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Gurthwin Bosman

Publications and source records attributed to Gurthwin Bosman.

2 recordsLinked to original sources

Calculating Point Spread Functions: Methods, Pitfalls and Solutions

The knowledge of the exact structure of the optical system PSF enables a high-quality image reconstruction in fluorescence microscopy. Accurate PSF models account for the vector nature of light and the phase and amplitude modifications. Most existing real-space-based PSF models fall into a sampling pitfall near the centre position, yielding to the violation of the energy conservation. In this work, we present novel, to the best of our knowledge, Fourier-based techniques for computing vector PSF and compare them to the state-of-the-art. Our methods are shown to satisfy the physical condition of the imaging process. They are reproducible, computationally efficient, and easy to implement and easy to modify to represent various imaging modalities.

physics.optics

Generalized spectral phase-only time-domain ptychographic phase reconstruction applied in nonlinear microscopy

Nonlinear microscopy has evolved over the last few decades to become a powerful tool for imaging and spectroscopic applications in biological sciences. In this study, I$^2$PIE, a novel spectral phase control technique, was implemented in order to compress broad-bandwidth supercontinuum light pulses generated in an all-normal-dispersion (ANDi) photonic crystal fiber (PCF). The technique, based on time-domain ptychography, is demonstrated here in a nonlinear microscopy application for the first time, to the best of our knowledge. The first real-world application of this technique for second-harmonic generation and two-photon excitation fluorescence microscopies in biological samples is presented. We further show that in our implementation, I$^2$PIE leads to improved contrast and signal-to-noise ratios in the generated images, compared to conventional compression techniques used in nonlinear microscopy.

physics.optics