| 摘要 |
<p>A magnetic scale includes a scale member having a plurality of grooves. The scale member defines a passive magnetic scale track. The plurality of grooves include grooves of at least a first groove type and a second groove type, the magnetic properties of the scale member in the locality of grooves of the first groove type being different than the magnetic properties of the scale member in the locality of grooves of the second groove type. The scale member is arranged to carry or encode absolute position information in the form of at least one codeword comprising a sequence of data bits, wherein each of the data bits is provided by a groove of the scale member, the data bit taking a first value if the groove is of the first groove type and a second value if the groove is of the second groove type.</p> |
