Microtextured antireflective surfaces with reduced diffraction intensity

• US 20050094277A1
• Filed: 11/01/2004
• Published: 05/05/2005
• Est. Priority Date: 10/30/2003
• Status: Active Grant

• Current Assignee: Niyaz Khusnatdinov, Tanwin Chang
• Original Assignee: Niyaz Khusnatdinov, Tanwin Chang
• Inventors: Khusnatdinov, Niyaz, Chang, Tanwin
• Granted Patent: US 7,252,869 B2
• Time in Patent Office: Days
• US Class Current: 359/601
• CPC Class Codes: F41H 3/00 Camouflage, i.e. means or methods for concealment or disguise for vessels B63G8/34, B63G13/02 ; sound camouflage, i.e. simulating gun fire noise, F41A33/04; dummy or decoy targets F41J; chaff per se F41J2/00; ammunition for dispensing chaff F42B5/15, F42B12/70; radar absorbing fabrics H01Q17/005
• CPC Class Codes: G02B 1/11 Anti-reflection coatings
• CPC Class Codes: G02B 1/118 having sub-optical wavelength surface structures designed to provide an enhanced transmittance, e.g. moth-eye structures
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10T 428/24355 Continuous and nonuniform or irregular surface on layer or component [e.g., roofing, etc.]
• CPC Class Codes: Y10T 428/261 In terms of molecular thickness or light wave length

Abstract

A microstructured antireflective texture is disclosed comprised of an engineered array of protuberances arranged on a non-periodic lattice. The average distance between said protuberances is in the subwavelength regime of the waveband for which the antireflective effect is desired. The non-periodic arrangement of protuberances acts to suppress blue-green backscattered light that is commonly seen diffracting from antireflective textures that use strictly periodic lattice arrangements. Embodiments of the invention include the randomized square pattern, and the quasicrystal pattern.

Claims

1. An article that is a surface with antireflective properties wherein said antireflective properties are achieved by alteration of surface topology.

2. An article of claim 1 wherein said surface topology is comprised of an engineered array of protuberances wherein the average distance between neighboring protuberances is smaller then the optical wavelength of incident light, and said protuberances are arranged on a non-periodic lattice.

3. An article of claim 2 wherein said engineered array of protuberances is arranged in a randomized pattern where the randomization process involves adding a random limited displacement to the positions of a prototype periodic lattice pattern.

4. An article of claim 2 wherein said engineered array of protuberances is arranged in a quasiperiodic pattern.

5. An article of claim 2 wherein said engineered array of protuberances is arranged in a randomized pattern where the randomization process involves adding a random limited displacement to the positions of a prototype quasiperiodic lattice pattern.