| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high-accuracy low-cost encoder capable of accurately determining an address, and facilitate identification of neighborhood of address switching location. <P>SOLUTION: An absolute encoder comprises a scale part (20) that at least includes: a main track which includes first scales formed at equal intervals at a first wavelength (λ) and is configured to regulate a first address section with nλ (n represents an extension number, and λ represents the first wavelength); a first address track which includes second scales formed at equal intervals so as for an address section identical to the first address to have (n+1)λa (λa represents a second wavelength); and a second address track which includes third scales formed in such a manner that the address section identical to the first address section has n(λa+(n<SP POS="POST">2</SP>-1)λ)+λa. And, the absolute encoder comprises processing means (30, 40, 50, 60, 70 and 80) for: detecting a phase difference from the scales; determining an address on the basis of the multiple detected phase differences; and calculating a location or angle of a measured object. <P>COPYRIGHT: (C)2013,JPO&INPIT |
