| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an autonomous calibration method of an angle detector, which is capable of accurately calculating a scale error in each angular position of one rotation by employing a sequential two-points method. <P>SOLUTION: In the autonomous calibration method of an angle detector, a first scale reading head 11 and a second scale reading head 12 are arranged at an angular interval α which does not equally divide one rotation by an integer but equally divides a plurality of rotations N by an integer M, and readings of the first and second scale reading heads 11 and 12 during N rotations of divided circles are taken into a data reader 13 at preliminarily determined data sampling intervals. The data reader 13 generates data based on a sequential two-points method, which is obtained at the data sampling intervals and relates to an angle scale error of the divided circles 4 and 5, from the difference between readings of the first and second scale reading heads 11 and 12, and the fact that an average of data during the plurality of rotations N is zero is utilized to obtain a scale error (calibration value) of the divided circles 4 and 5 by combining data. <P>COPYRIGHT: (C)2013,JPO&INPIT |
