| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a technology which is advantageous for higher resolution of a two-dimensional absolute encoder. <P>SOLUTION: A two-dimensional absolute encoder includes: a scale in which marks are two-dimensionally arranged at predetermined pitches in a first direction and a second direction orthogonal to each other; a detector which detects the first number of marks arranged in the first direction, and detects the second number of marks arranged in the second direction; and a processing unit which determines absolute positions of the scale in the first and second directions, respectively, on the basis of outputs of the detector. Each of the marks has quantized information on a first code for showing a position in the first direction and quantized information on a second code for showing a position in the second direction. The processing unit generates a first code string from detection results of the first number of marks, calculates the absolute position of the scale in the first direction from the first code string, generates a second code string from detection results of the second number of marks, and calculates the absolute position of the scale in the second direction from the second code string. <P>COPYRIGHT: (C)2013,JPO&INPIT |
