Antiscattering grid and a method of manufacturing such a grid

Abstract

An antiscattering grid for an X-ray imaging apparatus of the type comprising a substrate having a plurality of metallized partitions which together define a plurality of cells distributed over the substrate. The partitions allow passage of the X-rays emitted from a source lying in line with the grid, and absorbing the X-rays not coming directly from this source. The substrate is made of a polymer material that may be formed by radiation curing of a monomer sensitive to this radiation. The substrate may be substantially planar and the partitions may be oriented to form a focused grid.

1 . An antiscattering grid for emitted radiation comprising: 
 a substrate of a polymer material having a plurality of metallized polymer partitions that define a plurality of cells distributed over the substrate;    the partitions allowing passage of the emitted radiation from a source lying in line with the grid; and    the partitions disposed for absorbing the radiation not coming directly from the source.    
   
   
       2 . The grid according to  claim 1  wherein the substrate is made from a photocurable resin.  
   
   
       3 . The grid according to  claim 1  wherein external upper and lower surfaces of the substrate are not metallized.  
   
   
       4 . The grid according to  claim 2  wherein external upper and lower surfaces of the substrate are not metallized.  
   
   
       5 . The grid according to  claim 1  wherein the substrate has a substantially planar shape.  
   
   
       6 . The grid according to  claim 3  wherein the substrate has a substantially planar shape.  
   
   
       7 . The grid according to  claim 1  wherein the partitions are oriented to form a focused grid.  
   
   
       8 . The grid according to  claim 5  wherein the partitions are oriented to form a focused grid.  
   
   
       9 . The grid according to  claim 1  wherein the cells are filled with a polymer.  
   
   
       10 . The grid according to  claim 2  wherein the cells are filled with a polymer.  
   
   
       11 . The grid according to  claim 3  wherein the cells are filled with a polymer.  
   
   
       12 . The grid according to  claim 5  wherein the cells are filled with a polymer.  
   
   
       13 . The grid according to  claim 7  wherein the cells are filled with a polymer.  
   
   
       14 . The grid according to  claim 1  wherein the cells have an opening equal to or greater than about 200 μm and equal to or less than about 300 μm and the partitions have a thickness equal to or greater than about 50 μand equal to or less than about 100 μm.  
   
   
       15 . The grid according to  claim 1  wherein the cells have a pitch equal to or greater than about 50 μm and equal to or less than about 100 μm and partitions having a thickness of equal to or greater than about 20 μm and equal to or less than about 50 μm.  
   
   
       16 . The grid according to  claim 1  wherein the grid is disposed in an X-ray imaging apparatus that includes a detector and the grid has a pitch equal to the period of the detector.  
   
   
       17 . The grid according to  claim 1  wherein the ratio of the grid thickness to the distance between partitions is a ratio of greater than 8.  
   
   
       18 . The grid according to  claim 2  wherein the ratio of the grid thickness to the distance between partitions is a ratio of greater than 8.  
   
   
       19 . The grid according to  claim 3  wherein the ratio of the grid thickness to the distance between partitions is a ratio of greater than 8.  
   
   
       20 . The grid according to  claim 5  wherein the ratio of the grid thickness to the distance between partitions is a ratio of greater than 8.  
   
   
       21 . The grid according to  claim 7  wherein the ratio of the grid thickness to the distance between partitions is a ratio of greater than 8.  
   
   
       22 . The grid according to  claim 9  wherein the ratio of the grid thickness to the distance between partitions is a ratio of greater than 8.  
   
   
       23 . The grid according to  claim 16  wherein the ratio of the grid thickness to the distance between partitions is a ratio of greater than 8.  
   
   
       24 . The grid according to  claim 1  wherein the cells have a shape of a parallelogram.  
   
   
       25 . The grid according to  claim 1  wherein the metallization of the partitions comprises at least one layer formed by a metal selected from gold, copper, tantalum and lead.  
   
   
       26 . The grid according to  claim 25  wherein the metallization comprises several layers, each layer being formed from a metal selected from gold, copper, tantalum and lead.  
   
   
       27 . The grid according  claim 12  wherein the metallization has a thickness of a few micrometers.  
   
   
       28 . The grid according to  claim 1  wherein the substrate is formed of a material having a density and an atomic number that is low enough to have low absorption of the emitted radiation.  
   
   
       29 . The grid according to  claim 1  wherein the substrate is formed of a monomer resin sensitive to radiation, the monomer resin selected from epoxy and acrylic.  
   
   
       30 . The grid according to  claim 1  wherein the substrate has a thickness that is not constant.  
   
   
       31 . The grid according to  claim 9  wherein the polymer filling the cells is the same as the polymer of the substrate.  
   
   
       32 . The grid according to  claim 1  wherein the ratio of the grid thickness to the distance between partitions is a ratio of greater than 10.  
   
   
       33 . The grid according to  claim 1  wherein the grid has a thickness of greater than about 1.6 mm and less than about 3 mm.  
   
   
       34 . The grid according to  claim 1  wherein the grid has thickness of greater than about 0.4 mm and less than about 1 mm.  
   
   
       35 . The grid according to clam  1  wherein the cells have a polyhedral shape.  
   
   
       36 . The grid according to  claim 1  wherein the cells have a quasi-periodic pattern.  
   
   
       37 . The grid according to  claim 1  wherein the cells have a pattern in which the pitch or the period varies continuously.  
   
   
       38 . A radiology imaging apparatus comprising: 
 a source for emitting radiation;    an image receiver for the emitted radiation; and    an antiscattering grid disposed between the source and the image receiver;    the grid comprising a substantially planar substrate of a polymer material having a plurality of metallized polymer partitions that define a plurality of cells distributed over the substrate;    the partitions allowing passage of the emitted radiation from a source lying in line with the grid;    the partitions disposed for absorbing the radiation not coming directly from the source; and    the partitions are oriented to form a focused grid.    
   
   
       39 . The grid according to  claim 38  wherein the ratio of the grid thickness to the distance between partitions is a ratio of greater than 8.  
   
   
       40 . An antiscattering grid for emitted radiation comprising: 
 a substantially planar substrate of a polymer material having a plurality of metallized polymer partitions that define a plurality of cells distributed over the substrate;    the partitions allowing passage of the emitted radiation from a source lying in line with the grid;    the partitions disposed for absorbing the radiation not coming directly from the source; and    the partitions are oriented to form a focused grid.    
   
   
       41 . The grid according to  claim 40  wherein the ratio of the grid thickness to the distance between partitions is a ratio of greater than 8.