Figure 2
From: Third harmonic imaging contrast from tubular structures in the presence of index discontinuity
THG contrast from stretched glass pipettes in different immersion media. (a) Experimental setup. A stretched glass pipette is filled with a fluorescent inner liquid (\(L_{in}\)), sealed, and placed in a closed observation chamber filled with a second liquid (\(L_{out}\)). \(L_{in}\) and \(L_{out}\) can be either water or a TDE solution index-matched to the pipette. THG signals are detected in transmission. (b) XZ reprojections of 3D images taken near the pipettes tips for different combinations of \(L_{in}\) and \(L_{out}\). Blue: THG signals. Red: fluorescence signals. The plot shows THG and 2PEF intensity profiles in the pipette equatorial plane for the TDE/TDE case. Scale bar: \(10 \mu m\). (c) Relative visibility of the horizontal (H) and vertical (V) interfaces for all experimental conditions.
