multi core fibers (CFB) are predestined advancing needle-size microendoscopy, since they offer several 10,000 independent channels with a total outer diameter down 0.2 mm. The applicability of CFBs as means undisturbed light transfer in is limited however, random, unknown and time dependent phase distortions occurs between individual cores. This distortion...
Coherent Fiber Bundels (CFB) enable ultrathin lensless endoscopes, but suffer from phase distortions. Currently spatial light modulators are used for conjugation enabling 3D imaging, without distal optics. We introduce diffractive optical elements (DOE) aberration correction. DOEs made by 2-photon lithography to correct static distortions and direct transfer of holograms imaging. Furthermore, random can code object information in 2D intensity speckle patterns, which decoded using neural...
Investigation of
This paper presents a paradigm shift in endoscopy using coherent fiber bundles (CFB). The memory effect of CFB is exploited towards 3D printed diffractive optical elements (DOE) and deep neural networks.
Recently, 3D imaging endoscopes have made their way into endoscopy and enable three-dimensional visualization. While many of them require optics with mounts increasing the fibers diameter, two-photon polymerization enables mount-free fabrication optical elements directly on tip fibers. Using multicore combined diffractive (DOE) phase to be taken account in measurements addition intensity, enabling imaging. each fiber has an individual distribution differences, DOE is required, which can...