Light directing film and method for making the same

US9810817B2 · kind B2 · utility

Assignee

• 3M INNOVATIVE PROPERTIES COMPANY · US

Inventors

• Alan B. Campbell · Santa Rosa, US
• Dale L. Ehnes · Cotati, US
• John F. Van Derlofske, III · Minneapolis, US
• Mark R. Dupre · Oakdale, US
• Stephen J. Dreyer · North St. Paul, US
• Patrick H. Marushin · Windom, US
• Todd M. Johnson · Moorpark, US
• Bryan V. Hunt · Anoka, US

Key dates

• Filing date: Apr 1, 2009
• Grant date: Nov 7, 2017
• Expiry date: May 7, 2031

Classification

• Technology area (CPC G): Physics
• CPC primary: G02F1/133615
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A light directing film includes a structured major surface with a plurality of microstructures extending along a first direction. Each microstructure has a first region and a second region different from the first region, a substantially constant height in the first region and a non-constant maximum height in the second region greater than the substantially constant height in the first region, and a same lateral cross sectional shape in the first region and the second region.