Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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A Measurement Method of Three-Dimensional Surface Morphology Based on Depth-from-Focus through Linear Magnification Calibration

선형배율보정을 통한 DFF 기반의 삼차원 형상 측정법

  • 김경범 (충주대학교 기계설계학과) ;
  • 신영수 (충주대학교 대학원 기계설계학과)
  • Published : 2005.09.01
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Abstract

Errors resulting from magnification variations of a optical system are largely generated in three-dimensional shape measurements based on depth-from-focus. In the case of measuring the surface morphology of tiny objects based on DFF, images are acquired with a very small interval so that magnification changes can be minimized. However, the magnification variations are actually existed in the acquired images and so focus measures are wrongly or ambiguously extracted. In this paper, a methodology with linear magnification calibrations, based on DFF, is proposed to make more accurate measurement in surface morphology with high depth discontinuity, compared with previous ones. Several experiments show that the proposed method outperforms existing ones without magnification calibrations.

Keywords

References

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