Freeform surfaces on optical components have become an important design tool for optical designers. Non-rotationally symmetric optical surfaces have made solving complex optical problems easier. The manufacturing and testing of these surfaces has been the technical hurdle in freeform optic’s wide-spread use. Computer Numerically Controlled (CNC) optics manufacturing technology has made the fabrication of optical components more deterministic and streamlined for traditional optics and aspheres. Optimax has developed a robust freeform optical fabrication CNC process that includes generation, high speed VIBE polishing, sub-aperture figure correction, surface smoothing and testing of freeform surfaces. Metrology of freeform surface is currently achieved with coordinate measurement machines (CMM) for lower resolution and interferometry with computer generated holograms (CGH) for high resolution irregularity measurements. Keywords: Freeform, optics, manufacturing, VIBE, metrology.

1. INTRODUCTION

Freeform optics have become a popular tool with optical engineers and integrators for imaging and illumination applications.^1-4 These optical surfaces lack radial symmetry and may have complex shapes that solve a variety of optical design problems. However, the availability of freeform optics has been limited by the manufacturing and testing of these unique optics.

In traditional optics manufacturing, the optic is created by lapping the correct radius using dedicated tooling, followed by pitch polishing in a slow iterative process. The introduction of CNC optics manufacturing replaced the need for...