Sub-surface fluorescence time-of-flight imaging using a large format SPAD sensor

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The measurement of tissue and cell oxygenation is important for understanding cell metabolism. We have addressed this problem with a novel optical technique, called triplet imaging, that exploits oxygen-induced triplet lifetime changes and is compatible with a variety of fluorophores. A modulated excitation of varying pulse widths allows the extraction of the lifetime of the essentially dark triplet state using a high-fluorescence signal intensity. This enables the monitoring of fast kinetics of oxygen conc

We present a dynamic laser beam shaper based on MEMS technology. We show a prototype of a dynamic diffuser made of single crystal silicon. A linearly deformable silicon micromembrane is used to diffuse a laser beam in one dimension. Resonance frequencies of the membrane can range from 1 kHz to 20 kHz. Mode shapes of the deformable mirror are excited using magnetic actuation. Diffusing angle can be tuned by adjusting the driving current in the membrane. We measured a diffusing angle of 1 degrees for an appli

Immense amounts of high resolution data are now routinely produced thanks to recent advances in EM imaging. While a strong demand for automated analysis now exists, it is stifled by the lack of robust automatic 3D segmentation techniques. State-of-the-art Computer Vision algorithms designed to operate on natural 2D images tend to perform poorly when applied to EM image stacks for a number of reasons. The sheer size of a typical EM image stack renders many segmentation schemes intractable. Most approaches re

Different inks may have different mechanical and/or optical properties. Existing Yule-Nielsen modified Neugebauer spectral prediction models assume however that the inks forming a color halftone behave similarly, i.e. that a single n-factor can model the lateral propagation of light within the paper as well as non-uniformities of the ink dot thickness profiles. However, if the inks have very different optical or mechanical properties, each ink may be separately modeled with its specific n-factor. In order t

This reports documents qualification tests made with the 100Ω PTC resistive composition DuPont (DP) 5092D, co-fired on the surface and inside (buried) DP 951 LTCC material, using a wide range of Ag & alloyed Ag-Pd conductor termination: DP 6142D & 6145 (Ag), and 6135D & 6143 & 6146 & 7484 (Ag-Pd). These tests were deemed necessary, as previous ones [1], carried out with Ag terminations only, were deemed not conclusive and reliable enough. The resulting resistors were electrically characterised, and the reli

This paper presents Digital Holographic Microscopy (DHM) quantitative measurements of transparent high aspect-ratio microstructures. Our experiment was performed using a digital holographic microscope in transmission configuration with a 60x magnification 1.3 NA oil immersion microscope objective, with a diode laser source at 664 nm. We used a calculation model based on the use of two immersion liquids for the experiment, the first one to resolve the phase jumps by using a refractive index liquid close to t

3D shape acquisition has become a major tool for creating digital 3D surface data in a variety of application elds. Despite the steady increase in accuracy, most available scanning techniques cause severe scanning artifacts such as noise, outliers, holes, or ghost geometry. To apply sophisticated modeling operations on these data sets, substantial post-processing is usually required. In this paper, we address a variety of scanning artifacts that are created by common optical scanners and provide a comprehen

The present invention provides methods and apparatus for locally patterning surfaces. In one such method, an oxidizable thioether is adsorbed onto a conductive surface 10. The surface is then contacted with a fluid medium M. A conducting stamp 12 is then brought into contact with the fluid medium above the thioether-coated surface. Next, a potential V is applied between the stamp and the surface. It is expected that the charge will be transferred through the medium to the coated surface along a shortest dis

Accurate detn. of the transient electronic structures, which drive photochem. reactions, is crucial in chem. and biol. The authors report the detection of transient chem. changes on the picosecond time scale by x-ray-absorption near-edge structure of photoexcited aq. [Ru(bpy)3]2+. Upon ultrashort laser pulse excitation a charge transfer excited state having a 300 ns lifetime is formed. The authors detect the change of oxidn. state of the central Ru atom at its L3 and L2 edges, at a temporal resoln. of 100 p

We describe a microwave-optical double resonance experiment designed for Stark effect measurements on molecules in excited vibrational energy levels of ground electronic states. This technique, which employs pulsed laser excitation and laser induced fluorescence detection, has been used to measure electric dipole moments in the 1(1), 5(1), and 5(2) vibrational states of formaldehyde. In addition, a Stark induced quantum beat experiment is briefly described. (C) 2003 American Institute of Physics.

Fluorescent protein expressing cells with very high fluorescence are described as well as a method to obtain such cells. The fluorescence of such cells can be as high as about 1000 times the auto-fluorescence of the respective host cell. Due to the high fluorescence, said cells are very suitable tools in the development, surveillance and/or optimization of production processes, for selection of culture media and process parameters and for the determination of cell growth and the detection, quantification an

We report rotationally resolved spectra of jet-cooled methanol for the OH stretch overtones, 2v(1) and 3v(1), and for the torsional combinations, 2v(1)+v(12), 2v(1)+2v(12), 3v(1)+v(12), and 3v(1)+2v(12). The spectra are obtained by direct excitation from the vibrational ground state with an infrared laser pulse. Population in the resulting upper state levels is detected by infrared laser assisted photofragment spectroscopy (IRLAPS). Global fits of the spectra to the Herbst Hamiltonian yield the torsional an

Sub-surface fluorescence time-of-flight imaging using a large format SPAD sensor

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Triplet imaging of oxygen consumption during the contraction of a single smooth muscle cell (A7r5)

Deformable Silicon Membrane for Dynamic Linear Laser Beam Diffuser

Supervoxel-Based Segmentation of EM Image Stacks with Learned Shape Features

Ink-dependent n-factors for the Yule-Nielsen modified spectral Neugebauer model

Buried & surface cofiring compatibility of DuPont 5092D PTC thermistor composition with DuPont 951 LTCC

Measurements of corner cubes microstructures by high-magnification digital holographic microscopy

Post-processing of scanned 3D surface data

Methods and apparatus for patterning a surface

Observing Photochemical Transients by Ultrafast X-Ray Absorption Spectroscopy

Fluorescence detected microwave Stark effect measurements in excited vibrational states of H2CO

Cells, genetically modified with optical marker

Torsion-rotation analysis of OH stretch overtone-torsion combination bands in methanol