Title advances in optical fabrication for astronomy

Freeform geometrical optics II: from parametric representation to CAD/CAM

“…This kind of machines succeed easily as the surfaces have a revolution symmetry. On the other hand, a true freeform optics defined as "having no axis of symmetry on or off the part" [7] is not described by a single equation. In fact, as it has been shown in [12], a simple equation is used to calculate any surface that is solution to any lens design but its result can be extended to several terms.…”

“…Imaging optics is a second optical design interesting domain for freeform optics. Non-symmetrically rotational surfaces of head-up displays [5] and line-scan cameras [6] designs have experienced improvements in image quality and astronomic instruments have been studied or manufactured with a freeform approach [7]. Indeed, this new way of designing optics offers several advantages as the number of surfaces in a complex optical system reduces.…”

“…A freeform surface mathematical representation has also been recently proposed [8]. Nevertheless, manufacture methods and processes evolve to obtain symmetrical and asymmetrical freeform surfaces [7,9,10]. On the other hand, freeform design methods for imaging optics have been studied and assessed a few years ago [11].…”

“…The authors of this paper have recently released a new principle for freeform design [12]. Advances in freeform manufacturing has also been reported [7]. In this paper, the authors focus on the step that permits the designed optical element to be readable by a Computer Numerical Control (CNC) machine or in additive optics [13,14] manufacturing.…”