Deterministic rendering of structural color induced by atypical nano-gratings in ultra-precision diamond cutting

[Display omitted] •An innovative diffraction prediction model is firstly proposed and validated to describe the diffractive spectrum of atypical gratings in UPC processes.•The deterministic rendering of structural color is demonstrated by texturing three groups of blazed gratings with controllable topography.•The optimal grating topography design is given for maximizing the region size of color gamut using the novel concept of average saturation.•The sound framework for UPC-induced structural color is established by linking the cutting process parameters to final optical performance. Ultra-precision diamond cutting (UPC) has been recently proposed for fast generation of nano-gratings to render diffractive structural color on various metallic surfaces. However, the complex nanoscale generation mechanism and atypical grating topography provide the significant challenges for deterministic rendering of structural color with standard representations. In this paper, an innovative diffraction prediction model is firstly proposed to describe the diffractive spectrum of atypical gratings under the full considerations of cutting process parameters, double working facets, material optical properties and environmental conditions. The standard CIE 1931 chromaticity diagram for grating-induced structural color is released for color gamut determination and optimization, where the color gamut range is defined by a novel concept of average saturation. The experimental results demonstrate the deterministic generation of three groups of nano-gratings with desired 3D topography, of which the measured angle-dependent diffractive spectrum and rendering color attributes show good agreements with theoretical results. Moreover, the new topography-modulation based strategies for achieving maximal color gamut and manipulating the ternary color attributes are clarified. The outcome of this paper lays the scientific foundations for deterministic rendering and performance enhancement of structural color enabled by UPC processes.