Method of manufacturing rotary scale, rotary scale, rotary encoder, driving apparatus, image pickup apparatus and robot apparatus

Abstract

A method of manufacturing a rotary scale to be fixed to a rotating shaft of a rotating member includes a first step of forming, on a scale substrate, a scale pattern and a mark indicating an outer shape of the rotating shaft positioned such that a center axis of the rotating shaft coincides with a center axis of the scale pattern, a second step of cutting a first area of the scale substrate including the mark and having a first width, and a third step of cutting a second area including the mark that remains after the cutting of the first area, having a length in a circumferential direction of the scale substrate shorter than that in the first area and having a second width narrower than the first width.

What is claimed is: 
     
         1 . A rotary scale to be fixed to a rotating shaft of a rotating member, the rotary scale comprising:
 a scale pattern; and   a protrusion formed by cutting a first area of the rotary scale that includes a mark indicating an outer shape of the rotating shaft positioned such that a center axis of the rotating shaft coincides with a center axis of the scale pattern and that has a first width and then cutting a second area, the second area including the mark that remains after the cutting of the first area, having a length in a circumferential direction of the rotary scale shorter than that in the first area and having a second width narrower than the first width.   
     
     
         2 . The rotary scale according to  claim 1 , wherein the protrusion is provided at least three locations in the circumferential direction. 
     
     
         3 . The rotary scale according to  claim 1 , wherein the protrusion is provided more inside than the scale pattern. 
     
     
         4 . The rotary scale according to  claim 1 , wherein the protrusion is provided more outside than the scale pattern. 
     
     
         5 . The rotary scale according to  claim 1 , wherein the protrusion has a taper shape formed by cutting the first area. 
     
     
         6 . A rotary encoder comprising:
 a rotary scale to be fixed to a rotating shaft of a rotating member; and   a detector configured to detect light reflected by the rotary scale,   wherein the rotary scale includes:   a scale pattern; and   a protrusion formed by cutting a first area of the rotary scale that includes a mark indicating an outer shape of the rotating shaft positioned such that a center axis of the rotating shaft coincides with a center axis of the scale pattern and that has a first width and then cutting a second area, the second area including the mark that remains after the cutting of the first area, having a length in a circumferential direction of the rotary scale shorter than that in the first area and having a second width narrower than the first width.   
     
     
         7 . A driving apparatus comprising:
 a driver configured to rotate a rotating member; and   a rotary encoder provided with a rotary scale to be fixed to a rotating shaft of the rotating member and a detector configured to detect light reflected by the rotary scale,   wherein the rotary scale includes:   a scale pattern; and   a protrusion formed by cutting a first area of the rotary scale that includes a mark indicating an outer shape of the rotating shaft positioned such that a center axis of the rotating shaft coincides with a center axis of the scale pattern and that has a first width and then cutting a second area, the second area including the mark that remains after the cutting of the first area, having a length in a circumferential direction of the rotary scale shorter than that in the first area and having a second width narrower than the first width.