| 摘要 |
<p>1. A method of measuring selected spacing characteristics in a pattern (20) of contrasted plane fringes (24), characterized in that a light beam (18a) is focused on a point of said fringe pattern such that a part of said beam, modulated by said point after having gone through said pattern (20), is picked up by a photocell (22) ; said pattern (20) is made to move in gradual steps in relation to the light beam (18a) such as to scan a specific area of said pattern (20) in one direction of measurement ; the luminous intensity picked up by the photocell (22) is measured at each step, referred to the coordinates of the point being measured, so as to constitute a data pair, and the data pair thus obtained is digitally processed as required to obtain the selected spacing characteristics at the end of the measurement run.</p> |
