Patterned platelets

Abstract

Patterned platelets are platelets made with specified shapes and sizes. The various sizes and shapes of the platelets are used to code articles and substances to which they are applied. The patterned platelets can be in inks or paints applied to articles. The platelets can be further coded by markings thereon or by spectral or polarization codes rather than just the distribution of sizes and shapes. The patterned platelets can be made from any materials buy subtractive or additive processes. A patterned platelet can also be made by an actinic polymer being applied to a substrate and a mask applied to allow only the desired size and shape to be exposed to radiation curing the unmasked portion of the polymer on the substrate. The polymer can be cholesteric liquid crystals with the properties of reflecting polarized light of selected wavelengths to code the crystals in addition to the size and shape codes. The cholesteric liquid crystals may also be doped with materials which absorb a portion of the wavelengths which would otherwise be reflected further coding the patterned platelets. Codes of the patterned platelets can be composed of the distribution of the platelets alone or in combination with the position of the platelets on an object. A code with the presence or absence of a specified patterned platelet in a specified location could be a binary code. If n different patterned platelets are used in each of x positions a code with x to the nth power combinations is possible.

1 . A coded patterned platelet comprising: 
 a platelet having a specified shape, a specified surface area and one or more specified identification markings thereon.    
   
   
       2 . A coded patterned platelet as in  claim 1  wherein: 
 one or more specified identification markings are selected from the group consisting of spatial markings, spectral markings, or polarization markings on the coded patterned platelet.    
   
   
       3 . A coded patterned platelet as in  claim 2  wherem: 
 one or more spatial markings are selected from the group consisting of geometric shapes, numbers, letters, irregular shapes, notches, and apertures.    
   
   
       4 . A coded patterned platelet as in  claim 2  wherein: 
 one or more spectral markings are produced by materials selected from the group consisting of dyes, pigments, Cholerestic Liquid Crystals, doped Cholerestic Liquid Crystals materials, holographic materials, refractive materials, reflective materials, and metallic materials.    
   
   
       5 . A patterned platelet identity code for use with articles or substances comprising: 
 a plurality of patterned platelets having any combination of n specified shapes with m specified surface areas where n and m are any integers with a value 1 or greater.    
   
   
       6 . A patterned platelet identity code for use with articles or substances as in  claim 5  wherein: 
 the identity code is further defined by one or more markers selected from the group consisting of the percentage distribution of n sizes and m shapes of patterned platelets, spectral codes, polarization codes, spatial codes position on the article codes and angle of observation codes.    
   
   
       7 . A method of making polymer patterned platelets comprising: 
 preparing a mixture of polymer material to be actinically cured,    spreading a layer of the of polymer material to be actinically cured on a sheet of substrate material,    applying a mask with apertures of the shapes and sizes of the desired patterned platelets to the poloymer material to be actinically cured,    exposing the masked polymer material to be actinically cured to radiation, thus forming patterned platelets of a specified shape and size,    removing the patterned platelets from the substrate.    
   
   
       8 . A method of making polymer patterned platelets as in  claim 7  wherein, 
 the polymer is a cholesteric liquid crystal.    
   
   
       9 . A method of making. cholesteric liquid crystal patterned platelets as in  claim 8  wherein there is the additional step of: 
 varying the concentration of chiral dopants for controlling the pitch of the cholesteric liquid crystal material such that it reflects a specified portion the spectrum.    
   
   
       10 . A method of making cholesteric liquid crystal patterned platelets as in  claim 8  wherein there is the additional step of: 
 doping the cholesteric liquid crystal material to absorb a specified portion the spectrum.    
   
   
       11 . A method of making cholesteric liquid crystal patterned platelets as in  claim 9  wherein there is the additional step of: 
 spatially marking the cholesteric liquid crystal material.    
   
   
       12 . A method of making cholesteric liquid crystal patterned platelets as in  claim 8  wherein there is the additional step of: 
 repeating the process steps of spreading a layer of the of cholesteric liquid crystal material to be actinically cured on a sheet of substrate material,    applying a mask with apertures of the shapes and sizes of the desired patterned platelets to the cholesteric liquid crystal material to be actinically cured,    exposing the masked cholesteric liquid crystal material to be actinically cured to radiation, thus forming patterned platelets of a specified shape and size,    to obtain successive layers of cholesteric liquid crystal material.    
   
   
       13 . A method of making cholesteric liquid crystal patterned platelets as in claim wherein the masks are changed to add spatial markings.  
   
