| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an encoder capable of multidimensional measurement of changes in relative position between objects at an identical measuring point. <P>SOLUTION: An encoder 1 comprises: a separation section 3 that separates illumination light L0 in two directions crossing each other on a light separation plane 30; an illumination system 2 that causes the illumination light L0 to scan in a direction crossing both of the two directions on the light separation plane 30; a scale 5 that relatively moves with respect to the separation section 3; an optical system 4 that guides first beams of light L11 and L12 separated in a first direction in the two directions and the second beams of light L21 and L22 separated in a second direction to the scale 5 and causes spots S11 and S12 of the first beams of light L11 and L12 and spots S21 and S22 of the second beams of light L21 and L22 to overlap with each other on the scale 5; and a detection section 6 that detects the first beams of light L11 and L12 and the second beams of light L21 and L22 coming through the scale 5. <P>COPYRIGHT: (C)2012,JPO&INPIT |
