| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve the problem wherein, since a probe optical path is separated spatially from a reference optical path, when a temperature distribution, a refractive index distribution or a mechanical vibration is generated by fluctuation of the air or the like, an optical path difference is fluctuated between both optical paths to generate a measurement error, in a displacement measuring device using optical interference. <P>SOLUTION: The optical axis of probe light and the optical axis of reference light are brought close up to a distance uninfluenced by a disturbance, and an object is irradiated with the probe light and a reference plane is irradiated with the reference light respectively, and each reflected light is allowed to interfere with each other, and displacement of the object is determined from generated interference light. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
