3D Laser Beam Shaping: The True Potential of Laser Based Manufacturing

Manufacturing with lasers has advanced from the purely science fiction ideas of the 1950's and 60's to be a real world, critical step, in the manufacture of an enormous range of products. Over the years a range of new techniques and processes have been developed in research labs and companies across the world. One of the more important of these has been the development of beam-shaping technology.
Laser processing of material is driven by transfer of energy from the laser beam into the material, and can be a mixture of thermal, photo-chemical and optical non-linear effects. By changing the shape of a laser beam where it impacts a material it is possible to mould how and where energy is transferred. This then allows for more precise control of the laser-material interaction and hence of the manufacturing process itself.
This has led to improvements in the way cutting, welding and similar processes work with improvements in quality and efficiency. However these beam-shaping technologies are limited. They only shape in two dimensions, i.e. in a single focal plane. This is not a big problem for "surface processes" as the plane at which the laser beam is formed into the right shape can be made, with some care in focussing the beam, to be the surface of the material. However for materials with an irregular shape, imprecise thicknesses, or that are at least partially transparent to the laser, this is a challenge. It is also a challenge when trying to take advantage of the range of exciting new technologies based on non-linear phenomena.
Non-linear laser processes typically limit the laser material interaction to only those regions of the laser beam where there is an extremely high intensity i.e. at the focus. By moving the focus inside the material it then possible to manufacture from the inside out. However, because the light interacts with the material not just on the surface but throughout the focal volume two dimensional beam shaping is insufficient; full 3D control is instead required.
Within this research project we will take advantage of the wave-nature of light. Through careful shaping of a glass optic it is possible to bend different parts of a laser beam to overlap in a controlled manner. As the beams overlap they will interfere creating regions of high and low energy. Though careful calculation it is possible to manipulate this with each optic designed to give a precise interference pattern which results in a specific energy distribution; to shape the beam in three dimensions.
By shaping the laser beam throughout the focal region it will be possible to open entirely new methods of manufacture from more effective means to cut toughened glass (like mobile phones or iPads), dice and drill semiconductors (for computer chips), make precision medical devices, and create new and much more effective surgical procedures. The potential applications are truly enormous, transformative and will change how and what we can manufacture.

UK manufacturing is a priority area for the current government. As high-tech processes become better understood the number of companies able to deliver them increases; the UK must stay at the cutting edge. Laser based production processes offer many such opportunities.
This project will deliver an entire new capability to laser based production processes. The ability to simply and cheaply shape laser beams in 3D. Delivering a blueprint for developing or substantially improving processes for a huge array of applications.

Economic and Commercial
In the short term, PowerPhotonic (Dalgety Bay, UK), specialising in the manufacture of precision 3D free-form optics (essentially the only company to offer this), will gain the most valuable immediate benefit. Their business is to provide a range of optical elements designed to meet customer requirements across the full spectrum of optical applications. There is considerable interest in the laser-based manufacturing community at present in the possibilities for Bessel beams and 3D beam shaping in general but, at present, little understanding of exactly what the capabilities are and exactly what 3D optic designs are required. A simple set of analytical equations to design 3D beam shaping optics and tests on their effect on specific applications combined with PowerPhotonic's unique manufacturing capabilities will create an entirely new market which they will be ideally positioned to service. Gooch & Housego (Illminster, UK) will similarly gain new markets, either through producing faceted optics or as a supplier of pre-forms to PowerPhotonic.
The first customer for this new process capability will be Oxford Lasers (Didcot, UK), a laser systems integrator who also provides job-shop capabilities to industry. While there is a specific application to be addressed in the form of drilling non-circular holes in semi-conductors there are a wide range of other manufacturing processes where benefit can be found by moving away from Gaussian beam shapes - the potential impact to UK manufacturing in gaining an advantage in this area is enormous.
The resulting economic impact is potentially huge, not just for the project partners but across UK manufacturing as these new processes disruptively act in existing, and enable entirely new, markets. To maximise this we will ensure that knowledge is transferred to the wider engineering and laser industry sectors through the strategies outlined in "Pathways to Impact".

Societal
The full impact of 3D beam shaping will extend far beyond the manufacturing sector with the associated economic and social benefits that a strong, high tech, industry sector will bring. One example is expected to be in the area of medical device fabrication and in surgical laser processes. Restrictions on size and materials (due to bio-compatibility) mean that there is constant demand for new capabilities when designing and manufacturing medical devices. 3D beam shaping will open many new capabilities for the manufacturing of new life saving processes. Finally students and post-docs, together with staff at the project partners working on the project, will acquire wide-ranging skills including in laser physics, optics, engineering, process and experimental design, programming and data analysis, which can be employed in academia and high-tech industries.

The public and policy-makers
Activities outlined in "Pathways to Impact" will raise public awareness of the importance of manufacturing, laser based manufacturing, and ultimately of the new capability developed within this project. A well informed pubic will then be able to make informed decisions on the importance of research, as well as the wider industry when considering what is deserving of taxpayer support