Optical element with a porous low refractive index layer having a protection layer

US10502869B2 · kind B2 · utility

Assignee

• 3M INNOVATIVE PROPERTIES COMPANY · US

Inventors

• William D. Coggio · Hudson, US
• Ramesh C. Kumar · Maplewood, US
• John A. Wheatley · Stillwater, US
• Michael L. Steiner · New Richmond, US
• William F. Edmonds · Minneapolis, US
• Lan H. Liu · Windom, US
• Encai Hao · Woodbury, US
• Robert F. Kamrath · Mahtomedi, US
• John J. Stradinger · Roseville, US

Key dates

• Filing date: Oct 20, 2011
• Grant date: Dec 10, 2019
• Expiry date: Oct 20, 2031

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/24997
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An optical article includes an optical element, a low refractive index layer disposed on the optical element having an effective refractive index of 1.3 or less and a polymeric protective layer disposed on the low refractive index layer. The low refractive index layer includes a binder, a plurality of metal oxide particles dispersed in the binder, and a plurality of interconnected voids. The polymeric protective layer does not increase an effective refractive index of the optical article by greater than 10%.