title: [Principle and mechanism of action of an ArF excimer laser system with a scanning and rotating slit aperture].
abstract: This study was designed to investigate the quality of a scanning and rotating slit delivery system of an ArF-Excimer laser (Nidek EC 5000). The ablation patterns on PMMA samples were examined by REM. The influence of inhomogeneities in the beam profile was simulated on a computer and compared with a conventional large-area ablation system. The impairment of the ablation rate by radiation absorption of the ablation plume was measured as a function of the repetition rate and the application of a fixation ring. The scanning and rotating slit delivery system creates extremely smooth ablation patterns. The delivery system is very tolerant of small-beam inhomogeneities. The ablation rate is very sensitive to the dynamics of the ablation plume. Although the operating procedure takes less time with a large-area ablation system, a scanning and rotating delivery system has the advantage of reliable and homogeneous removal of corneal tissue.
authors.affiliation: Laser Zentrum Hannover.
authors.forename: H
authors.initials: H
authors.lastname: Lubatschowski
authors.forename: O
authors.initials: O
authors.lastname: Kermani
authors.forename: H
authors.initials: H
authors.lastname: Welling
mesh_terms: D003198:Computer Simulation; D004867:Equipment Design; D006801:Humans; D054018:Lasers, Excimer; D008768:Methylmethacrylates; D008953:Models, Anatomic; D018903:Photorefractive Keratectomy / Q000295:instrumentation*
chemical_list: D008768:Methylmethacrylates
vernacular_title: Prinzip und Wirkungsweise eines ArF-Excimerlasersystems mit scannender und rotierender Schlitzblende.