title: Enhanced resolution in two-photon imaging using a TM(01) laser beam at a dielectric interface.
abstract: We have experimentally demonstrated that the resolution of a commercial two-photon microscope is improved using a TM(01) laser beam. With a water immersion objective having a 1.2 NA, the measured point- spread function has an area of 0.15lambda(2). We used a plane interface between dielectrics instead of an annular aperture to increase the relative contribution of the longitudinal field of the TM(01) laser beam. The results are in agreement with the vectorial diffraction theory established by Richards and Wolf [Proc. R. Soc. Lond. A253, 358 (1959)]. The TM(01) laser beam was produced with a quadrant of half-wave plates. We have also used the same mode converter to generate a TE(01) laser beam with a zero at the beam center.
authors: Centre d'Optique Photonique et Laser, Université Laval, 2375 de la Terrasse, Québec, Québec G1V 0A6, Canada. harold.dehez.1@ulaval.ca
authors: Harold
authors: H
authors: Dehez
authors: Michel
authors: M
authors: Piché
authors: Yves
authors: Y
authors: De Koninck
mesh_terms: D000388:Air; D017097:Electric Impedance; D005898:Glass; D007834:Lasers; D008962:Models, Theoretical; D057054:Molecular Imaging; D017785:Photons