title: Quasi-Bessel beams from asymmetric and astigmatic illumination sources.
abstract: We study the spatial intensity distribution and the self-reconstruction of quasi-Bessel beams produced from refractive axicon lenses with edge emitting laser diodes as asymmetric and astigmatic illumination sources. Comparing these to a symmetric mono-mode fiber source, we find that the asymmetry results in a transition of a quasi-Bessel beam into a bow-tie shaped pattern and eventually to a line shaped profile at a larger distance along the optical axis. Furthermore, we analytically estimate and discuss the effects of astigmatism, substrate modes and non-perfect axicons. We find a good agreement between experiment, simulation and analytic considerations. Results include the derivation of a maximal axicon angle related to astigmatism of the illuminating beam, impact of laser diode beam profile imperfections like substrate modes and a longitudinal oscillation of the core intensity and radius caused by a rounded axicon tip.
authors.forename: Angelina
authors.initials: A
authors.lastname: Müller
authors.forename: Matthias C
authors.initials: MC
authors.lastname: Wapler
authors.forename: Ulrich T
authors.initials: UT
authors.lastname: Schwarz
authors.forename: Markus
authors.initials: M
authors.lastname: Reisacher
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Holc
authors.forename: Oliver
authors.initials: O
authors.lastname: Ambacher
authors.forename: Ulrike
authors.initials: U
authors.lastname: Wallrabe