25 August 2017 Multi-focus beam shaping of high power multimode lasers
Author Affiliations +
Proceedings Volume 10347, Optical Trapping and Optical Micromanipulation XIV; 103470N (2017); doi: 10.1117/12.2273494
Event: SPIE Nanoscience + Engineering, 2017, San Diego, California, United States
Beam shaping of powerful multimode fiber lasers, fiber-coupled solid-state and diode lasers is of great importance for improvements of industrial laser applications. Welding, cladding with millimetre scale working spots benefit from “inverseGauss” intensity profiles; performance of thick metal sheet cutting, deep penetration welding can be enhanced when distributing the laser energy along the optical axis as more efficient usage of laser energy, higher edge quality and reduction of the heat affected zone can be achieved. Building of beam shaping optics for multimode lasers encounters physical limitations due to the low beam spatial coherence of multimode fiber-coupled lasers resulting in big Beam Parameter Products (BPP) or M² values. The laser radiation emerging from a multimode fiber presents a mixture of wavefronts. The fiber end can be considered as a light source which optical properties are intermediate between a Lambertian source and a single mode laser beam. Imaging of the fiber end, using a collimator and a focusing objective, is a robust and widely used beam delivery approach. Beam shaping solutions are suggested in form of optics combining fiber end imaging and geometrical separation of focused spots either perpendicular to or along the optical axis. Thus, energy of high power lasers is distributed among multiple foci. In order to provide reliable operation with multi-kW lasers and avoid damages the optics are designed as refractive elements with smooth optical surfaces. The paper presents descriptions of multi-focus optics as well as examples of intensity profile measurements of beam caustics and application results.
Conference Presentation
© (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Alexander Laskin, Joerg Volpp, Vadim Laskin, Aleksei Ostrun, "Multi-focus beam shaping of high power multimode lasers", Proc. SPIE 10347, Optical Trapping and Optical Micromanipulation XIV, 103470N (25 August 2017); doi: 10.1117/12.2273494; https://doi.org/10.1117/12.2273494


Optics for multimode lasers with elongated depth of field
Proceedings of SPIE (February 22 2017)
Laser remanufacturing technology and its applications
Proceedings of SPIE (January 04 2008)
Latest advances in high power disk lasers
Proceedings of SPIE (February 17 2010)
Economic Justification Of Industrial Laser Applications
Proceedings of SPIE (September 30 1985)
Application of a modern high power laser to heavy section...
Proceedings of SPIE (February 07 2000)

Back to Top