Research On Hologram Interference Fringe Detection And Analysis System

At present，holographic technology is widely used in modern scientific research andindustrial production. Holographic optical element is the core part of the holographictechnology, and its optical performance directly affects the implementation effect ofholographic technology. For the traditional method of detection on optical performance had acomplex process, low efficiency and great error, this paper designed and implementedhologram interference fringe detection and analysis system. This system adopted double lightpath holographic exposure method to record the interference fringes on holographic opticalelement, and could obtain the optical properties of holographic optical element through thedetection and analysis on the interference fringe image.Due to the interference fringe image obtained in reality often contains all kinds of noise,this will not only cause great difficulties for interference fringe detection and analysis, butalso will seriously affect the accuracy of testing data. The paper compared the differentthreshold segmentation algorithms and image filter algorithms, and adopted median filteralgorithm and Otsu algorithms to achieve the interference fringe image preprocess. Afteranalysis several processing methods of fringe image, an improved edge detection algorithmbased on the Canny operator was proposed. This algorithm could effectively distinguishbetween the low intensity and noise, and improved the accuracy of edge detection. What`smore, this algorithm could automatically calculate the high and low threshold according to theinterference fringe image, and accomplished the automatic detection and analysis. Accordingto the algorithms mentioned above, the algorithms of detection and analysis on theinterference fringe were designed and implemented. Based on Visual C++, the systemsoftware was developed. This software could detect and analyze the interference fringe imageeffectively, get fringe number, fringe cycles, fringe contrast and fringe middle line etc. As aresult, the optical performance of holographic optical element could be obtained.Finally, according to the system software, the test on hologram interference fringedetection and analysis system proved that this system could obtain result well, and met the demands of practical application.