Light extraction films for increasing pixelated OLED output with reduced blur

US8469551B2 · kind B2 · utility

Assignee

• 3M INNOVATIVE PROPERTIES COMPANY · US

Inventors

• Martin B. Wolk · Woodbury, US
• Sergey Lamansky · Redmond, US
• David Scott Thompson · Lake Elmo, US
• Zhaohui Yang · Beijing, CN
• Jun-Ying Zhang · Perrysburg, US
• Encai Hao · Woodbury, US
• William Blake Kolb · Windom, US
• Audrey A. Sherman · Windom, US
• Kevin R. Schaffer · Woodbury, US

Key dates

• Filing date: Oct 20, 2010
• Grant date: Jun 25, 2013
• Expiry date: Jan 3, 2031

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B29C2035/0877
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

Optical films for enhancing light extraction from self-emissive pixelated OLEDs, without introducing significant pixel blur, are disclosed. The extraction films include a flexible carrier film, and a first and second layer carried by the carrier film. The first layer has a nanovoided morphology, includes a polymer binder, and may have a refractive index less than 1.35 or 1.3. An embedded structured surface of light extraction elements is formed between the first and second layers. The extraction film includes a major coupling surface for attachment to an outer surface of the light source. The film is configured such that a land portion between the structured surface and the major coupling surface is thinner than a specified amount, e.g., less than 50, 25, or 10 microns, or less than a thickness of the carrier film.