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Measurement Method of Height of White Light Scanning Interferometer using Deep Learning

Deep Learning을 사용한 백색광 주사 간섭계의 높이 측정 방법

  • Baek, Sang Hyune (Dept. of Computer Eng., Graduate School, Ajou University) ;
  • Hwang, Wonjun (Dept. of Computer Eng., Graduate School, Ajou University)
  • Received : 2018.07.10
  • Accepted : 2018.07.26
  • Published : 2018.08.31

Abstract

In this paper, we propose a measurement method for height of white light scanning interferometer using deep learning. In order to measure the fine surface shape, a three-dimensional surface shape measurement technique is required. A typical example is a white light scanning interferometer. In order to calculate the surface shape from the measurement image of the white light scanning interferometer, the height of each pixel must be calculated. In this paper, we propose a neural network for height calculation and use virtual data generation method to train this neural network. The accuracy was measured by inputting 57 actual data to the neural network which had completed the learning. We propose two new functions for accuracy measurement. We have analyzed the cases where there are many errors among the accuracy calculation values, and it is confirmed that there are many errors when there is no interference fringe or outside the learned range. We confirmed that the proposed neural network works correctly in most cases. We expect better results if we improve the way we generate learning data.

Keywords

References

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