The Application of Phase-Shifting Technique on

• Main Authors: JINGTANG JAN, 詹景棠
• Other Authors: T.Y.Chen
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/26102631570818407010

碩士 === 國立成功大學 === 機械工程學系 === 87 === Having the advantage of high accuracy, the digital shearography is applied to on-line instant inspecting on optical measurement. With image processing accessed by phase shift method, we can accurately obtain information of full-field phase by mathematical operation. So the digital shearography which combined with phase shift method is a favorable technology of nondestructive testing (NDT). The major purpose of this thesis is to produce a measuring system, mainly including the Michelson shearing mechanism which produces shear deformation measurement, the piezoelectric transducers (PZT) produces phase shift, the servo controller and the image processing system. And the phase map is achieved by using the phase shift technology to calculate the change of specimen before and after force being applied. Besides, we use cellular automata algorithm to proceed phase expansion and examine the influence after applying noise. In addition to introduce the digital shearography, the basic principles of phase shift method and the formation system, we prove the practicability of cellular automata by program simulation. Fnaaly, we use the phase shift method to obtain phase map of Aluminum-alloy circular plate, and proceed phase expansion by cellular automata. But due to the error of instruments and too much noise, the results are not quite ideal.