Hybrid polarizer

Abstract

A hybrid polarizer includes an absorbing element having a first major surface and a second major surface. The hybrid polarizer also includes a first birefringent reflective polarizer disposed on the first major surface of the absorbing element, the first birefringent reflective polarizer having a first pass axis and a first block axis. The hybrid polarizer further includes a second birefringent reflective polarizer disposed on the second major surface of the absorbing element, the second reflective polarizer having a second pass axis and a second block axis.

What is claimed is: 
     
         1 . A hybrid polarizer, comprising:
 an absorbing element having a first major surface and a second major surface;   a first birefringent reflective polarizer disposed on the first major surface of the absorbing element, the first birefringent reflective polarizer having a first pass axis and a first block axis; and   a second birefringent reflective polarizer disposed on the second major surface of the absorbing element, the second reflective polarizer having a second pass axis and a second block axis;   wherein the first and second pass axes of the first and second reflective polarizers are substantially aligned;   wherein the absorbing element was coextruded with one or more of the reflective polarizers; and   wherein the absorbing element includes a thermally stable dye.   
     
     
         2 . The hybrid polarizer of  claim 1 , wherein each of the first birefringent reflective polarizer, the second birefringent reflective polarizer, and the absorbing element is nearly uniaxial. 
     
     
         3 . The hybrid polarizer of  claim 1 , wherein the first and second pass axes of the first and second reflective polarizers are aligned to within +/−1 degrees. 
     
     
         4 . The hybrid polarizer of  claim 1 , wherein the first and second pass axes of the first and second reflective polarizers are aligned to within +/−0.2 degrees. 
     
     
         5 . A display device, comprising a display panel and the hybrid polarizer of  claim 1 , where the second reflective polarizer is disposed closer to the display panel than the first reflective polarizer. 
     
     
         6 . The display device of  claim 5 , wherein the second reflective polarizer comprises a plurality of layers characterized by a varying optical thickness, and a majority of the layers having a smaller optical thickness are disposed closer to the display panel than the layers having a larger optical thickness.