Abstract:
An example system for inspecting fiber optic cables includes: a fixture including a body configured to hold a plurality of fiber optic cables, the fixture including a front portion defining a plurality of apertures positioned adjacent to ends of the fiber optic cables; and an adapter including two or more pin members extending therefrom, the two or more pin members being configured to be positioned in two or more of the plurality of apertures in the fixture to hold the fixture relative to the adapter.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
       [0001]    This application claims priority to U.S. Patent Application Ser. No. 61/881,291 filed on Sep. 23, 2013 and U.S. Patent Application Ser. No. 61/881,417 filed on Sep. 23, 2013, the disclosures of which are incorporated herein by reference in their entireties. 
     
    
     BACKGROUND 
       [0002]    Fiber optic connectors are used to terminate the ends of fiber optic cables. There are many different fiber optic connector types. Example types of fiber optic connectors include FC-type, SC-type, ST-type and D4-type. 
         [0003]    A typical connector includes a ferrule located inside the connector. The ferrule is a relatively long, thin cylinder made of a material such as ceramic. Other materials such as metal or plastic can also be used to make the ferrule. The ferrule defines a central opening sized to receive a fiber of a given cladding diameter. An epoxy is typically placed into the opening prior to inserting the fiber to hold the fiber in place. The ferrule functions to align and center the fiber, as well as to protect it from damage. 
         [0004]    It is desirable to minimize the loss of signals passing through the fiber. Parameters for evaluating the performance of a connector include insertion loss and return loss. Insertion loss is the measurement of the amount of power that is transferred through a coupling from an input fiber to an output fiber. Return loss is the measurement of the amount of power that is reflected back into the input fiber. To enhance signal quality and therefore optimize insertion/return loss, it is desirable to inspect each connector during manufacture. 
       SUMMARY 
       [0005]    In one aspect, an example system for inspecting fiber optic cables includes: a fixture including a body configured to hold a plurality of fiber optic cables, the fixture including a front portion defining a plurality of apertures positioned adjacent to ends of the fiber optic cables; and an adapter including two or more pin members extending therefrom, the two or more pin members being configured to be positioned in two or more of the plurality of apertures in the fixture to hold the fixture relative to the adapter. 
     
    
     
