Chin. Phys. B ›› 2013, Vol. 22 ›› Issue (1): 14203-014203.doi: 10.1088/1674-1056/22/1/014203

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Effect of the nonlinearity of CCD in Fourier transform profilometry on spectrum overlapping and measurement accuracy

乔闹生a b, 邹北骥a   

  1. a School of Information Science and Engineering, Central South University, Changsha 410083, China;
    b School of Physics and Electronics, Hunan University of Arts and Science, Changde 415000, China
  • 收稿日期:2012-05-30 修回日期:2012-06-15 出版日期:2012-12-01 发布日期:2012-12-01
  • 基金资助:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61173122, 60970098, 60803024, 90715043, and 61144006) and the Postdoctoral Startup Foundation of Central South University, China (Grant No. 1332/74341016030).

Effect of the nonlinearity of CCD in Fourier transform profilometry on spectrum overlapping and measurement accuracy

Qiao Nao-Sheng (乔闹生)a b, Zou Bei-Ji (邹北骥)a   

  1. a School of Information Science and Engineering, Central South University, Changsha 410083, China;
    b School of Physics and Electronics, Hunan University of Arts and Science, Changde 415000, China
  • Received:2012-05-30 Revised:2012-06-15 Online:2012-12-01 Published:2012-12-01
  • Contact: Zou Bei-Ji E-mail:bjzou@vip.163.com
  • Supported by:
    Project supported by the National Natural Science Foundation of China (Grant Nos. 61173122, 60970098, 60803024, 90715043, and 61144006) and the Postdoctoral Startup Foundation of Central South University, China (Grant No. 1332/74341016030).

摘要: In Fourier transform profilometry (FTP), we must restrain spectrum overlapping caused by the nonlinearity of charge coupled device (CCD) and increase the measurement accuracy of object shape. Firstly, the causes of producing higher-order spectrum components and inducing spectrum overlapping are analysed theoretically, and simple physical explanation and analytical deduction are given. Secondly, aiming to suppress spectrum overlapping and improve measurement accuracy, the influence of spatial carrier frequency of projection grating on them is analysed. A method of increasing the spatial carrier frequency of projection grating to restrain or reduce the spectrum overlapping significantly is proposed. We then analyze the mechanism of how the spectrum overlapping is reduced. Finally, the simulation results and experimental measurements verify the correction of the theory and method proposed.

关键词: spectra overlapping, measurement accuracy, nonlinearity of CCD, Fourier transform profilometry

Abstract: In Fourier transform profilometry (FTP), we must restrain spectrum overlapping caused by the nonlinearity of charge coupled device (CCD) and increase the measurement accuracy of object shape. Firstly, the causes of producing higher-order spectrum components and inducing spectrum overlapping are analysed theoretically, and simple physical explanation and analytical deduction are given. Secondly, aiming to suppress spectrum overlapping and improve measurement accuracy, the influence of spatial carrier frequency of projection grating on them is analysed. A method of increasing the spatial carrier frequency of projection grating to restrain or reduce the spectrum overlapping significantly is proposed. We then analyze the mechanism of how the spectrum overlapping is reduced. Finally, the simulation results and experimental measurements verify the correction of the theory and method proposed.

Key words: spectra overlapping, measurement accuracy, nonlinearity of CCD, Fourier transform profilometry

中图分类号:  (Imaging and optical processing)

  • 42.30.-d
42.30.Kq (Fourier optics) 42.30.Wb (Image reconstruction; tomography)