摘要 |
An encoder includes a scale, a detector array that includes a plurality of detectors, and a signal processor configured to process and convert into positional information, an output signal from the detector array. The signal processor includes a first phase acquirer configured to acquire a first phase of a first modulation period from an output signal of the detector array. The encoder further includes a weighting unit configured to weight an output signal from each of a plurality of detectors using a weight in accordance with a position of the detector array. The weight is set so that in a predetermined range that contains a spatial frequency corresponding to the second modulation period in a spatial frequency response of the first phase acquirer, a value weighted by the weighting unit is equal to or smaller than a non-weighted value. |