There are a lot of interesting applications for optical free-form micro-structures. Manufacturing them requires ultra-precision processes that need to be integrated into carefully designed process chains with end-to-end quality control from modeling to post-processing. That is exactly what the European funding project PHABULOµS is working on. Research institutes and specialist SMEs are working together to set up a pilot line with state-of-the art—mainly photonics—manufacturing technology. All European companies can apply to use it in open calls and will receive funding of up to three million euros for pilot applications. In the interview, project coordinator Harry Heinzelmann from the Swiss research and innovation center CSEM in Neuchâtel explains what the pilot line and its use are all about, in which markets free-form micro-optics are unlocking their potential, and why it also always depends on forming networks in projects like PHABULOµS.
Harry Heinzelmann: The aim of our project is to build up competency in Europe to develop and manufacture free-form micro-optics and bring together existing competency in that field in a pilot production line. Companies can use it to implement their project ideas for manufacturing and using free-form micro-optics with our support. Open calls for that will run until the end of 2023. Even those with ideas that are not fully developed are also welcome. We help refine the ideas, provide assistance in submitting the application, and, if the evaluation is positive, small and medium-sized companies will receive grants of up to 90 percent of the project costs, since PHABULOµS receives funding from the EU research framework program Horizon 2020. Alongside leading research institutes like the CSEM in Neuchâtel, the Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP in Dresden, Johanneum Research in Graz, or the Finnish VTT in Espoo, over a dozen companies are also involved. We used the first two years of the project to create the basis for our collaboration, find a common language, compare materials and characterization methods, and demonstrate and optimize the processes in initial pilot applications. We are now offering that competency: Companies receive one-stop support from us in the design and simulation of their free-form micro-optics, and in manufacturing prototypes and later tools for scaling the quantities they can test on our pilot line. The network and our services should remain self-supporting as a one-stop shop after the funding phase and assist companies in developing and integrating free-form micro-optics.
Heinzelmann: The simple answer is—they can be shaped into any form you want. For a long time, the rotating manufacturing process for optics meant having the restriction that they had to be symmetrical. That went as far as micro-optics. New, photonics-based manufacturing approaches such as two-photon absorption, grayscale laser lithography, ultrashort pulse laser ablation, and laser micro-machining in combination with modern digital design and simulation tools offer complete design freedom. They allow whole new optical functionalities to be integrated into components, and highly complex optical imaging to be implemented in a confined space. Consider data glasses for virtual, augmented, or mixed reality (VR-AR-MR), or car headlights, and lighting technology. Since the micro-optics are made of plastic, they are light, and, what’s more, can be manufactured inexpensively, even in large numbers, using established wafer, roll-to-plate or also roll-to-roll processes. That results in major economic potential in a wide variety of markets…
Heinzelmann: More compact, intelligent car headlights that provide optimum illumination of the field of vision without dazzling oncoming traffic. Very light and high-precision VR-AR-MR glasses with displays that optimally present images despite the very short distance from the eye thanks to free-form optics, but also specifically adapted optics for fiber-optic coupling on photonic integrated circuits (PICs) in the field of integrated photonics could become an interesting option. Also involved in PHABULOµs are lighting technology providers that use free-form micro-optics to optimize light scattering for home, office and trade fair lighting for highly uniform illumination, or to implement compact and pleasant interior lighting for buses and trains. Another exciting approach is in the luxury sector, which we implemented as a use case: decorative foils with a highly complex surface profile that create a spectacular shimmer effect in the eye of the beholder. After the prototyping and production of a precise master form, several meters of this foil can be produced per minute using the roll-to-roll process. We can’t wait to see what other application ideas companies approach us with. Wherever optical components are used, our technology could play a role in the future.
Heinzelmann: I’d be glad to. It starts off with the design and simulation of the optical functionalities. Since we also have material providers and process solution manufacturers in the project team, we can also support companies in these fields in an advisory capacity. That also involves taking account of the specific regulatory requirements of the various user markets, such as the fire protection regulations in public transport, or the quality requirements in the automotive sector. Once the choice of material has been made, we get down to the specifics: We look for the right process to manufacture the original free form and the master tool derived from it, which is used to then replicate this form in higher numbers. The scaled procedure—the UV imprint—puts the developed structure into UV-curing polymers. If required, we also support users in the system integration of the free-form micro-optics produced in this way. Because it’s about effectively bringing together existing competency at PHABULOµs, our pilot line is located decentrally at the various institutes. That makes it a virtual line, so to speak, into which the concentrated know-how of the research institutes, and material and process providers flows. Nevertheless, there is one person as a contact for companies, who supports them throughout the entire process. All from one source, so that companies don’t have to search for partners and hidden know-how for this new technology across the whole of Europe.
Heinzelmann: It is indeed the case that mechanical processes such as diamond micro-machining are also used, but the scales with precision in the sub-micrometer range support photo-lithographic and laser-based processes. The same goes for quality control within and outside the line using different spectrometric, hyperspectral, interferometric, microscopic or X-ray fluorescence processes. However, the later process stages, such as the UV imprint, injection molding, roll-to-roll imprinting, or also the various thin-film processes for functional coating of the optics have a high mechanical content. It’s about having an effective mix. The rule of thumb is that we use photonics where maximum precision is required in prototyping, and mechanics for high volume production with maximum throughput. We experimented a lot in the first two years to develop the optimum process chains for different use cases.
Heinzelmann: It already starts with the design, which must take account of the later scalability and keep an eye on the costs. And it’s important to closely accompany the process in measurement terms in order to ensure the necessary precision in the prototyping, tool construction and later for high quantities. However, users are mostly very quality-conscious and have their own Six Sigma requirements with corresponding measurement equipment. We don’t need to reinvent that.
Heinzelmann: Right now, the open calls have top priority, of course. Funding is available until the end of 2023 to support companies in developing pilot applications. Ideas and applications are welcome! We are building up the marketplace, in which, by the way, many companies from the LASER community are represented, in parallel. Providers of manufacturing processes, materials or also measurement technology are likewise welcome here, as are specialists for design and simulation, and, of course, interested users from a wide range of industries. We want to use the marketplace to consolidate the structures and networks created during the funding phase. After all, the pilot line should also remain as a one-stop shop in the future and pool know-how. It would be conceivable to create a specific job exchange or offer training courses in the marketplace. We invite anyone who is interested to visit our stand at LASER World of PHOTONICS from June 27 to 30—but I advise you to discuss your ideas and applications with us beforehand.
Heinzelmann: By pooling existing competency, we allow a new technology field to be opened up quicker and more easily. The know-how needed to establish a market for free-form micro-optics is already there in Europe. We bring it together along the virtual pilot line and can use our network to provide interested users with both theoretical and practical answers to all questions relating to the development and integration of free-form micro-optics. I think that’s the most effective way to develop this exciting technology and harness its innovative potential across the board.
More information about the project and the open calls can be found at https://phabulous.eu/