| A new kind of Approximate Non-diffracting Grating Structured Light (ANGSL) is studied in this paper, where the theories of non-diffracting light and structured light are considered at the same time. The light has characteristics of long focal-depth, narrow strip-width, steady light field, and constant light intensity in non-diffracting rang, etc. Compared with traditional structured light, ANGSL has obvious advantages in high measurement precision, large measurement range, and has the simpler, steadier structure. It is a high quality light which can be used in 3D surface topography measurement with grating projection. It also can be used extensively in fields such as reverse engineering, quality control, biological engineering, machine vision and iatrical diagnose etc, has great application potentiality . The major work in the thesis is showed as following:A new concept of ANGSL and its implementation method are proposed, an optics system with a precise triangular-section prism is set up to produce ANGSL. This method is analyzed and calculated in both interference mode and diffractive mode, and the distribution of the light field is simulated in the non-diffracting range.The implement system of ANGSL is modeling by ZEMAX software in order to validate its feasibility. And also the experimental system is successfully organized. By image processing and feature study for the experimental data, it shows that the experimental result is coherence with theoretical calculation. The advantages of ANGSL in application are explained by comparing with other structured sources.The error analysis is done to ANGSL system by the theoretical study and ZEMAX modeling. Five situations are discussed such as oblique optical source, spherical optical source, bottom angle error, asymmetry bottom angle error, spinal line error of the triangular-section prism. And this research can be used in correcting and directing the experiment process. |
