Patent Publication Number: US-2013236677-A1

Title: Detector and method of panel bonding using removable adhesive film

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a method of manufacturing a detector, in particular to a method of manufacturing a flat panel detector of a medical imaging diagnostic device. 
     The flat panel detector is an important component of an X-ray detector and is relatively expensive. During assembling, bad pixels usually appear in the flat panel detector due to Electrostatic Discharge (ESD), and the performance of the flat panel detector also degrades during the use thereof. Such flat panel detectors can be repaired with a laser. Replacement and repair of the flat panel detector, namely, using a reusable flat panel detector, can save on the production cost of the X-ray detector. There are two ways available at present for bonding the flat panel detector. One method of making the flat panel detector reusable is adhering the four sides of the flat panel detector to the panel detector support using the Room Temperature Vulcanized Silicone Rubber (which is referred to as “the RTV adhering method” for short). The problem with this method is that the RTV at the edge of the flat panel detector and the foam under the flat panel detector make the edge and the middle part of the flat panel detector have different a strength and stiffness, resulting in non-uniform weight distribution on the surface of the flat panel detector, thus making the flat panel detector very fragile. Another method is bonding the entire surface of the flat panel detector on the panel detector support (which is referred to as the “entire surface bonding method”), but the flat panel detector bonded in this way cannot be reused once it is damaged. 
     U.S. Pat. Nos. 7,396,159, 7,244,945, and 6,847,041 each disclose some ways of bonding the flat panel detector on the panel detector support. 
     BRIEF DESCRIPTION OF THE INVENTION 
     With respect to the above problem, in one aspect, a method of manufacturing a detector is provided. The method includes bonding the flat panel detector and the panel detector support using a removable double-faced adhesive film. 
     In one embodiment, the removable double-faced adhesive film is adhered between the planes of the flat panel detector and the panel detector support and is removed immediately after the adhering, or is removed after a period of time. 
     The adhesive film is removed by pulling forcibly the end thereof, and the pulling may be performing using tools or control methods. 
     In one embodiment, the removable double-faced adhesive film is adhered to the four sides of the flat panel detector. 
     In one embodiment, the removable double-faced adhesive film is adhered to the entire surface of the flat panel detector. 
     In one embodiment, the removable double-faced adhesive film is arranged to be diverging from the center of the flat panel detector to its surroundings, and ends of the adhesive films are left at outside of the surface of the flat panel detector, so that the adhesive films are removed by pulling the ends thereof. 
     In one embodiment, the removable double-faced adhesive film is in a strip spiral arrangement. 
     In one embodiment, the removable double-faced adhesive film is arranged in such a way that the surface of the flat panel detector is divided into four triangular areas by two crossing diagonals, the strip adhesive films connecting end to end in succession in each area. 
     In one embodiment, the removable double-faced adhesive film is an optical adhesive film with a thickness of 100-200 microns. 
     In one embodiment, a layer of black glass priming paint is added at the backside of the flat panel detector. 
     The embodiments described herein utilize a removable double-faced adhesive film to bond the flat panel detector, so that the flat panel detector can be easily removed after being bonded. The assembly method described herein has both the advantages of high firmness and reliability as in the original entire surface bonding method, and overcomes the defect that the flat panel detector cannot be repaired or reused. By means of the assembling method described herein, the flat panel detector can be easily removed or repaired, thus greatly reducing the manufacturing cost. In addition, by means of the assembling method described herein, the weight distribution on the surface of the flat panel detector is uniform, and the panel detector support can more effectively support the flat panel detector, thereby improving the reliability of the flat panel detector. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram illustrating an RTV adhering method for a flat panel detector. 
         FIGS. 2A and 2B  are schematic diagrams illustrating an exemplary method for manufacturing a detector; 
         FIGS. 3A and 3B  are schematic diagrams of two arrangements of adhesive films that may be used with the method illustrated in  FIG. 1 ; 
         FIG. 4  is a schematic diagram illustrating an exemplary method of adding a layer of black glass priming paint to reduce the scattered rays of the adhesive film that may be used with the method illustrated in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Systems and methods will be described in further detail below through specific embodiments, but are not limited to the specific embodiments described herein. 
     The specific embodiments are described in detail below in conjunction with the drawings, but these embodiments are not intended to be limiting. The same components in different drawings are denoted by the same reference signs. 
       FIG. 1  is a schematic diagram illustrating an RTV adhering method for a flat panel detector. 
       FIG. 1  shows the principle of the original RTV adhering method, wherein the four sides of the flat panel detector  1  are adhered to the panel detector support  2  using RTV  5 . Such a method results in a non-uniform distribution of weight on the surface of the flat panel detector  1 , so the flat panel detector  1  is very fragile. 
