Frequency dependent detection in a STED microscope using modulated excitation light

Parallel Imaging with RASER using Multiband Frequency-modulated Excitation Pulses

Introduction: The recently described RASER sequence is a conceptual novelty in MR imaging [1]. Based on frequency-swept excitation, and timeencoding, RASER is a rapid, pure T2-weighted scheme without signal voids, ghosting and distortion artifacts present in conventional echo-planar imaging (EPI). These properties render it attractive for functional imaging (fMRI). However, in the previous impl...

Two-Photon Excitation STED Microscopy with Time-Gated Detection

We report on a novel two-photon excitation stimulated emission depletion (2PE-STED) microscope based on time-gated detection. The time-gated detection allows for the effective silencing of the fluorophores using moderate stimulated emission beam intensity. This opens the possibility of implementing an efficient 2PE-STED microscope with a stimulated emission beam running in a continuous-wave. Th...

Two-photon excitation STED microscopy.

We report sub-diffraction resolution in two-photon excitation (TPE) fluorescence microscopy achieved by merging this technique with stimulated-emission depletion (STED). We demonstrate an easy-to-implement and promising laser combination based on a short-pulse laser source for two-photon excitation and a continuous-wave (CW) laser source for resolution enhancement. Images of fluorescent nanopar...

Frequency-mixing detection (FMD) of polarization-modulated light

STED microscope with Spiral Phase Contrast

Stimulated Emission Depletion (STED) microscopy enables superresolution imaging of fluorescently marked nano-structures in vivo. Biological investigations are often hindered by the difficulty of relating super-resolved structures to other non-labeled features. Here we demonstrate that the similarity in optical design of Spiral Phase Contrast (SPC) and STED microscopes allows straightforward imp...