Freeform optical zoom systems to enhance laser materials processing applications

Lasers have become indispensable for many industrial materials processing applications. Some applications might not only favor a specific beam irradiance distribution but can benefit additionally from time-varying distributions. For example, a dynamic beam shaping system based on scanning mirror optics can be used for laser beam hardening, proving a variable scan width to adapt the energy spread to different local heat flow conditions. The use of deformable mirrors and spatial light modulators have been also proposed to achieve similar adaptive laser beam irradiance control. Even though adaptive optics concepts are very versatile, they add complexity, their optical efficiency might be significantly reduced and they might tolerate only limited energy densities.

Solution: freeform optical zoom systems based on moveable lenses

The Brussels Photonics Team B-PHOT of the VUB has developed a class of freeform optical zoom systems based on moveable lenses that allows to change the size and shape of the initial laser beam in a very flexible manner. So far, such enhanced dynamic functionalities have never been demonstrated for likewise simpler lens-based zoom systems. The here shown example is a dynamic beam delivery system that can be used for laser beam hardening, where the freeform optical system is capable of homogenously illuminating a rectangular target region with variable size and aspect ratio. Similar arguments also apply for laser additive and subtractive manufacturing processes, welding and cutting, laser beam writing of channels or waveguides or related applications, where the flexibility we provide with our solutions can help to improve both the speed and the quality of the processed items.

Competitive advantages

  • simpler structure compared to adaptive optics solutions
  • very high optical efficiency and applicable to high laser powers
  • compact solutions, yet achieving excellent overall optical performance
  • offering solutions for a wide range of applications

Interested parties can contact

VUB TechTransfer
Hugo Loosvelt
[T]: +32 (0)2 629 38 65 or 22 07
Brussels Photonics Team - B-PHOT
Fabian Duerr

Patent details

European patent application filed on 24 September, 2015, EP15186595.3

Download a printable pdf here.