29 August 2016 Enhanced performance of refractive laser beam shapers through additional phase control at focus
Author Affiliations +
Abstract
Laser beam shaping at focus or focal beam shaping is essential for many applications. The most common approach makes use of the Fourier transforming properties of lenses to generate at their focal planes the desired irradiance patterns, e.g., the flattop. There are two inherent limitations for this approach. First, the shaping quality depends strongly on the dimensionless parameter β. In the case of a long focal length or small beam sizes giving a small β value, additional beam expanders are needed to achieve a satisfying irradiance pattern at the focus. Second, without considering the phase, the irradiance patterns beyond the focal plane are not controlled. We propose a different approach with two plano-aspheric lenses that allow control of both irradiance and phase at focus. The design method comprises an extended ray mapping procedure combined with backward wave propagation from focus. With this design approach, the shaping quality is guaranteed without the possible need for extra beam expanders, offering the potential for a more compact system with fewer elements. Through the additional phase control, the depth of focus is enlarged to a large extent and the designed system becomes more tolerant.
© 2016 Society of Photo-Optical Instrumentation Engineers (SPIE)
Meijie Li, Meijie Li, Youri Meuret, Youri Meuret, Michael Vervaeke, Michael Vervaeke, Hugo Thienpont, Hugo Thienpont, Fabian Duerr, Fabian Duerr, } "Enhanced performance of refractive laser beam shapers through additional phase control at focus," Optical Engineering 55(8), 085106 (29 August 2016). https://doi.org/10.1117/1.OE.55.8.085106 . Submission:
JOURNAL ARTICLE
9 PAGES


SHARE
RELATED CONTENT

Freeform optical design of an XY-zoom beam expander
Proceedings of SPIE (April 26 2016)
An optical system design that converts a Gaussian to a...
Proceedings of SPIE (October 14 2015)
Laser beam shaping via conventional design software
Proceedings of SPIE (October 29 2001)
Characteristics of ZnSe aspheric beam shaper for CO2 laser
Proceedings of SPIE (October 29 2001)
The power of negative thinking
Proceedings of SPIE (September 01 2010)

Back to Top