Method of measuring physical quantity

Abstract

Abstract PURPOSE:To measure physical quantities of an object such as length, distortion, etc. with high accuracy even under the poor circumstances, by forming an image of lattice patterns equally spaced from one another on one end of a multi-core optical fiber and, observing moire fringes formed at the other end of the optical fiber. CONSTITUTION:In the case where the distortion is to be measured under the extremely low temperatures, a test piece 10 having latticed fringe patterns drawn in black-and-white thereon is placed in liquid helium. The image of the fringe patterns 1 is formed by an object lens 2 at one end of an image fiber 3. At this time, if the magnification of the object lens 2 is set in such manner that an interval between the fringe patterns of the formed image is equal to that of core arrays of the optical fiber 3, moire fringes are generated at the other end of the fiber 3. When the test piece 10 is deformed or distorted in the above-described state, the fringe patterns 1 are also deformed and the moire fringes are moved. Accordingly, if the amount of this movement of the moire fringes is arranged to be measured through a television monitor 6 or detected by an image processor 7, the distortion amount of the test piece can be measured with high accuracy even under the poor circumstances.

Inventors

• 👤 Kouji Tsumanuma
• 👤 Sadao Chigira
• 👤 Koji Tanaka

Bibliographic Details