| 摘要 |
PROBLEM TO BE SOLVED: To provide an encoder including a first sensor and a second sensor for detecting a rotation angle of a rotator, in which abnormality of the first sensor and the second sensor can be detected with a simple configuration.SOLUTION: An encoder 1 includes: a first sensor 9 and a second sensor 10 for detecting a rotation angle of a rotator; and a rotation angle detection unit 11 which calculates the rotation angle of the rotator on the basis of a first output signal being an output signal from the first sensor 9 and a second output signal being an output signal of the second sensor 10. The level of the first output signal is periodically varied in accordance with the rotation angle of the rotator, and the level of the second output signal is periodically varied in accordance with the rotation angle of the rotator and is varied with a period different from that of the first output signal. The rotation angle detection unit 11 detects abnormality of the first sensor 9 and the second sensor 10 on the basis of states of variation in the level of the first output signal and the second output signal. |
