Sol-Gel Replicated Optics Made From Single Point Diamond Turned Masters Exhibit Fractal Surface Roughness

Deterministic optics manufacturing, notably single point diamond turning (SPDT) has matured such that the current generation of machines1 is capable of producing refractive and reflective optics for the visible wavelength region that are quite acceptable for many applications.2 However, spiral tool marks are still produced that result in unwanted diffractive scattering from grating-like features having a spatial frequency determined by the machine feed, tool radius, and other influences such as vibration and material removal effects. Such regular artifacts are the characteristic of deterministic manufacturing methods such as SPDT.