Anti-reflective thin film constructions

Abstract

A broadband anti-reflective thin film article is disclosed. The articles includes a base substrate having a substrate surface and a thin film polymeric multi-layer anti-reflectivity stack having a plurality of polymer layers. Each polymer layer having a thickness no greater than 1 micrometer. The substrate surface has a broadband reflectivity value. The thin film polymeric multi-layer anti-reflectivity stack is optically coupled to the substrate surface. The thin film polymeric multi-layer anti-reflectivity stack reduces the broadband reflectivity of the substrate surface by a factor of at least 2 at normal angles of incidence.

1 . A broadband anti-reflective article comprising; 
 a base substrate having a substrate surface, the substrate surface having a broadband reflectivity value;    a thin film polymeric multi-layer anti-reflectivity stack comprising a plurality of polymer layers, each of the polymer layers having a thickness no greater than about 1 micrometer, the thin film polymeric multi-layer anti-reflectivity stack is optically coupled to the substrate surface;    wherein, the thin film polymeric multi-layer anti-reflectivity stack reduces the broadband reflectivity of the substrate surface by a factor of at least 2 at normal angles of incidence.    
   
   
       2 . An article according to  claim 1  wherein the thin film polymeric multi-layer anti-reflectivity stack reduces visible light broadband spectrum reflectivity of the substrate surface by a factor of at least 2 at normal angles of incidence.  
   
   
       3 . An article according to  claim 1  wherein the thin film polymeric multi-layer anti-reflectivity stack reduces a broadband light spectrum from 420 nm to 750 nm reflectivity of the substrate surface by a factor of at least 2 at normal angles of incidence.  
   
   
       4 . An article according to  claim 1  wherein the base has an index of refraction of about 1.5.  
   
   
       5 . An article according to  claim 1  wherein the plurality of polymer layers comprises a low index polymer layer selected from the group consisting of silicone polymers and fluoropolymers, and combinations thereof.  
   
   
       6 . An article according to  claim 1  where the plurality of polymer layers comprises a high index polymer layer selected from the group consisting of polyethylene naphthalate, polyethylene terephthalate, and copolymers thereof.  
   
   
       7 . An article according to  claim 1  wherein the plurality of polymer layers comprises a low index polymer layer selected from the group consisting of silicone polymers and fluoropolymers, and combinations thereof and the plurality of polymer layers comprises a high index polymer layer selected from the group consisting of polyethylene naphthalate, polyethylene terephthalate, and copolymers thereof.  
   
   
       8 . An article according to  claim 1  wherein each polymer layer has an optical thickness in a range from 1/16 to 1 wavelength.  
   
   
       9 . An article according to  claim 1  wherein each polymer layer has a thickness in a range from 10 to 250 nm.  
   
   
       10 . A broadband anti-reflective article comprising; 
 a base substrate having a substrate surface, the substrate surface having a broadband reflectivity value measured in air of 6% or greater, at normal angles of incidence;    a thin film polymeric multi-layer anti-reflectivity stack comprising a plurality of polymer layers, each of said polymer layers having a thickness no greater than about 1 micrometer, the thin film polymeric multi-layer anti-reflectivity stack optically coupled to the substrate surface;    wherein, the thin film polymeric multi-layer anti-reflectivity stack reduces the broadband reflectivity value measured in air to a value of less than 6%, at normal angles of incidence.    
   
   
       11 . An article according to  claim 10  wherein the thin film polymeric multi-layer anti-reflectivity stack reduces visible light broadband spectrum reflectivity value measured in air to a value of less than 3%, at normal angles of incidence.  
   
   
       12 . An article according to  claim 10  wherein the thin film polymeric multi-layer anti-reflectivity stack reduces a broadband light spectrum from 420 nm to 750 nm reflectivity value measured in air to a value of less than 3%, at normal angles of incidence.  
   
   
       13 . An article according to  claim 10  wherein the thin film polymeric multi-layer anti-reflectivity stack reduces a broadband light spectrum from 420 nm to 750 nm reflectivity value measured in air to a value of less than 1%, at normal angles of incidence.  
   
   
       14 . An article according to  claim 10  wherein the base has an index of refraction of about 1.5.  
   
   
       15 . An article according to  claim 10  wherein the plurality of polymer layers comprises a low index polymer layer selected from the group consisting of silicone polymers and fluoropolymers, and combinations thereof.  
   
   
       16 . An article according to  claim 10  where the plurality of polymer layers comprises a high index polymer layer selected from the group consisting of polyethylene naphthalate, polyethylene terephthalate, and copolymers thereof.  
   
   
       17 . An article according to  claim 10  wherein the plurality of polymer layers comprises a low index polymer layer selected from the group consisting of silicone polymers and fluoropolymers, and combinations thereof and the plurality of polymer layers comprises a high index polymer layer selected from the group consisting of polyethylene naphthalate, polyethylene terephthalate, and copolymers thereof.  
   
   
       18 . An article according to  claim 10  wherein each polymer layer has an optical thickness in a range from 1/16 to 1 wavelength.  
   
   
       19 . An article according to  claim 10  wherein each polymer layer has a thickness in a range from 10 to 250 nm.