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Journal of the Optical Society of America A

Journal of the Optical Society of America A


  • Vol. 15, Iss. 7 — Jul. 1, 1998
  • pp: 1852–1857

Calculation of thin-film optical constants by transmittance-spectra fitting

Milen Nenkov and Tamara Pencheva  »View Author Affiliations

JOSA A, Vol. 15, Issue 7, pp. 1852-1857 (1998)

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Our investigation uses the film-interference transmittance spectrum in the computer calculation of thin-film thickness t and complex refractive index n*=n-ik. Titanium oxide films of different thicknesses are studied, and a new approach to determine the film thickness and optical constants is proposed. This new approach is based on the use of numerical optimization methods in transmittance-spectra fitting. Various dispersion equations of the finite-power-series type are used to obtain the best fit between transmittance measurements and calculations. The best-fit results for n(λ) and k(λ) are found to agree with dispersion relations that follow from a quantum theory of light absorption.

© 1998 Optical Society of America

OCIS Codes
(070.4790) Fourier optics and signal processing : Spectrum analysis
(120.4530) Instrumentation, measurement, and metrology : Optical constants
(120.5240) Instrumentation, measurement, and metrology : Photometry

Original Manuscript: July 15, 1997
Revised Manuscript: February 4, 1998
Manuscript Accepted: February 12, 1998
Published: July 1, 1998

Milen Nenkov and Tamara Pencheva, "Calculation of thin-film optical constants by transmittance-spectra fitting," J. Opt. Soc. Am. A 15, 1852-1857 (1998)

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