Patent ID: 11906783
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 4:
5. A connection apparatus, comprising:
a connector that connects an end of a multi-core fiber and a device serving as a connection destination;
a camera that observes the multi-core fiber from a lateral side so as to include the end;
an interval measuring instrument that measures, from an image observed by the camera, an interval χ′ between a longitudinal contour among contours of the multi-core fiber, and a line drawn on a side surface of the multi-core fiber, the line having a predetermined length and extending longitudinally from the end of the multi-core fiber; and
a calculator that calculates a rotation amount x of the multi-core fiber using Formula C1:, [
  
   
    Math
    .
       
    C
   
   ⁢
   1
  
  ]
 

 
  
   
    
     χ
     =
     
      
       
        cos
        
         -
         1
        
       
       (
       
        
         
          a
          1
         
         -
         
          χ
          ′
         
        
        
         a
         1
        
       
       )
      
      -
      ϕ
     
    
   
   
    
     (
     C1
     )
    
   
  
 

where a1 is a radius of the multi-core fiber, and
an angle ϕ is an angle formed between a straight line passing through a marker of the multi-core fiber and a center of the multi-core fiber, and a straight line passing through the line and the center of the multi-core fiber, on a cross section of the multi-core fiber at the end.