Color Laser Engraving

Abstract

The present disclosure relates generally to color laser engraving. One claim recites a method of color laser exposing a document, the document comprising a multi-layer structure including a surface layer and one or more sub-layers, the one or more sub-layers including coloring, said method comprising: receiving the document; and selectively providing openings in the surface layer with a laser to expose one or more of the sub-layers, wherein the coloring is perceptible through the openings, and in which the coloring comprises a plurality of different colors arranged in a grouping, with the one or more sub-layers comprising repeated instances of the grouping. Of course, other claims are provided too.

1 . A method of color laser exposing a document, the document comprising a multi-layer structure including a surface layer and one or more sub-layers, the one or more sub-layers including coloring, said method comprising:
 receiving the document; and   selectively providing openings in the surface layer with a laser to expose one or more of the sub-layers, wherein the coloring is perceptible through the openings, and   in which the coloring comprises a plurality of different colors arranged in a grouping, with the one or more sub-layers comprising repeated instances of the grouping.   
     
     
         2 . The method of  claim 1  in which the plurality of different colors comprise cyan, magenta and yellow. 
     
     
         3 . The method of  claim 2  in which the plurality of different colors further comprise black. 
     
     
         4 . The method of  claim 3  in which the plurality of different colors comprises ink, pigment or dye. 
     
     
         5 . The method of  claim 1  in which the grouping comprises the plurality of different colors arranged in a generally circular grouping. 
     
     
         6 . The method of  claim 5  in which the coloring is perceptible through at least three openings per grouping. 
     
     
         7 . The method of  claim 1  in which the grouping comprises the plurality of different colors arranged in a linear manner. 
     
     
         8 . The method of  claim 7  in which the coloring is perceptible through at least three openings per grouping. 
     
     
         9 . The method of  claim 1  in which the grouping comprises an overlapping arrangement of the plurality of different colors. 
     
     
         10 . The method of  claim 9  in which the grouping requires only one opening per pixel to achieve a predetermined color. 
     
     
         11 . A method of color laser exposing a document, the document comprising a multi-layer structure including a surface layer and one or more sub-layers, the one or more sub-layers including coloring, said method comprising:
 receiving the document; and   selectively providing openings in the surface layer with a laser to expose one or more of the sub-layers, wherein the coloring is perceptible through the openings, and   in which the one or more sub-layers comprise at least a first sub-layer and a second sub-layer, with the first sub-layer and the second sub-layer being adjacently arranged, and wherein the first sub-layer comprises a first coloring and the second sub-layer comprises a second, different coloring.   
     
     
         12 . The method of  claim 11  in which the second coloring is perceptible through the openings in the surface layer when the openings extend through the first sub-layer. 
     
     
         13 . The method of  claim 11  in which the one or more sub-layers further comprise a third sub-layer. 
     
     
         14 . The method of  claim 13  in which the first sub-layer, the second sub-layer and the third sub-layer each comprise one of cyan, magenta and yellow. 
     
     
         15 . The method of  claim 11  in which selectively providing openings in the surface layer with a laser to expose one or more of the sub-layers exposes at least the first coloring of the first sub-layer and the second coloring of the second sub-layer, and wherein the opening is tapered to expose more of the first coloring relative to the second coloring. 
     
     
         16 . The method of  claim 15  in which the tapered opening provides a human perceptible bull's-eye pattern. 
     
     
         17 . The method of  claim 11  in which the laser is moved in directions both parallel and perpendicular to a surface of the document, the laser being movable in distance segments parallel to the document surface that correspond to sub-pixel and pixel sizes in the one or more sub-layers and distance segments perpendicular to the document surface that correspond to a thickness of the one or more sub-layers, and wherein an appropriate color is selected based upon a distance from the surface of the document and a portion of the laser, and intensity of a color channel is used to select power sent to the laser. 
     
     
         18 . The method of  claim 11  in which the laser is only moved in directions parallel to a surface of the document, with a color being selected based upon laser power, and intensity of the color is used to select a number of openings the laser opens for each pixel. 
     
     
         19 . An identification document comprising:
 a sub-layer including a plurality of inks arranged in a grouping, wherein the sub-layer comprises repeated instances of the grouping; and   a surface layer adjacently arranged with the sub-layer, wherein the surface layer obscures at least a majority of the repeated instances of the grouping; and   wherein the identification document further comprises a plurality of openings in the surface layer, wherein at least some portions of some of the repeated instances of the grouping are perceptible through the plurality of openings to convey an image or text.   
     
     
         20 . The identification document of  claim 19  in which a plural-bit machine-readable code is detectable through the openings. 
     
     
         21 . The identification document of  claim 19  in which the openings result from laser engraving.