Serial precision is all about the right design. 17. February 2022 The close interplay between optics design and manufacturing offers planning and cost certainty to WILD‘s customers and guarantees that design focuses on manufacturing from the outset. On the product side, there are ever more complex geometrical shapes, advancing miniaturisation and higher requirements for precision, quality and cleanliness. On the manufacturing side, new materials and innovative process and measurement techniques: to survive the competition in high-performance optics, the entire workflow from optics design to precise manufacturing and quality control must be perfectly choreographed. At the same time, it is essential to keep a watchful eye on the economic factors. When development and production go along different paths, designers will often succumb to the temptation to over-optimise, pushing subsequent manufacturing to its very limits. The WILD Group follows a different philosophy. “We know how essential the interplay between design and manufacturing is when it comes to ensuring a time-efficient and cost-efficient production of high-quality optics, both in small and large numbers. Our in-house production and the inherent understanding of manufacturing tolerances and potential cost drivers offer a series of advantages. The same applies to the Group‘s combination of diverse skills – from feasibility studies to modern simulation methods and prototyping to serial production“, says Photonic Site Manager Stefan Zotter. LOOK BEYOND THE PROBLEM AT HAND In essence, the task of optics design is to efficiently implement application-specific imaging quality and light distribution. Therefore, it is not limited to the design of optics, but also involves detailed sensitivity and tolerance analyses. “We examine all potential manufacturing tolerances such as, for instance, production-related deviations from the nominal radius of the lens, refractive index fluctuations of the glass or the fit clearance between the lens and the lens mount. All of these factors can have an impact on the performance parameters of the optical system. Only if you analyse all undesirable influences and eliminate them already in the design phase will you ultimately create a system that delivers the required optical performance – from the very first prototype“, explains Gerold Aschinger, Head of Development at Photonic. For this reason, the developers at WILD and Photonic critically scrutinise the general setting and discuss it with the customer before they begin with the actual design. “This has often allowed us to find and implement more affordable and more suitable solutions.“ FLEXIBILITY IS THE KEY TO TOP DESIGN This open-minded approach can in part be attributed to the breadth of manufacturing capabilities available within the WILD Group. Developers can be quite flexible in the interpretation of their design. “A system is not geared towards a specific and perhaps inefficient manufacturing process. Instead, we optimise the system for the manufacturing method that is best suited to solving the problem at hand and that generates the highest possible value for the customer“, explains Stefan Werkl, Head of the Business Unit Optical Technologies at WILD GmbH. SHORTER TIME TO MARKET Another advantage of this manufacturing-focused design is that “the close interplay between optics and mechanics design significantly reduces the time to market“, as Optics Designer Rembert Fertner points out. Since the simulation already takes the system‘s later feasibility into account, the number of correction loops on the prototypes decreases significantly. “The optics designers at WILD and Photonic use the Zemax© OpticStudio simulation software for imaging optics and LightTools for lighting optics. When the standard functions of these tools no longer suffice, our developers expand them by writing scripts, some of them in Python“, Stefan Zotter explains. Yet their field of activity is not limited to simulation: The results are regularly verified in experiments on an optical table or in prototyping and the measurement results from production are used to update the tolerance models in the designs. Zotter is convinced that “these valuable feedback loops between manufacturing and optics design are what sets the WILD Group apart from conventional optics design studios and optics manufacturers“. EXPERIENCE FROM DIFFERENT FIELDS WILD Group customers also benefit from the technology partner‘s long-standing experience in various fields. The experts in Völkermarkt mainly focus on imaging optics systems and free form optics. Photonic can resort to a wealth of know-how in lighting optics, which is required in almost all optical applications. Photonic Business Developer Joachim Enengl cites fluorescence-assisted tumour resection as an example: “This clearly demonstrates that, in addition to modern display and camera technology, lighting plays a decisive role in implementing augmented reality solutions in medical technology. You can only develop a device that offers added value to the user in the operating theatre if you possess the necessary knowledge of surgery procedures and the underlying physiological principles, and the technical expertise“, insists Joachim Enengl. The same is also true for in-vitro diagnostics, where the corresponding light technology is a major requirement for the multispectral evaluation of molecular biologic samples. HIGH-END EQUIPMENT The WILD Group has a whole array of high-end optical measurement equipment at its disposal. Photonic, for instance, recently made considerable investments in its optics and electronics laboratory, installing new assembly sites for prototypes and demonstrators. These are equipped with cameras and the necessary IT, so that the assembly sites can be used both for serial production on site and for virtual training. The technical highlights of the new class 4 laser optics laboratory include a CAS 140D spectrometer by Instruments Systems with integrating sphere for high-precision spectral light measurement. “The new spectrometer offers greater sensitivity and performance, which boosts our ability to measure fluorescence signals. Its integrated light-field camera allows for significantly quicker measurements of the light distribution of flood lamps“, explains Stefan Preißer of Photonic Business Development. This has increased the volume of findings obtained from functional samples, leading to even greater efficiency in development. The new equipment also includes an LMK camera for luminance and colour measurement and a camera system used to characterise the VIS and NIR content in the energy distribution of illumination fields. Moreover, a power meter for the measurement of lasers in the NIR range and faster photodiodes for measuring fluctuations in lasers were added to WILD‘s arsenal. Furthermore, Photonic has created a database of light bulbs which was linked to software for spectral combination. Such knowledge at the push of a button can shorten the concept phase, since the search for light sources can be done much quicker. All in all, the quality of the equipment currently available within the WILD Group is similar to that of test laboratories. As a result, optics designers can directly compare their measurement results to those of the certification authority, thus minimising waiting time, accelerating development and reducing lead time to production.