格子移動機構を備えた投影型モアレトポグラフィ法

抄録

An expression defining the position of contours is re-examined in moiré contouring system of projection type. The newly obtained expression adds a correcting term involving a phase difference between gratings to the expression used conventionally. Based on the physical meaning of this expression, a new attempt of lateral movement of one grating is introduced to the former measuring apparatus. In this new way, several characteristics are given to the moire pattern method. By moving one grating relatively to the other, the following properties are provided to the system.
(1) Any point on the object may be adjusted to coincide with the contour line.
(2) Distance between two points on the surface and the displacement of the object can be obtained by the measurement of the shifted distance of the grating.
(3) Multiplication of contour lines can be performed by the suitable movement of the grating and the multiexposure.
(4) Judgement may be given whether a part is a hill or a valley by observing the direction of movement of the fringes as the grating is shifted.