Scintillator having integrated collimator and method of manufacturing same

Abstract

The present invention is directed to an integrated scintillator and collimator array for a CT detector. The integrated scintillator and collimator are fabricated from a manufacturing process or technique whereupon an array of scintillator material is positioned on a tooling base such that a collimator mold housing having a collimator mold therein may be positioned on the block of scintillator material. The block and mold housing are then aligned allowing a collimator mixture to be disposed into the mold. The collimator mixture is then allowed to cure to form an integrated scintillator and collimator.

1 . A detector comprising: 
 a scintillator having a 2D array of scintillation elements arranged to convert received x-rays to light; and    a collimator having either a 1D or a 2D array of collimator elements molded to an x-rays reception surface of the scintillator to collimate x-rays toward individual scintillation elements.    
   
   
       2 . The detector of  claim 1  wherein each of the collimator elements is fabricated from a tungsten/epoxy combination.  
   
   
       3 . The detector of  claim 1  wherein the collimator elements are arranged along two dimensions.  
   
   
       4 . The detector of  claim 1  incorporated into a computed tomography (CT) imaging system.  
   
   
       5 . The detector of  claim 4  wherein the CT imaging system includes one of a medical scanner or a parcel inspection apparatus.  
   
   
       6 . The detector of  claim 1  wherein the collimator is integrally bonded to the x-rays reception surface of the scintillator.  
   
   
       7 . A computed tomography (CT) imaging apparatus comprising: 
 a rotatable gantry having an opening to receive a scan subject;    a high frequency electromagnetic energy projection source configured to project a high frequency electromagnetic energy beam toward the scan subject;    a detector assembly configured to detect high frequency electromagnetic energy passing through the subject, the detector assembly having: 
 an array of scintillator cells;  
 a series of collimator plates cast directly onto the array of scintillator cells; and  
 an array of photodiodes configured to detect light emissions from the array of scintillator cells;  
   a data acquisition system (DAS) connected to the detector and configured to receive outputs from the array of photodiodes; and    an image reconstructor connected to the DAS and configured to reconstruct an image of the scan subject from the outputs received by the DAS.    
   
   
       8 . The CT imaging apparatus of  claim 7  wherein the array of scintillator cells comprises a plurality of scintillator cells divided by reflector lines therebetween.  
   
   
       9 . The CT imaging apparatus of  claim 8  wherein the series of collimator plates are substantially aligned over the reflector lines.  
   
   
       10 . The CT imaging apparatus of  claim 7  wherein the detector assembly further includes an integral bond between the array of scintillator cells and the series of collimator plates.  
   
   
       11 . The CT imaging apparatus of  claim 10  wherein the integral bond is free of an additional adhesive substance.  
   
   
       12 . The CT imaging apparatus of  claim 10  wherein the integral bond is substantially free of air gaps.  
   
   
       13 . The CT imaging apparatus of  claim 7  wherein the series of collimator plates are aligned to extend vertically from the array of scintillator cells and are rigidly held in place by a surface-to-surface molding.  
   
   
       14 . A method for manufacturing a CT detector comprising: 
 fitting a collimator mold onto a block of scintillation material;    dispensing a collimator mixture into the collimator mold, onto at least a portion of the block of scintillation material; and    forming an integral bond between the collimator mixture and the portion of the block of scintillation material, wherein the bond is free of glue.    
   
   
       15 . The method of  claim 14  wherein fitting the collimator mold onto the block of scintillation material includes aligning a number of openings of the collimator mold with a number of reflector lines formed in the block of scintillation material.  
   
   
       16 . The method of  claim 15  further comprising forming a vacuum in the number of openings of the collimator mold before dispensing the collimator mixture.  
   
   
       17 . The method of  claim 14  wherein the collimator mixture is a tungsten-epoxy powder.  
   
   
       18 . The method of  claim 14  wherein forming the integral bond includes allowing the collimator mixture to cure directly to the portion of the block of scintillation material.  
   
   
       19 . The method of  claim 18  further comprising removing the collimator mold from the block of scintillation material only after the collimator mixture has cured.  
   
   
       20 . The method of  claim 14  further comprising milling the block of scintillation material to improve the integral bond with the collimator mixture.  
   
   
       21 . The method of  claim 14  wherein forming the integral bond includes molding the collimator material directly to the portion of the scintillation material such that no air gaps exist between the collimator material and the scintillation material.