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The conventional state-of-the-art manufacturing processes of aspheric reflective optics normally consists of the following steps: • Production of the glass blank; • Machining and grinding of the blank to approximate shape, inclusive of backside lightening; • Deterministic figuring and polishing. Deterministic figuring and polishing are iterative processes performed by IRP (Intelligent Robot Polishing) or MRF (Magneto-Rheological Figuring) or IBF (Ion-Beam Figuring), which iteratively converge to the targeted performance with guidance from accurate metrology information. The process capability of these one-off methods is well established, but hardly cost-effective for any small/large series production because of the need to repeat the entire process for each product unit. Differently from the conventional methods, the Cold Shaping Optics manufacturing technology consists of precisely shaping an inexpensive thin glass sheet (⪆ 1 mm) over a high precision mandrel and freezing its shape over a low-cost substrate by means of an epoxy adhesive layer. The mandrel must have the same surface shape accuracy specified for the desired optics. However, in a mini production series, the Cold Shaping Optics technique can reduce the recurrent production costs by amortizing the cost of the re-usable shaping mandrel over multiple product units allowing the manufacture of high-performance reflective optics at a fraction of the cost of traditional grinding and polishing methods. In addition to that, the possibility of actively changing the shape of the mandrel allows the series production of optics with different shapes from the same mandrel, hence further reducing the cost paradigm. In this paper we report the results obtained during the development of first prototype mirrors of 380 mm diameter.
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