       FIGS. 2A and 2B  are schematic diagrams illustrating an exemplary method for manufacturing a detector, wherein the flat panel detector  1  is adhered to the panel detector support  2  through a new removable double-faced adhesive film  3 .  FIG. 2A  shows the adhesive film  3  arranged between the flat panel detector and the panel detector support  2 . The removable double-faced adhesive film  3 , such as an optical adhesive film of 100-200 microns, is adhered between two rolling depression planes of the flat panel detector  1  and the panel detector support  2 , and is removed immediately after being adhered or is removed after a period of time. The arrangement of the adhesive film  3  is designed in such a way that it is removed by pulling the end thereof forcibly or by pulling with tools or control methods. By means of such a method, the flat panel detector  1  can be easily removed. Further, the surface of the flat panel detector  1  has a uniform weight distribution, so it will not be easily damaged. 
     A plurality of possible arrangements of adhesive films may be used. For example,  FIG. 2B  shows one kind of adhesive film arrangement of adhering at the four sides of the flat panel detector  1 . 
       FIGS. 3A and 3B  show two arrangements of strips of adhesive film  3  adhered to an entire surface of the flat panel detector  1 . 
     In  FIG. 3A , the strip of adhesive film  3  is in a spiral arrangement, which diverges from the center of the flat panel detector, with the end  21  of the strip of adhesive film  3  extending beyond the surface of the flat panel detector. After adhering the flat panel detector  1  to the panel detector support  2  through the adhesive film  3 , the strip of adhesive film  3  is pulled. That is, the end  21  of the adhesive film  3  is pulled out forcibly. When arranging the adhesive film  3 , the adhesive film  3  may be adhered to the panel detector support  2 , and then spiral lines are cut on the surface of the adhesive film  3 , or a sheet of the adhesive film  3  is pre-cut in this spiral manner. 
     In  FIG. 3B , the surface of the flat panel detector  1  is divided into four triangular areas by two crossing diagonals, with strips of adhesive film  3  connecting end to end in succession in each area, and the ends  21 ,  22 ,  23  and  24  of the strips of adhesive film  3  extending beyond the surface of the flat panel detector  1 . After adhering the flat panel detector  1  to the panel detector support  2  through the adhesive film  3 , the strips in the four areas are each pulled. Specifically, the ends  21 ,  22 ,  23  and  24  of the strips of adhesive film  3  left outside of each area are pulled out forcibly. When arranging the adhesive film  3 , the adhesive film  3  may be adhered to the panel detector support  2 , then two diagonals are cut on the adhesive film  3 , and then vertical and horizontal lines are further cut in the four triangular areas formed by two crossing diagonals, while leaving an end  21 ,  22 ,  23 ,  24  of each strip of adhesive film  3  outside of each area. 
     Both of the two entire surface adhering methods shown in  FIGS. 3A and 3B  involve pulling the adhesive film strips from the edges. Thus the arrangement of the adhesive film strips must be starting from the center and diverging to the edges to cover the entire surface area of the flat panel detector  1 . 
     If the adhesive film arrangement is in a diverging shape and non-uniform, since the adhesive film  3  is in the light-transmissive area behind the flat panel detector  2 , the air bubbles or edge imprints generated during the adhering process may appear in the images, and may lead the doctors to a misdiagnosis. Even if a gain calibration method is used during assembling of the flat panel detector  1 , air bubbles or adhesive film edge imprints may still occur after a long time.  FIG. 4  is a schematic diagram illustrating an assembling method of adding a layer of black glass priming paint  4  at a backside of the flat panel detector  1  for blocking the adhesive film air bubbles or the edge scattered rays. Specifically, the priming paint  4  is located between the flat panel detector and the adhesive film  3 . Accordingly, the layers are flat panel detector  1 , panel detector support  2 , removable adhesive film  3 , and black glass priming paint  4 . The layer of black glass priming paint  4  can also help to improve the EDS reliability of the flat panel detector. 
     The manufacturing method of a detector as described herein can also be applied to manufacturing of other flat panel detectors (e.g. LCD) in addition to the manufacturing of the flat panel detector used for medical imaging diagnostic devices (e.g. X-ray imaging system, CT device). 
     The embodiments described above are only for illustration, and in no way limit the scope of the present invention. It shall be noted that those ordinarily skilled in the art will be able to make many improvements, modifications and variations to the present invention, and these improvements, modifications and variations, which are not departing from the spirit of the present invention, shall be considered as falling within the scope of the present application.