Color Liquid Crystal Displays and Display Backlights

Abstract

A display backlight, comprises: an excitation source, LED (146), for generating blue excitation light (148) with a peak emission wavelength in a wavelength range 445 nm to 465 nm; and a photoluminescence wavelength conversion layer (152). The photoluminescence wavelength conversion layer (152) comprises a mixture of a green-emitting photoluminescence material with a peak emission in a wavelength range 530 nm to 545 nm, a red-emitting photoluminescence material with a peak emission in a wavelength range 600 nm to 650 nm and particles of light scattering material.

What is claimed is: 
     
         1 . (canceled) 
     
     
         2 . A display backlight, comprising:
 a source for generating light with a wavelength of maximum intensity from 445 nm to 465 nm; and   a multi-layer film comprising:
 a brightness enhancement film layer; and 
 a phosphor film layer in direct contact with the brightness enhancement film layer; 
 wherein the phosphor film layer comprises a light transmissive material, a narrow-band green phosphor, and narrowband-red phosphor, and 
 wherein the narrowband-red phosphor is at least one selected from the group consisting of: K 2 SiF 6 :Mn 4+ , K 2 TiF 6 :Mn 4+ , CaSeS:Eu, and MSe 1-x S x :Eu where M is at least one of Mg, Ca, Sr, and Ba. 
   
     
     
         3 . The backlight of  claim 2 , wherein the narrow-band red phosphor is for generating light with a wavelength of maximum intensity from 600 nm to 650 nm. 
     
     
         4 . The backlight of  claim 2 , wherein the narrow-band green phosphor is for generating light with a wavelength of maximum intensity from 530 nm to 545. 
     
     
         5 . The backlight of  claim 2 , wherein the narrow-band green phosphor is at least one selected from the group consisting of: SrGa 2 S 4 :Eu, and β-SiAlON. 
     
     
         6 . The backlight of  claim 2 , wherein the phosphor film layer is fabricated directly onto the brightness enhancement film layer. 
     
     
         7 . The backlight of  claim 2 , wherein the phosphor film layer and brightness enhancement film layer are fabricated separately. 
     
     
         8 . A display backlight, comprising:
 a source for generating light with a wavelength of maximum intensity from 445 nm to 465 nm; and   a multi-layer film comprising:
 a light diffusive film layer; and 
 a phosphor film layer in direct contact with the light diffusive film layer; 
 wherein the phosphor film layer comprises a light transmissive material, a narrow-band green phosphor, and narrowband-red phosphor, and 
 wherein the narrowband-red phosphor is at least one selected from the group consisting of: K 2 SiF 6 :Mn 4+ , K 2 TiF 6 :Mn 4+ , CaSeS:Eu, and MSe 1-x S x :Eu where M is at least one of Mg, Ca, Sr, and Ba. 
   
     
     
         9 . The backlight of  claim 8 , wherein the narrow-band red phosphor is for generating light with a wavelength of maximum intensity from 600 nm to 650 nm. 
     
     
         10 . The backlight of  claim 8 , wherein the narrow-band green phosphor is for generating light with a wavelength of maximum intensity from 530 nm to 545. 
     
     
         11 . The backlight of  claim 8 , wherein the narrow-band green phosphor is at least one selected from the group consisting of: SrGa 2 S 4 :Eu, and β-SiAlON. 
     
     
         12 . The backlight of  claim 8 , wherein the phosphor film layer is fabricated directly onto the light dissuasive film layer. 
     
     
         13 . The backlight of  claim 8 , wherein the phosphor film layer and light diffusive film layer are fabricated separately.