| 摘要 |
PROBLEM TO BE SOLVED: To provide a scale which easily performs pattern formation of the scale and can improve detection accuracy of an encoder by removing harmonic components.SOLUTION: In a main scale 10, rectangular slits 12 are formed in an X direction at an interval of a pitch λ. In an index scale 20, slit columns 22 extending in a Y direction as a whole are formed. In the slit columns 22, respective center lines are arranged in an X direction with an interval of λ. Each of the slit columns 22 has a slit pattern 31 (32) configured by connecting in the Y direction four division slits 41 to 44 (51 to 54) having the same length in the Y direction. The division slits 41 to 44 (51 to 54) have width obtained by adding either three-order harmonic wave adjustment width +λ/6 or -λ/6 and either five-order harmonic wave adjustment width +λ/10 or -λ/10 to a prescribed average width A. |
