title: Structure sensitivity in third-harmonic generation microscopy.
abstract: We characterize experimentally the influence of sample structure and beam focusing on signal level in third-harmonic generation (THG) microscopy. In the case of a homogeneous spherical sample, the dependence of the signal on the size of the sphere can be controlled by modifying the Rayleigh length of the excitation beam. More generally, the influence of excitation focusing on the signal depends on sample geometry, allowing one to highlight certain structures within a complex system. We illustrate this point by focusing-based contrast modulation in THG images of Drosophila embryos.
authors.affiliation: Laboratory for Optics and Biosciences, Centre National de la Recherche Scientifique, Ecole Polytechnique, 91128 Palaiseau, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Débarre
authors.forename: Willy
authors.initials: W
authors.lastname: Supatto
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Beaurepaire
mesh_terms: D000818:Animals; D004330:Drosophila / Q000166:cytology* / Q000196:embryology*; D004625:Embryo, Nonmammalian; D007089:Image Enhancement / Q000379:methods*; D008853:Microscopy / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000379:methods*