Apparatus and method for laser treatment of a biological material

US8083731B2 · kind B2 · utility

Assignees

• WaveLight GmbH · DE
• Fraunhofer-Gesellschaft zur förderung der angewandten Forschung e.V. · DE

Inventors

• Andreas Tunnermann · Weimar, DE
• Klaus Vogler · Eckental, DE

Key dates

• Filing date: Mar 2, 2007
• Grant date: Dec 27, 2011
• Expiry date: Aug 26, 2030

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61F2009/00872
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

An apparatus for laser processing of a material, in particular the eye cornea, emits on to the material a train (18′) of laser radiation pulses having a pulse duration in the femtosecond range. The pulse train comprises a multiplicity of successive pulse groups, each pulse group comprising at least two laser radiation pulses (20′, 22′). The pulses of a pulse group are directed at substantially the same processing site of the material, but the pulses of successive groups are directed at substantially different processing sites of the material. According to the invention the time interval between successive laser radiation pulses of a pulse group is in the nanosecond range. In particular, the intensity or energy of the pulses within a pulse group is graduated, in such a way that a preceding prepulse (20′) has substantially lower intensity or energy than a following main pulse (22′).