DCM Phase-Gradient Extraction Technique and its Application in Photodynamic Patterns''s Information Recognition
DCM 相位梯度提取技术在光力学图像信息识别中的应用

In this paper, an approach of computing pixel-by-pixel gradients of optical directly from digitally encoded Fourier-transform or phase-stepped fringe patterns is used in the information recognition of Photodynamic fringe pattern. This approach can be classified as a sine-cosine demodulation technique that finds its roots in the differential cross-multiplier phase-demodulation technique commonly used by the optical fiber sensor community. This technique is algorithmically simple, does not rely on a computation of the arctangent, and therefore is not subject to some of the limitations of the standard phase-unwrapping methodologies. The validity of the proposed phase-gradient technique is demonstrated by the calculation of the stress field of three point bending model using Isodyne method combined with Fourier transform fringe interpretation and the calculation of the contact stress of a plate by using phase-stepping Isodyne method of four maps.