       DESCRIPTION OF THE FIGURES 
         [0006]      FIG. 1  is a top perspective view of an example system for inspecting fiber optic cables. 
           [0007]      FIG. 2  is an enlarged view of a portion of an example adapter and fixture of the system of  FIG. 1 . 
           [0008]      FIG. 3  is a bottom perspective view of the system of  FIG. 1 . 
           [0009]      FIG. 4  is a top view of the system of  FIG. 1 . 
           [0010]      FIG. 5  is a bottom view of the system of  FIG. 1 . 
           [0011]      FIG. 6  is a front view of the system of  FIG. 1 . 
           [0012]      FIG. 7  is a perspective view of the system of  FIG. 1  positioned to engage an inspection device. 
           [0013]      FIG. 8  is a perspective view of an example inspection plate and adapter. 
           [0014]      FIG. 9  is a perspective view of the inspection plate and adapter of  FIG. 8 , along with a fixture including a plurality of fiber optic cables. 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    The present disclosure relates to systems and methods for inspecting fiber optic cables. 
         [0016]    Referring now to  FIGS. 1-6 , an example system  100  for inspecting fiber optic connectors is provided. 
         [0017]    In this example, the system includes a fixture  110  and an adapter  130 . 
         [0018]    The fixture  110  holds a plurality of fiber optic cables, in this embodiment a flexible circuit  112 . The flexible circuit  112  is terminated using a hub  162  and a ferrule  118  holding a fiber therein. The flexible circuit  112  is loaded into the fixture  110  by pivoting a clamp arm  150  about a hinge  154  from a closed position (shown in  FIG. 1 ) into an open position. The clamp arm  150  is locked in the closed position by a fastening member  152 . By pulling the fastening member  152 , the fastening member  152  is released from the fixture  110 , allowing the clamp arm  150  to pivot upwardly about the hinge  154  away from the fixture  110  and the flexible circuit  112  to be positioned in the fixture  110 . 
         [0019]    Once in position in the fixture  110 , the flexible circuit  112  is pulled so that the hub  162  of each of the fibers is seated in a holder  160 . The holders  160  position in the ferrules  118  and maintain the ferrules  118  in place during inspection. Once in place, the clamp arm  150  is pivoted back towards the fixture  110  until the fastening member  152  engage the fixture  110  to hold the flex circuit  112  in place. 
         [0020]    The fixture  110  also includes a front portion  114  defining a plurality of apertures  116  sized to receive a portion of the adapter  130 , as described further below. 
         [0021]    Examples of fixtures similar to the fixture  110  described herein are provided in U.S. Patent Application Ser. No. 61/707,480 filed on Sep. 28, 2012, the entirety of which is hereby incorporated by reference. Other configurations are possible. 
         [0022]    The adapter  130  includes a base portion  132  and an upper portion  134 . The base portion  132  is coupled to the upper portion  134  by an adjustment mechanism  136 . By turning the adjustment mechanism  136 , the base portion  132  is moved relative to the upper portion  134  in the directions  610  (see  FIG. 6 ). In this manner, the position of the fibers in the ferrules  118  in the fixture  110  are raised or lowered when the fixture  110  is coupled to the adapter  130  (see  FIGS. 7-9 ). 
         [0023]    The adapter  130  also includes openings  612 ,  614  in the adapter  130  to allow the ferrules  118  positioned at the adapter  130  to be accessible through the adapter  130 . See  FIG. 6 . In this example, the opening  612  allows the ferrule  118  under inspection to be accessed. The opening  614  is oversized to allow an adjacent ferrule  118  to be accepted into the adapter  130 . The opening  614  is oversized because the spacing between each pair of ferrules  118  of the flexible circuit  112  is different from the spacing between each ferrule  118  making up a pair. The oversized opening  614  accommodates this difference in spacing. 
         [0024]    Referring now to  FIG. 7 , an example inspection head  710  is shown. The inspection head  710  can be part of an inspection device used to inspect fiber optic cables, such as an interferometer. The adapter  130  is coupled to the inspection head  710 . 
         [0025]    To couple the adapter  130  to the fixture  110 , the fixture  110  is moved in the direction  712  until pin members  138  of the adapter  130  are received in the desired apertures  116  on the fixture  110 . Specifically, the apertures  116  that are positioned adjacent to the ferrule  118  to be inspected are selected so that the ferrule  118  is positioned at the inspection head  710 . The pin members  138  function to guide the fixture  110  to the appropriate position relative to the inspection device for inspection. 
         [0026]    Once the fixture  110  is coupled to the adapter  130 , the adapter  130  holds the fixture  110  in place during inspection. If the fiber in the ferrule  118  under inspection needs to be lowered or raised, the adjustment mechanism  136  is turned clockwise or counterclockwise to lower or raise the fixture  110 . 
         [0027]    When inspection is complete, the fixture  110  is moved in a direction opposite to that of the direction  712  to remove the pin members  138  from the corresponding apertures  116 . At that point, the fixture  110  can be moved in the directions  714 ,  716  and reengaged with the adapter  130  if further inspection of a fiber in another ferrule  118  is desired. 
         [0028]    Referring now to  FIGS. 8-9 , an inspection plate  810  is shown. The inspection plate  810  is configured to be mounted to an inspection device, such as a microscope used to inspect fibers. 
         [0029]    The adapter  130  is mounted to the inspection plate  810  by attachment mechanisms  812  that are received in grooves defined by the adapter  130 . When in place, the attachment mechanism  812  are tightened (e.g., by rotation) to affix the adapter  130  to the inspection plate  810 . 
         [0030]    For inspection, the fixture  110  is brought in a direction  910  towards the adapter  130  until the pin members  138  are received in the apertures  116  adjacent to the ferrule  118  to be inspected. In this position, the fiber in the ferrule  118  can be inspected. 
         [0031]    Although various embodiments are described herein, those of ordinary skill in the art will understand that many modifications may be made thereto within the scope of the present disclosure. Accordingly, it is not intended that the scope of the disclosure in any way be limited by the examples provided.