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Applied Optics

Applied Optics


  • Editor: James C. Wyant
  • Vol. 47, Iss. 2 — Jan. 10, 2008
  • pp: 157–163

Vector wave analysis for nonnormal incident rays in epimicroscopic refractive index profile measurements

Seung Bum Cho, Cheng Liu, Mats Gustafsson, and Dug Young Kim  »View Author Affiliations

Applied Optics, Vol. 47, Issue 2, pp. 157-163 (2008)

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We have investigated the effects of nonnormal incident rays in calculating the refractive index profile of a dielectric sample using the reflectance measurement data obtained with a scanning confocal epimicroscope and also by solving three-dimensional vector wave equations for linearly polarized light. The numerically calculated reflection data of tightly focused Gaussian beams with different numerical apertures (NAs) on planar surfaces with various refractive indices confirm that the reflectance increases with an increase in the NA of a focusing objective lens. This is due to the nonnormal incident ray components of a Gaussian beam. We have found that the refractive index obtained with the assumption of a normal incident beam is far from the real value when the NA of a focusing lens becomes larger than 0.5, and thus the variation in the reflectance for different angular components in a Gaussian beam must be taken into consideration while using a larger NA lens. Errors in practical refractive index calculation for an optical fiber based on a normal incident beam in reflectance measurements can be as large as 1 % in comparison to real values calculated by our three-dimensional vector wave equations.

© 2008 Optical Society of America

OCIS Codes
(060.2270) Fiber optics and optical communications : Fiber characterization
(060.2300) Fiber optics and optical communications : Fiber measurements
(180.1790) Microscopy : Confocal microscopy

ToC Category:
Fiber Optics and Optical Communications

Original Manuscript: August 15, 2007
Revised Manuscript: October 7, 2007
Manuscript Accepted: November 2, 2007
Published: January 7, 2008

Virtual Issues
Vol. 3, Iss. 2 Virtual Journal for Biomedical Optics

Seung Bum Cho, Cheng Liu, Mats Gustafsson, and Dug Young Kim, "Vector wave analysis for nonnormal incident rays in epimicroscopic refractive index profile measurements," Appl. Opt. 47, 157-163 (2008)

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  1. F. L Pedrotti, L. M. Pedrotti, and L. S. Pedrotti, Introduction to Optics (Academic, 1993).
  2. Y. Youk and D. Y. Kim, "Tightly focused epimicroscope technique for submicrometer-resolved highly sensitive refractive index measurement of an optical waveguide," Appl. Opt. 46, 2949-2953 (2007). [CrossRef] [PubMed]
  3. S. B. Cho, Y. Youk, and D. Y. Kim, "Stable system technique for measuring the refractive index profile of an optical fiber by modified fiber-type confocal microscope method," Proc. SPIE 6469, 646914 (2007).
  4. W. J. Stewart, "A new technique for measuring the refractive index profiles of graded optical fibers," in Technical Digest 1006 of the 1997 International Conference on Integrated Optics and Optical Fiber Communication (IECE, Japan, Tokyo, 1997), pp. 395-398.
  5. W. J. Stewart, "Optical fiber and perform profiling technology," IEEE J. Quantum Electron. QE-18, 1451-1466 (1982). [CrossRef]
  6. K. W. Raine, J. G. Baines, and R. J. King, "Comparison of refractive index measurements of optical fibres by three methods," IEE Proc. 135, 190-195 (1988).
  7. K. W. Raine, J. G. N. Baines, and D. E. Putland, "Refractive index profiling--state of the art," J. Lightwave Technol. 7, 1162-1169 (1989). [CrossRef]
  8. T. Wilson, J. N. Gannaway, and C. J. R. Sheppard, "Optical fibre profiling using a scanning optical microscope," Opt. Quantum Electron. 12, 341-345 (1980). [CrossRef]
  9. J.-X Cheng, A. Volkmer, and X. S. Xie, "Theoretical and experimental characterization of coherent anti-stokes raman scattering microscopy," J. Opt. Soc. Am. B 19, 1363-1375 (2002). [CrossRef]
  10. A. E. Siegman, Lasers (Academic, 1986).
  11. S. Hasegawa, N. Aoyama, A. Futamata, and T. Uchiyama, "Optical tunneling effect calculation of a solid immersion lens for use in optical disk memory," Appl. Opt. 38, 2297-2300 (1999). [CrossRef]
  12. B. Richards and E. Wolf, "Electromagnetic diffraction in optical systems II. Structure of the image field in an aplanatic system," Proc. R. Soc. London , Ser. A 253, 358-379 (1959). [CrossRef]

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