Optically transmissive substrates and light emitting assemblies and methods of making same, and methods of displaying images using the optically transmissive substrates and light emitting assemblies

Abstract

Images are displayed in response to a video signal using a light emitting assembly having one or more optically transmissive substrates, films or sheets, each having at least one pattern of optical elements on or in the substrates, films or sheets. A plurality of light sources are configured to illuminate one or more output areas of one or more of the substrates, films or sheets. The light emitting assembly is configured to emit light through the pattern of optical elements and produce a predetermined luminance profile of the light emitting assembly. At least some adjacent substrates, films or sheets may have portions that overlap, and at least one pattern of optical elements on or in at least one side of the substrates, films or sheets may be configured so that discontinuities between the adjacent substrates, films or sheets are minimized.

1 . A light emitting assembly comprising:
 a plurality of optically transmissive substrates, films, or sheets;   the substrates, films, or sheets having an edge portion adjacent an edge portion of an adjacent substrate, film, or sheet;   a plurality of light sources, each light source being configured to emit light into at least one area of the substrates, films, or sheets; and   at least one pattern of optical elements at at least one side of the substrates, films, or sheets, wherein the optical elements are substantially smaller than the length and width of the substrates, films, or sheets, and the optical elements of the respective patterns at the adjacent substrates, films, or sheets adjacent seams between the adjacent edge portions of the adjacent substrates, films or sheets have shapes that substantially match one another to form substantially seamless transitions with minimal discontinuities in the optical element shapes at the seams to make the seams less visible.   
     
     
         2 . The light emitting assembly of  claim 1 , wherein at least two of the adjacent substrates, films, or sheets each have a tapered cross sectional profile, and at least one light source is positioned near a thicker end of each of the at least two adjacent substrates, films, or sheets, and a thinner end of one of the at least two adjacent substrates, films, or sheets extends over the light source and the thicker end of the other of the at least two adjacent substrates, films, or sheets; and
 wherein the edge portion of the one adjacent substrate, film, or sheet is at the thinner end of the one adjacent substrate, film, or sheet, and the edge portion of the other adjacent substrate, film, or sheet is at an inner end of a recess in the thicker end of the other adjacent substrate, film, or sheet in which the thinner end of the one adjacent substrate, film, or sheet is received.   
     
     
         3 . The light emitting assembly of  claim 2 , wherein the light sources are side emitting light emitting diodes. 
     
     
         4 . A method of controlling the light output distribution of a light emitting assembly including a plurality of optically transmissive substrates, films, or sheets, wherein each of the substrates, films, or sheets has at least one pattern of optical elements on or in the substrates, films, or sheets, and a plurality of light sources, each light source being configured to emit light into at least one area of the substrates, films, or sheets, comprising the step of:
 varying the electrical input to at least some of the light sources to produce a predetermined light output from the light emitting assembly, wherein an edge portion of at least one of the substrates, films, or sheets is adjacent an edge portion of an other of the substrates, films, or sheets, the optical elements are substantially smaller than the length and width of the substrates, films, or sheets, and the optical elements of the respective patterns at the one and the other substrates, films, or sheets adjacent a seam between the adjacent edge portions have shapes that substantially match one another to form a substantially seamless transition with minimal discontinuities in the optical element shapes at the seam to make the seam less visible.   
     
     
         5 . The method of  claim 4 , wherein the light sources are light emitting diodes. 
     
     
         6 . The method of  claim 4 , wherein the light output distribution from the light emitting assembly is substantially uniform. 
     
     
         7 . The lighting assembly of  claim 1 , wherein the edge portion of the other adjacent substrate, film, or sheet is at an inner end of a recess in an end of the other adjacent substrate, film, or sheet, and the edge portion of the one adjacent substrate, film, or sheet is at an end of the one adjacent substrate, film, or sheet that is received in the recess in the end of the other adjacent substrate, film, or sheet. 
     
     
         8 . The method of  claim 4 , wherein the edge portion of the other substrate, film, or sheet is at an inner end of a recess in an end of the other substrate, film, or sheet, and the edge portion of the one substrate, film, or sheet is at an end of the one substrate, film, or sheet that is received in the recess in the end of the other substrate, film, or sheet.