| 摘要 |
PROBLEM TO BE SOLVED: To provide an apparatus and a method for measuring a distance which can shorten the time required for measuring the distance. SOLUTION: The apparatus for measuring the distance has a light source 10, a splitter 11, an observation plane 16 and a reference light group forming means 17. The light emitted from the light source 10 is split into measuring light and first reference light by the splitter 11. The first reference light is split into a plurality of second reference lights which are different in the optical path length from each other, and each second reference light arrives at a position different from others on the observation plane 16. Accordingly, the position on the observation plane 16 and the optical path length of the second reference light are made to correspond to each other. Additionally, the measuring light is reflected by a measuring object 13 and then arrives at the observation plane 16. An interference fringe on the observation plane 16 is brought about, when the optical path length of the measuring light and that of the second reference light are equal to each other; and since the position of the interference fringe on the observation plane 16 corresponds to the optical path length of the second reference light, the distance to the measuring object 13 can be measured instantaneously from the position of the interference fringe. COPYRIGHT: (C)2010,JPO&INPIT |
