| 摘要 |
The invention relates to a scale pattern which is placed in the close proximity of a measuring point whose position is to be determined in at least one dimension with the aid of a narrow measuring beam which moves in one plane and sweeps over the scale pattern as it moves. The scale pattern is such that when an indicating arrangement which indicates impingement of the measuring beam on the scale pattern gives rise to different signal patterns from a beam detector (25) for different heights at which the measuring beam sweeps over the scale pattern. The scale pattern has reflective and non-reflective pattern parts. Each scale pattern includes part-patterns (63, 64; 84, 85; 90, 91; 102, 105) which are operative in providing time or position scale-calibration for the signal pattern obtained from the beam detector (25) as the measuring beam sweeps over the scale pattern.
|
