| 摘要 |
PURPOSE:To detect a deformation strain produced at a minute area, by a method wherein a magnetic garnet, whereon lattice-shaped bubble are formed, is firmly adhered to an object to be measured to detect an extinction magnetic field value of a magnetic valve. CONSTITUTION:A garnet chip 3 is firmly adhered to an object to be measured by the use of a silicon adhesive agent so that no adhesion strain is produced. A uniaxial anisotropic magnetic field Hk is caused to act on the chip 3 beforehand to form a large number of lattic-shaped bubble, and the Hk and an extinction magnetic field Ho are measured. While a magnetic field is being vertically applied to the chip surface, the extinction magnetic field Ho is measured over a-b using a polarized microscope to find a change amount DELTAHo. The DELTAHo changes in proportion to a stress in a magnetic garnet crystal film, and as a result, a deformation strain of an object to be measured is measured with a position accuracy of several tens mum. |
