| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an encoder capable of obtaining a change in pulse width close to an actual speed change even when the speed of a movable member changes rapidly.SOLUTION: The encoder has: a sensor 20, capable of moving relatively to a scale 10, for detecting a cyclic pattern 11 of the scale and outputting a cyclic signal; phase detection means 32 for detecting the phase of the cyclic signal every first prescribed time; pulse count calculation means 33 for calculating the number of generated pulses corresponding to a difference between the first and second phases detected as the phase; pulse count smoothing means 34 for smoothing out the number of generated pulses by a second prescribed time longer than the first prescribed time and calculating the number of outputted pulses every first prescribed time; and pulse generation means 35 for generating a pulse signal corresponding to the number of outputted pulses within the first prescribed time. The pulse count smoothing means calculates the number of outputted pulses pexpressed by p=CEIL[(q+r)/c],q=q+r-p.</p> |
