| 摘要 |
PROBLEM TO BE SOLVED: To provide minute displacement measuring equipment wherein precise optical adjustment, light phase adjustment, highly precise adjustment of the initial position of an object to be measured, complicated synchronous measurement, etc., are unnecessary, operation is simple, and miniaturization and cost reduction are enabled. SOLUTION: A light entering an optical fiber 30 from a laser oscillator 40 propagates in a rectilinear optical waveguide 12, and a part of the light is reflected on account of difference of refractive index. The light entering the waveguide 12 is cast on an object 80 to be measured from the end portion where an antireflection film 18 is formed, and the reflected light again enters the waveguide 12. An interference light of this reflected light and the light which was reflected by the end face enters a photodetector 50. On the basis of its intensity, the displacement of the object 80 is detected by a displacement detecting part 70. In the initial state that the object is not displaced, an electric field is applied to the waveguide 12 via an electrode 15, and the phase difference between the two lights which form the interference light is set to beπ/2. Thereby the sensitivity of interference light intensity to the displacement is made maximum.
|
