TY  - JOUR
A1  - Bräuer-Burchardt, Christian
A1  - Munkelt, Christoph
A1  - Bleier, Michael
A1  - Heinze, Matthias
A1  - Gebhart, Ingo
A1  - Kühmstedt, Peter
A1  - Notni, Gunther
T1  - A new sensor system for accurate 3D surface measurements and modeling of underwater objects
JF  - Applied Sciences
N2  - A new underwater 3D scanning device based on structured illumination and designed for continuous capture of object data in motion for deep sea inspection applications is introduced. The sensor permanently captures 3D data of the inspected surface and generates a 3D surface model in real time. Sensor velocities up to 0.7 m/s are directly compensated while capturing camera images for the 3D reconstruction pipeline. The accuracy results of static measurements of special specimens in a water basin with clear water show the high accuracy potential of the scanner in the sub-millimeter range. Measurement examples with a moving sensor show the significance of the proposed motion compensation and the ability to generate a 3D model by merging individual scans. Future application tests in offshore environments will show the practical potential of the sensor for the desired inspection tasks.
KW  - optical underwater 3D sensor
KW  - structured illumination
KW  - motion compensation
KW  - 3D model generation
KW  - high-accuracy 3D measurements
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-270792
SN  - 2076-3417
VL  - 12
IS  - 9
ER  - 
TY  - JOUR
A1  - Wäldchen, Sina
A1  - Lehmann, Julian
A1  - Klein, Teresa
A1  - van de Linde, Sebastian
A1  - Sauer, Markus
T1  - Light-induced cell damage in live-cell super-resolution microscopy
JF  - Scientific Reports
N2  - Super-resolution microscopy can unravel previously hidden details of cellular structures but requires high irradiation intensities to use the limited photon budget efficiently. Such high photon densities are likely to induce cellular damage in live-cell experiments. We applied single-molecule localization microscopy conditions and tested the influence of irradiation intensity, illumination-mode, wavelength, light-dose, temperature and fluorescence labeling on the survival probability of different cell lines 20-24 hours after irradiation. In addition, we measured the microtubule growth speed after irradiation. The photo-sensitivity is dramatically increased at lower irradiation wavelength. We observed fixation, plasma membrane permeabilization and cytoskeleton destruction upon irradiation with shorter wavelengths. While cells stand light intensities of similar to 1 kW cm\(^{-2}\) at 640 nm for several minutes, the maximum dose at 405 nm is only similar to 50 J cm\(^{-2}\), emphasizing red fluorophores for live-cell localization microscopy. We also present strategies to minimize phototoxic factors and maximize the cells ability to cope with higher irradiation intensities.
KW  - optical reconstruction microscopy
KW  - tag fusion proteins
KW  - localization microscopy
KW  - photodynamic therapy
KW  - diffraction limit
KW  - illumination microscopy
KW  - structured illumination
KW  - fluorescent probes
KW  - in vitro
KW  - dynamics
Y1  - 2015
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-145207
VL  - 5
IS  - 15348
ER  -