| 摘要 |
PROBLEM TO BE SOLVED: To provide a position detection encoder capable of detecting a position with high accuracy regardless of a relative movement amount (relative movement speed) between a scale and a sensor.SOLUTION: A position detection encoder comprises: a scale 10 having first and second period patterns 11, 12 that have different periods; a sensor 20 switchable between a first detection condition where the first period pattern is read to output a first period signal and a second detection condition where the second period pattern is read to output a second period signal having a period that is longer than that of the first period signal; and a processing unit 30 for calculating a position in a direction of relative movement between the scale and the sensor using the first and second period signals. The processing unit receives the second period signal, the first period signal, and the second period signal in this order at different clock times, calculates phases of the second, first, and second period signals at specific clock times, and, by using the calculated phases, calculates a position at a specific clock time. |
