Corneal group refractive index measurement using low-coherence interferometry

Stephen R. Uhlhorn, Fabrice Manns, Hassan Tahi, Pascal Rol, Jean-Marie A Parel

Research output: Chapter in Book/Report/Conference proceedingConference contribution

11 Citations (Scopus)

Abstract

Purpose. The goal of the study is to measure the group refractive index of the human cornea in vitro to improve the accuracy of corneal thickness measurements. Methods. Corneal buttons were trephined from 23 human cadaver eyes and the group refractive index of the cornea was measured at λ = 840 nm using a low-coherence Michelson interferometer and the technique proposed by Sorin and Gray (Phot. Tech. Lett. 4:105-107, 1992). The effect of dehydration on the measurement was studied by measuring the corneal optical thickness as a function of time. Results. Preliminary measurements of the group refractive index at 840 nm gave n g = 1.450 +/- 0.024 for the human cornea, which is much higher than a calculated group refractive index of n g = 1.387. Because of dehydration, the optical thickness of the cornea decreased at a rate of 5.5 μm/min which led to an artificially high value for the group refractive index. Conclusion. The calculated group refractive index of n g = 1.387 appears to be an accurate value for the purpose of corneal thickness measurements using low-coherence interferometry, and corneal group refractive index measurements can be performed in vitro if the measurements are performed rapidly to avoid the effect of dehydration.

Original languageEnglish (US)
Title of host publicationProceedings of SPIE - The International Society for Optical Engineering
EditorsP.O. Rol, K.M. Joos, F. Manns, A. Katzir
Pages14-21
Number of pages8
Volume3246
DOIs
StatePublished - 1998
EventProceedings of Ophthalmic Technologies VIII - San Jose, CA, United States
Duration: Jan 24 1998Jan 25 1998

Other

OtherProceedings of Ophthalmic Technologies VIII
CountryUnited States
CitySan Jose, CA
Period1/24/981/25/98

Fingerprint

Interferometry
Refractive index
interferometry
refractivity
cornea
Dehydration
dehydration
Thickness measurement
optical thickness
buttons
Michelson interferometers

Keywords

  • Cornea
  • Low-coherence interferometry
  • Refractive index

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Condensed Matter Physics

Cite this

Uhlhorn, S. R., Manns, F., Tahi, H., Rol, P., & Parel, J-M. A. (1998). Corneal group refractive index measurement using low-coherence interferometry. In P. O. Rol, K. M. Joos, F. Manns, & A. Katzir (Eds.), Proceedings of SPIE - The International Society for Optical Engineering (Vol. 3246, pp. 14-21) https://doi.org/10.1117/12.309424

Corneal group refractive index measurement using low-coherence interferometry. / Uhlhorn, Stephen R.; Manns, Fabrice; Tahi, Hassan; Rol, Pascal; Parel, Jean-Marie A.

Proceedings of SPIE - The International Society for Optical Engineering. ed. / P.O. Rol; K.M. Joos; F. Manns; A. Katzir. Vol. 3246 1998. p. 14-21.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Uhlhorn, SR, Manns, F, Tahi, H, Rol, P & Parel, J-MA 1998, Corneal group refractive index measurement using low-coherence interferometry. in PO Rol, KM Joos, F Manns & A Katzir (eds), Proceedings of SPIE - The International Society for Optical Engineering. vol. 3246, pp. 14-21, Proceedings of Ophthalmic Technologies VIII, San Jose, CA, United States, 1/24/98. https://doi.org/10.1117/12.309424
Uhlhorn SR, Manns F, Tahi H, Rol P, Parel J-MA. Corneal group refractive index measurement using low-coherence interferometry. In Rol PO, Joos KM, Manns F, Katzir A, editors, Proceedings of SPIE - The International Society for Optical Engineering. Vol. 3246. 1998. p. 14-21 https://doi.org/10.1117/12.309424
Uhlhorn, Stephen R. ; Manns, Fabrice ; Tahi, Hassan ; Rol, Pascal ; Parel, Jean-Marie A. / Corneal group refractive index measurement using low-coherence interferometry. Proceedings of SPIE - The International Society for Optical Engineering. editor / P.O. Rol ; K.M. Joos ; F. Manns ; A. Katzir. Vol. 3246 1998. pp. 14-21
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