Wavelength-scanning Digital Holographic Method

Surface and internal defects of object are one of the most important reasons causing product quality problems and failures, including micro-cracks, micro-scratches, nano-deposition particles. In order to obtain the multi-layer information of the object, this paper proposes the wavelength-scanning digital holographic method. The algorithm is simulated to analyze the feasibility of acquiring the layered information of objects and the separation effect. Compared with the micro-hologram by compressive sensor, the result shows that digital holographic tomography based on wavelength scanning has a good separation effect on multi-layer object information and defects can be detected clearly.