POSITION DETECTION DEVICE, LENS DEVICE, IMAGING SYSTEM, MACHINING DEVICE, POSITION DETECTION METHOD, PROGRAM AND STORAGE MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide a position detection device that can highly accurately detect irregularity such as a foreign matter adhesion on a scale or defect of a scale pattern, or the like, and is excellent in reliability.SOLUTION: A position detection device detecting a position of a measurement object is provided which comprises: a scale that has a pattern cyclically formed; detection means that is configured to be relatively movable with respect to the scale; and signal processing means that acquires position information on the measurement object on the basis of a first signal from the detection means and performs irregularity determination on the basis of a second output signal from the detection means. A second spatial frequency at which a spatial frequency response for the second output signal peaks is different from a first spatial frequency at which a spatial frequency response for the first output signal peaks, and is not zero.SELECTED DRAWING: Figure 5