   
       14 . A method of making cholesteric liquid crystal patterned platelets as in  claim 12  wherein the masks are changed to create three-dimensional shapes.  
   
   
       15 . A method of making patterned platelets comprising: 
 masking an area of a substrate to obtain a shape and size for the patterned platelet,    depositing a layer of material through the mask,    removing the patterned platelets from the substrate.    
   
   
       16 . A method of making patterned platelets as in  claim 15  wherein: 
 the additional steps of masking an area of the material previously deposited, and depositing a layer of material through the mask to add to the previously deposited material.    
   
   
       17 . A method of making patterned platelets as in  claim 15  wherein: 
 the additional steps of masking an area of the material previously deposited, and depositing a layer of a different material through the mask to add to the previously deposited material.    
   
   
       18 . A method of making patterned platelets as in  claim 15  wherein: 
 the additional steps of masking a portion of the area of the material previously deposited, and depositing a layer of material through the mask to add to the previously deposited material and define a spatial marking thereon.    
   
   
       19 . A method of making patterned platelets as in  claim 15  wherein: 
 the additional steps of masking a portion of the area of the material previously deposited, and depositing a layer of material through the mask to add to the previously deposited material and add material to make a three-dimensional shaped patterned platelet.    
   
   
       20 . A method of making patterned platelets as in  claim 15  wherein: 
 the additional steps of masking a portion of the area of the material previously deposited, and subtracting a layer of material from the unmasked portion of the previously deposited material to define a spatial marking thereon.    
   
   
       21 . A method of making patterned platelets comprising: 
 forming a film of material on a substrate,    masking a portion of the film,    removing material from the unmasked portion of the material, to form patterned platelets,    removing the patterned platelets from the substrate.    
   
   
       22 . A method of making patterned platelets as in  claim 21  wherein: 
 the additional steps of masking a portion of the area of the material, and subtracting a layer of material from the unmasked portion of the patterned platelet material to define a spatial marking thereon.    
   
   
       23 . A method of detecting patterned platelet codes comprising the steps of: 
 observing a sample of the coded patterned platelets,    counting the patterned platelets by type used to determine if it fits the code pattern.    
   
   
       24 . A method of detecting patterned platelet codes as in  claim 23  wherein, 
 a charge coupled device pixelizes the image of the patterned platelets observed,    the charge coupled device sends the image of the platelets to a computer programmed with pattern recognition software to recognize and count the shapes and sizes and spatial markings of the patterned platelets used and compare it to the code used.    
   
   
       25 . A method of detecting patterned platelet codes as in  claim 23  wherein a spectrum analyzer determines the spectral codes uses.  
   
   
       26 . A method of detecting patterned platelet codes as in  claim 23  wherein a polarization detector detects the polarization codes used.  
   
   
       27 . A code comprising patterned platelets.  
   
   
       28 . A code as in  claim 27  wherein, 
 the code comprises one or more features of the patterned platelets chosen from the group consisting of specified shapes, specified sizes, spatial markings, percentage distributions of coded patterned platelets, spectral markings, polarization markings and angle of viewing codes.    
   
   
       29 . A code as in  claim 27  wherein, 
 the positions of the patterned platelets relative to each other on an article are part of the code.    
   
   
       30 . A code as in  claim 29  wherein, 
 the code comprises one or more features of the patterned platelets chosen from the group consisting of blank spaces, specified shapes, specified sizes, spatial markings, percentage distributions of coded patterned platelets, spectral markings, polarization markings and angle of viewing codes.    
   
   
       31 . An coded ink comprising: 
 an ink carrier,    a code of a plurality of coded patterned pigments in the ink carrier.    
   
   
       32 . A coded paint comprising: 
 a paint carrier,    a code of a plurality of patterned pigments in the paint carrier.    
   
   
       33 . A coded paint as in  claim 32  wherein the paint is applied to an article to code the article.  
   
   
       34 . A coded ink as in  claim 31  wherein the ink is applied to an article to code the article.  
   
   
       35 . A code as in  claim 27  wherein: 
 the patterned platelets are applied to the surface of an article to identify it.    
   
   
       36 . A code as in  claim 27  wherein: 
 the patterned platelets are mixed in with the material comprising an article to identify it.    
   
   
       37 . A code as in  claim 27  wherein: 
 the patterned platelets are mixed in with a liquid to identify it.