| 摘要 |
<p>A known method of measuring angular displacement of a shaft (11) using an optical grating mounted for rotation with the shaft is applied at two or more angularly spaced locations (16, 17 and 18) and the resulting measurements are processed to produce a measurement of relative displacement of the shaft in a direction transverse to the shaft. Two locations are needed to measure displacement in a given direction. Three or more locations are necessary to provide full information about the displacement of the shaft.</p> |
