REFLECTIVE POLARIZER AND DISPLAY DEVICE HAVING THE SAME

• US 20090262422A1
• Filed: 07/01/2009
• Published: 10/22/2009
• Est. Priority Date: 06/03/2005
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Nelson, Eric W., Cross, Elisa M., Invie, Judith M., Zhang, Wei Feng
• Granted Patent: US 7,724,434 B2
• Time in Patent Office: Days
• US Class Current: 359/488
• CPC Class Codes: G02B 5/305 including organic materials, e.g. polymeric layers
• CPC Class Codes: G02F 1/133536 Reflective polarizers G02F1/13362 takes precedence
• CPC Class Codes: G02F 1/133545 Dielectric stack polarisers

Abstract

A reflective polarizer suitable for use in a display device is disclosed herein. The reflective polarizer comprises: a multilayer optical film comprising alternating layers of first and second polymeric layers that reflects light of a first polarization state and transmits light of a second polarization state, wherein for normally incident light of the second polarization state, the reflective polarizer has an internal percent transmission of at least 95% at 410 nm, and at most 25% at 380 nm. Also disclosed herein is a display device comprising the reflector polarizer.

Claims

1. A reflective polarizer suitable for use in a display device, the reflective polarizer comprising:

a multilayer optical film comprising alternating layers of first and second polymeric layers, the first and second polymeric layers having refractive indices along an in-plane x-axis that differ sufficiently to substantially reflect light of a first polarization state, the first and second polymeric layers having refractive indices along an in-plane y-axis that are matched sufficiently to substantially transmit light of a second polarization state, wherein the x- and y-axes are orthogonal, wherein at least one of the first and second polymeric layers comprises naphthalate functionality; and

first and second skin layers disposed on opposite sides of the multilayer optical film;

wherein at least one of the first and second polymeric layers and the first and second skin layers comprises an ultraviolet (UV) absorber that absorbs UV light and transmits visible light, such that for normally incident light of the second polarization state, the reflective polarizer has an internal percent transmission of at least 95% at 410 nm, and at most 25% at 380 nm.

2. The reflective polarizer of claim 1, wherein at least one of the first and second skin layers comprises the UV absorber.