Optical stack and optical system

US10670867B2 · kind B2 · utility

Assignee

• 3M INNOVATIVE PROPERTIES COMPANY · US

Inventors

• Zhisheng Yun · Woodbury, US
• Andrew John Ouderkirk · Kirkland, US
• Timothy L. Wong · Windom, US
• Erin A. McDowell · Afton, US
• Gregg A. Ambur · River Falls, US

Key dates

• Filing date: May 13, 2019
• Grant date: Jun 2, 2020
• Expiry date: May 13, 2039

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B2027/0138
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An optical stack includes first and second lenses, a partial reflector, a reflective polarizer, and a retarder. The reflective polarizer is curved about two orthogonal axes and includes at least one layer that is substantially optically uniaxial at at least one location. An optical system includes the optical stack disposed between an image surface and an exit surface. The optical system is configured such that substantially any chief ray transmitted from the image surface to the exit surface is first incident on the reflective polarizer at an angle of incidence less than 30 degrees.