OPTICAL INTERFERENCE MEASUREMENT DEVICE AND DRILL CONTROL METHOD USING OPTICAL INTERFERENCE MEASUREMENT

摘要

PROBLEM TO BE SOLVED: To provide an optical interference measurement device that is capable of accurately obtaining internal information of an object and is suitable for application or the like for accurately measuring a relative position between a specific object and the object, and to provide a drill control method utilizing an optical interference measurement.SOLUTION: An optical interference measurement device includes: a low coherence light source 18 for outputting an irradiation lightε; an optical fiber coupler 26 for dividing the irradiation lightεinto a reference lightαand a measurement lightβ1 and outputting both of them; and a reference mirror part 20 for receiving the reference lightαand reflecting it. The optical fiber coupler 26 multiplexes an object lightβ2 which is a reflection light from a specific part having received the measurement lightβ1 and the reference lightαreflected by the reference mirror part 20, and includes an interference optical analysis part for detecting and analyzing an interference lightγbetween the reference lightαmultiplexed by the optical fiber coupler 26 and the object lightβ2. The reference mirror 20 includes a plurality of staircase mirrors 34 formed with a plurality of reflection surfaces 32(1) to 32(4) in parallel with each other and having a level difference; and a shutter 36 for allowing the reference lightαto reflect by selecting any one of the reflection surfaces 32(1) to 32(4).