Method and apparatus for fabrication of plastic fiber optic block materials and large flat panel displays

Abstract

This invention concerns a method and apparatus for manufacturing a sheet and a two-dimensional matrix of plastic optical fibers. The fibers may be of the step-index or graded-index type. Co-extrusion through a specially designed die is used to produce a sheet composed of a fiber array. The fiber sheet (ribbon) can be used for transmitting optical signals. These arrays may also be stacked and fused at high temperatures to form the two-dimensional matrix required for many applications such as large area image transfer. In addition, a high-speed, continuous manufacturing method is disclosed to produce a massive two-dimensional matrix of fibers. The method of manufacture permits high quality image transfer at low manufacturing cost in a wide array of geometries.

1 . A method for producing a block of optical fibers, comprising: 
 layering a plurality of m×N sheets of optical fibers, wherein m<<N;    causing the plurality of m×N sheets of optical fibers to form a block of optical fibers.    
   
   
       2 . The method of  claim 11 , wherein causing the plurality of m×N sheets to form a block of optical fibers comprises heating the plurality of m×N sheets above the glass transition temperature of the m×N sheets' material while applying pressure to the plurality of m×N sheets such that the m×N sheets fuse with each other.  
   
   
       3 . The method according to  claim 2 , wherein heating comprises heating the plurality of m×N sheets to a temperature in the range of about 20° C. above the glass transition temperature to about 60° C. above the glass transition temperature of the m×N sheet material.  
   
   
       4 . The method according to  claim 22 , further comprising: 
 drying the plurality of m×N sheets after layering.    
   
   
       5 . The method according to  claim 4 , wherein drying comprises heating the plurality of m×N sheets to a temperature below the glass transition temperature of the m×N sheets' material.  
   
   
       6 . The method according to  claim 5 , wherein drying comprises heating the plurality of m×N sheets to a temperature in the range of about 20° C. below the glass transition temperature to about 50° C. below the glass transition temperature of the m×N sheets' material.  
   
   
       7 . The method according to  claim 1 , wherein causing the plurality of m×N sheets of optical fibers to form a block of optical fibers comprises applying an adhesive between adjacent m×N sheets of optical fibers.  
   
   
       8 . The method according to  claim 7 , wherein the adhesive is set via a mechanism selected from the group consisting of: heat, ultraviolet radiation, oxygen activation, and pressure.  
   
   
       9 . The method according to  claim 8 , wherein pressure is exerted on the plurality of m×N sheets prior to setting the adhesive to remove air and water vapor from between the m×N sheets of optical fibers.  
   
   
       10 . The method according to  claim 1 , wherein 1≦m≦4.  
   
   
       11 . The method according to  claim 10 , wherein n≧100.  
   
   
       12 . The method according to  claim 10 , wherein n≧1000.  
   
   
       13 . The method according to  claim 13 , wherein layering a plurality of m×N sheets of optical fibers comprises: 
 winding a continuous m×N sheet of optical fibers onto a fixture such that the continuous m×N sheet of optical fibers layers upon itself as the continuous m×N sheet is wound onto the fixture; and cutting through the layers of the continuous m×N sheet wound onto the fixture in at least two locations such a layered plurality of m×N sheets of optical fibers is achieved.    
   
   
       14 . The method according to  claim 13 , wherein the fixture has a means for guiding the continuous m×N sheet onto the fixture such that each layer of the continuous m×N sheet is aligned with the previous layer of the continuous m×N sheet as the continuous m×N sheet is wound onto the fixture.  
   
   
       15 . The method according to  claim 13 , wherein pressure is applied to the layers of the continuous m×N sheet wound onto the fixture during to cutting.  
   
   
       16 . The method according to  claim 15 , wherein the means for guiding the continuous m×N sheet onto the fixture comprises two guides between which the continuous m×N sheet is guided, wherein pressure applied during cutting is applied via a cover plate which is positioned between the two guides and on top of the wound continuous m×N sheet.  
   
   
       17 . The method according to  claim 16 , wherein a distance separating the two guides between which the continuous m×N sheet is guided is maintained essentially equal to the width of the continuous m×N sheet and the width of the continuous m×N sheet is maintained at essentially a constant value during winding.  
   
   
       18 . The method of  claim 1 , wherein the m×N sheets of optical fibers are produced by the method of  claim 1 .  
   
   
       19 . The method of  claim 17 , wherein the m×N sheets of optical fibers are produced by the method of  claim 13 .  
   
   
       20 . A block of optical fibers produced in accordance with the method of  claim 19 .  
   
   
       21 . A display, comprising: 
 a plurality of display tiles, each having a light-emissive display area surrounded by a non-light emissive border wherein at least two of the plurality of display tiles are positioned adjacent each other such that the borders of adjacent tiles are adjacent each other and create a non-light emissive seam between the adjacent tiles; and a corresponding plurality of polymeric fiber optic image transmission devices, a first end of each image transmission device coupled to the display area of the corresponding display tile, and a second end of each image transmission device being in lateral contact with a second end of the image transmission devices corresponding to display tiles adjacent its corresponding display tile,    wherein the image transmission devices each comprise an array of optical fibers, each optical fiber having a first end at the first end of the image transmission device and a second end at the second end of the image transmission device, wherein each of the plurality of image transmission devices conveys an image received by its first end from its corresponding display tile to its second end such that the second ends of the plurality of image transmission devices act as a single secondary display panel, wherein the size of the seam between the second ends of adjacent image transmission devices is smaller than the seam between the corresponding adjacent display tiles.    
   
   
       22 . The display according to  claim 21 , wherein the seam between the second ends of adjacent image transmission devices is essentially imperceptible.  
   
   
       23 . The display according to  claim 21 , wherein the image transmission devices are produced from a block of optical fibers produced by the method of  claim 21 .  
   
   
       24 . The display according to  claim 21 , wherein the image transmission devices are produced from a block of optical fibers produced by the method of claim  39 .  
   
   
       25 . The display according to  claim 21 , further comprising a light diffuser sheet optically coupled to the single secondary display panel.