Apparatus for selectively backlighting a material

Abstract

A backlighting device ( 300, 400, 500, 600 ) emitting light having a first wavelength includes a first radiation emission device ( 302 ), e.g., an electroluminescent lamp, for emitting radiation having a second wavelength. A layer ( 306 ) of a plurality of photon emitting particles ( 308 ), e.g., free standing quantum dots or phosphorus particles, emits light having the first wavelength in response to the first radiation emission device ( 302 ), the first wavelength being larger than the second wavelength. A transparent material ( 116, 120, 122 ) overlies the layer of a plurality of photon emitting particles ( 308 ), wherein the light having a first wavelength passes through the transparent material ( 116, 120, 122 ). Optionally, a filter ( 402 ) may be placed over the layer ( 306 ) to block the radiation having a second wavelength, and a scattering layer ( 604 ) may be placed over the layer ( 306 ) to scatter wavelength other than the first wavelength.

1 - 22 . (canceled) 
     
     
         23 . A backlighting device for emitting light including a first wavelength, comprising:
 an electroluminescent lamp for emitting radiation having a second wavelength; and a layer of a plurality of photon emitting particles comprising free standing quantum dots emitting light having the first wavelength in response to the radiation from the electroluminescent lamp, the first wavelength being larger than the second wavelength, and   a layer including scattering particles disposed over the layer of a plurality of photon emitting particles that scatters the radiation from the electroluminescent lamp, wherein the scattering particles have diameters equal to or smaller than the scattered radiation wavelength.   
     
     
         24 . The backlighting device of  claim 23  wherein the scattering particles scatter radiation of the second wavelength with a higher scattering coefficient than that of the first wavelength. 
     
     
         25 . The backlighting device of  claim 23  further comprising a filter disposed over the layer of free standing quantum dots that prevents the radiation having a second wavelength from passing through while allowing the light having a first wavelength to pass through. 
     
     
         26 . The backlighting device of  claim 23  further comprising a transparent material overlying the layer of quantum dots. 
     
     
         27 . The backlighting device of  claim 23  further comprising further comprising a transparent material overlying the layer of free standing quantum dots wherein the transparent material comprises one of a touch key, an icon, and at least a portion of a housing of an electronic device. 
     
     
         28 . The backlighting device of  claim 23  wherein the layer of free standing quantum dots further comprises another other photon emitting material. 
     
     
         29 . The backlighting device of  claim 23  further including a radiation emission device disposed on a side of the electroluminescent lamp opposed to the layer of free standing quantum dots. 
     
     
         30 . A backlighting device emitting light including a first wavelength, comprising:
 au electroluminescent lamp for emitting radiation having a second wavelength,   a layer including a plurality of free standing quantum dots including first free standing quantum dots emitting light having the first wavelength in response to being impacted by the radiation having a second wavelength, the first wavelength being larger than the second wavelength, and one or more other free standing quantum dots emitting light in response being impacted by the radiation having a second wavelength, the one or more other free standing quantum dots emitting light at one or more other wavelengths different from the first and second wavelengths; and   a layer including scattering particles disposed over the layer of free standing quantum dots that scatters the radiation having a second wavelength, wherein the scattering particles have diameter equal to or smaller than the scattered radiation wavelength.   
     
     
         31 . The backlighting device of  claim 30  wherein the scattering particles scatter radiation of the second wavelength with a higher scattering coefficient than that of the first wavelength. 
     
     
         32 . The backlighting device of  claim 30  further including a radiation emission device disposed on a side of the electroluminescent lamp opposed to the layer of free standing quantum dots. 
     
     
         33 . The backlighting device of  claim 30  further comprising a filter disposed over the layer of free standing quantum dots that prevents the radiation having a second wavelength from passing through while allowing the light having a first wavelength to pass through. 
     
     
         34 . The backlighting device of  claim 30  further comprising a transparent material overlying the layer of quantum dots. 
     
     
         35 . The backlighting device of  claim 30  further comprising further comprising a transparent material overlying the layer of free standing quantum dots wherein the transparent material comprises one of a touch key, an icon, and at least a portion of a housing of an electronic device. 
     
     
         36 . The backlighting device of  claim 30  wherein the layer of free standing quantum dots further comprises another other photon emitting material. 
     
     
         37 . The backlighting device of  claim 30  wherein the scattering particles scatter radiation of the second wavelength with a higher scattering coefficient than that of the first wavelength and that of any different wavelengths emitted by the one or more other free standing quantum dots.