Optical body including multilayer optical film and thin adhesive layer

Abstract

Optical bodies are described. In particular, optical bodies having a birefringent multilayer optical film and a continuous adhesive layer with a thickness less than 20 micrometers are described. Optical bodies described herein exhibit reduced occurrence and severity of a non-uniformity defect known as “orange peel.”

What is claimed is: 
     
         1 . An optical body, comprising:
 a birefringent multilayer optical film;   a continuous adhesive layer disposed on a first major surface of the birefringent multilayer optical film; and   a polymeric liner disposed on the continuous adhesive layer;   wherein the continuous adhesive layer has a thickness less than 20 micrometers and includes an adhesive derived from a solution having a viscosity between 10 and 50,000 cps.   
     
     
         2 . The optical body of  claim 1 , further comprising a hardcoat layer on the birefringent multilayer optical film on a second major surface opposite the first major surface. 
     
     
         3 . The optical body of  claim 1 , wherein the birefringent multilayer optical film is thicker than 35 micrometers. 
     
     
         4 . The optical body of  claim 1 , wherein the birefringent multilayer optical film includes at least two optical packets, wherein the at least two optical packets have thicknesses that overlap by at least 80%. 
     
     
         5 . The optical body of  claim 1 , wherein the adhesive of the continuous adhesive layer includes an acrylate adhesive. 
     
     
         6 . An optical body, comprising:
 a birefringent multilayer optical film;   a continuous adhesive layer disposed on a first major surface of the birefringent multilayer optical film; and   a glass or plastic substrate layer attached to the multilayer optical film via the continuous adhesive layer;   wherein the continuous adhesive layer has a thickness less than 20 micrometers; and   wherein the optical body, measured through the glass or plastic substrate layer with an interferometer, has an Ra surface roughness of less than 40 nm.   
     
     
         7 . The optical body of  claim 6 , further comprising a hardcoat layer on the birefringent multilayer optical film on a second major surface opposite the first major surface. 
     
     
         8 . A projection system, comprising:
 a projection engine having a light projection path; and   the optical body of  claim 6 ;   wherein the light projection path includes passing through or bouncing off the optical body.   
     
     
         9 . A method of providing an optically smooth laminated optical body, the method comprising:
 providing a birefringent multilayer optical film coated with a continuous adhesive layer having a thickness less than 20 micrometers and having a polymeric liner disposed on the continuous adhesive layer;   removing the polymeric liner;   attaching the birefringent multilayer optical film and the continuous adhesive layer to a glass or plastic substrate layer to form an optically smooth laminated optical body;   wherein the optically smooth laminated optical body, measured through the glass or plastic substrate layer with an interferometer, has an Ra surface roughness of less than 40 nm.   
     
     
         10 . The method of  claim 9 , further comprising the step of curing the continuous adhesive layer.