レーザー干渉計による伸縮計・ひずみ地震計の Calibration について

Abstract

The use of a laser interferometer has been one of the most successful technique for calibratingextensometers and strain seismometers. We have calibrated horizontal extensometers and strainseismometers installed at the Donzurubo Observatory and the Amagase Station using a Michelsoninterferometer with a He-Ne gas laser source. The sensitivity of these instruments have been de-termined by comparing the absolute displacement, measured by the motion of interferometricimages, with the recorded output amplitude of ordinary observing system.