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Tiemo Anhut

Publications and source records attributed to Tiemo Anhut.

4 recordsLinked to original sources

Time-resolved Hadamard fluorescence imaging.

We present a new concept for fluorescence lifetime imaging (FLIM) based on time-resolved Hadamard imaging (HI). HI allows image acquisition by use of one single-point detector without requiring a moving scanning stage. Moreover, it reduces the influence of detector noise compared with raster scanning. By use of Monte Carlo simulations it could be confirmed that Hadamard transformation may decrease the error in lifetime estimation and in general in fluorescence parameter estimation when the signal-to-noise ratio is low and detector dark noise is high. This concept may find applications whenever the performance of FLIM or similar methods is limited by high dark-count rates and when the use of a single-point detector is preferable.

Algorithms↗

Optical sectioning in wide-field microscopy obtained by dynamic structured light illumination and detection based on a smart pixel detector array.

Optical sectioning in wide-field microscopy is achieved by illumination of the object with a continuously moving single-spatial-frequency pattern and detecting the image with a smart pixel detector array. This detector performs an on-chip electronic signal processing that extracts the optically sectioned image. The optically sectioned image is directly observed in real time without any additional postprocessing.

Journal Article↗

Parallel single molecule detection with a fully integrated single-photon 2x2 CMOS detector array.

We present parallel single molecule detection (SMD) and fluorescence correlation spectroscopy (FCS) experiments with a fully integrated complementary metal oxide semiconductor (CMOS) single-photon 2x2 detector array. Multifocal excitation is achieved with a diffractive optical element (DOE). Special emphasis is placed on parallelization of the total system. The performance of the novel single-photon CMOS detector is investigated and compared to a state-of-the-art single-photon detecting module [having an actively quenched avalanche photodiode (APD)] by measurements on free diffusing molecules at different concentrations. Despite the order of magnitude lower detection efficiency of the CMOS detector compared to the state-of-the-art single-photon detecting module, we achieve single molecule sensitivity and reliably determine molecule concentrations. In addition, the CMOS detector performance for the determination of the fraction of slowly diffusing molecules in a primer solution (two-component analysis) is demonstrated. The potential of this new technique for high-throughput confocal-detection-based systems is discussed.

Biopolymers↗