On Measurement of Three Dimensional Deformation Using Moire Method and Light Slicing Method

Abstract

Methods of photographing orthographic projections of a grating and a contour on a curved surface were proposed. In photographing a contour, a sheet of light is projected on an object intermittently and the object is moved so that its surface may be swept by the sheet, while a camera is focused at the sheet. The contour obtained in this way corresponds to what would be observed from direction of movement of the object. In photographing a grating, a sheet of light is projected continuously. These methods can be applied to any object regardless of its size, whereas in the usual methods using the tele-centric system, spread of region to be photographed is restricted by the aperture of the field lens. Some related methods of measuring shape using Young's interference fringes were modified in similar way. Further, a procedure of measurement of strain in the three dimensional deformation of sheet bulging was shown.