 The 21st century is the century of the photon and one major topic within is the laser. Lasers are becoming more and more powerful tools in everyday application because it's very flexible to use light and shape it and choose specific parameters for your application. We are looking into material processing, trying to cut steel or glass and also work on surface functionalization. Therefore we have to change the beam profile that is coming out of the laser into a more suitable way. Usually when you have a laser there comes a Gaussian beam which means this very bright intensity in the center and the intensity drops down to the edges. What we are interested in is changing those focal intensity distributions to more suitable patterns like a top hat or a donut profile to make it even more suitable for the application, make the application faster or even open up the possibility for new applications that can't be done in another way. We tried an approach where we thought of light in a different way, not only as an intensity distribution but as an electromagnetic wave. The idea we were implementing is originally coming from phase shifting microscopy. What we wanted to do is change the phase distribution of the incoming Gaussian beam before it's focused on the material. So what we did is we created a phase plate that is basically a planoparallel plate with a small step with a cylindrical symmetry and a certain width. In our experiments we used 10 millimeters because it's just a good beam diameter. The width of the incoming beam is chosen in a way that one over e-square diameter of the Gaussian beam matches exactly the diameter of the step on the phase plate. With that we create a phase shift of the central part compared to the outer part of pi. With that phase change we introduce a shift in the intensity distribution and after focusing that newly created intensity distribution we have a top hat distribution in the focus. What's even better, we're not only having one top hat distribution but we are actually creating three top hat distributions in the focal region which are all slightly different in their width and height. Additionally we get the feature that in between we have a donut shaped distribution with a varying depth so you can actually tune the profile you want to use by changing the distance of your material to the lens that you employ for focusing. Well you remember that our original question was how to change that Gaussian distribution into something more suitable for material interaction. What we did is we insert our phase plate into a commercial setup with a femtosecond laser and insert also a beam expander to adapt the beam size to match the beam shaping condition and then we did single spot experiments on stainless steel to see if the calculated beam profiles in the focal region actually showed up that we could see different profiles on the stainless steel created with that new approach. And we succeeded there and we're very happy about it and then of course ask ourselves what applications can we go for where we can improve the results with that newly approach by implementing that phase plate. We looked at two different things. The first thing was nanostructuring. We generated so-called LIPS, meaning laser-intuced periodic surface structures. They have this nice feature that according to the polarization of the laser beam they are lining up on the surface. Using that top head distribution compared to the Gaussian distribution we were able to significantly improve the homogeneity of that surface profile and even speed up the process by a factor of two. We were able to structure an area with 10 by 10 millimeters within 30 seconds. The second application we worked on is microstructuring. We were able to show that if you use a donor distribution or a top head distribution that you get very neat lines with very steep edge profiles and you don't have that well-known collapsing of your line, of your micro channel because when you use a Gaussian distribution there's too much energy in the center and this was completely solved by using the two different profiles. You get much better contrast for example if you use that for micro-engraving or marking or something like that. Why is it relevant to be able to structure surfaces like that with different beam profiles? Well, for the first thing the obvious thing always is saving energy, being faster, being more precise on processes that are already known. But what is also very important is to be able to create new processes, to step forward and to have applications that are coming out of the lab that open up new possibilities creating things we haven't seen before. And I would like to give you one example of that. When you look at the nanostructuring, the creation of that periodic surface structure, there you have the chance to structure the surface in a way that it's for example self-cleaning like from nature, from the lotus effect. And you can do that without using any chemistry or any additional process just by using the laser light in a certain distribution and in a certain setup so you can even scale those processes to square meters which opens up fully new possibilities on using such surfaces and maybe even creating new applications we can't think of today. There are mainly two topics. The first one is there still work in the research part left. As you probably noticed, we're still talking about rotational symmetric profiles and for the scanning that goes in an x and y direction a square or rectangular distribution would be even more efficient to speed up the process. So we're working on ways to implement the method we just described to create square or rectangular distributions. The second part is taking it really out of the lab go to different industrial applications where you can actually use much more powerful lasers to really do that upscaling on the square meter region.