Patent ID: 10139524

Abstract:
A method for designing anti-reflective structure in which plurality of nanostructures formed of projected portions on substrate surface are provided at intervals equal to or less than visible light wavelength, in order to reduce chroma (√(a*2+b*2)) of reflected light with respect to white light to as close to zero as possible, average height of nanostructures from flat portion of substrate surface is 180 nm or greater and 290 nm or less; and filling rate of nanostructures, i.e., ratio of area of bottom surface of nanostructures to area of substrate surface in plan view of anti-reflective structure is defined, in terms of relationship between filling rate and chroma (√(a*2+b*2)) of reflected light from anti-reflective structure with respect to white light, so as to fall within range of ±5% of filling rate at which chroma takes on minimum value.