Freeform optical components are gaining popularity with designers due to their ability to improve optical and aerodynamicperformance for many applications. The challenges involved with the manufacturing and metrology of these shapes, whichhave little or no symmetry, has been discussed at previous talks and conferences. This paper will focus on the challengesthat Optimax faced as we scaled up our freeform polishing process from parts with approximately 150 mm diameters, topolishing components with diameters over 600 mm. The large format platform, designed, built, and programmed atOptimax, utilizes a pick-and-place style, 6-axis robotic arm for the polishing motion. In order to scale up the platform fromour existing robotic polishers, a larger robotic arm was used. The associated challenges include: timing considerations forboth the polishing and metrology, obtaining sufficient material removal for reliable measurements, and difficultiesmodelling robot joint positions for collision prevention.These issues have been investigated and mitigated through proprietary techniques and novel solutions, some of which willbe explored in this paper. One such technique currently under development at Optimax is deflectometry; which is a noninterferometricmethod involving fringe reflection and ray tracing to calculate the mid-spatial frequency (MSF) error on apart surface. Deflectometry is able to measure MSF error two orders of magnitude faster than the current method, and hasbeen implemented in-situ, mitigating another challenges involved with larger freeform optics: the logistics of moving themaround a shop floor safely.
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