Backlight and display system using same

US8469575B2 · kind B2 · utility

Assignee

• 3M INNOVATIVE PROPERTIES COMPANY · US

Inventors

• Michael F. Weber · Shoreview, US
• Timothy J. Hebrink · Scandia, US
• Timothy J. Nevitt · Red Wing, US
• John A. Wheatley · Stillwater, US
• Craig R. Schardt · Saint Paul, US
• Rolf W. Biernath · Wyoming, US
• William J. Bryan · Granby, US
• Andrew J. Ouderkirk · Windom, US
• David G. Freier · Windom, US
• Myron K. Jordan · Apple Valley, US
• Kristopher J. Derks · Woodbury, US
• Zhaohui Yang · Beijing, CN
• Edward J. Kivel · Stillwater, US

Key dates

• Filing date: May 19, 2008
• Grant date: Jun 25, 2013
• Expiry date: Mar 14, 2030

Classification

• Technology area (CPC G): Physics
• CPC primary: G02F1/13362
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A backlight that includes a front reflector and a back reflector that form a hollow light recycling cavity including an output surface is disclosed. The backlight further includes one or more light sources disposed to emit light into the light recycling cavity. The front reflector includes an on-axis average reflectivity of at least 90% for visible light polarized in a first plane, and an on-axis average reflectivity of at least 25% but less than 90% for visible light polarized in a second plane perpendicular to the first plane.