Research Papers

Robust estimation of tear film surface quality in lateral shearing interferometry

[+] Author Affiliations
Dorota H. Szczesna

Wroclaw University of Technology, Institute of Physics, Wybrzeze Wyspianskiego 27, Wroclaw, 50-370, Poland and Queensland University of Technology, School of Optometry, Victoria Park Road, Kelvin Grove, Brisbane, Queensland 4059, Australia

D. Robert Iskander

Queensland University of Technology, School of Optometry, Victoria Park Road, Kelvin Grove, Brisbane, Queensland 4059, Australia

J. Biomed. Opt. 14(6), 064039 (December 28, 2009). doi:10.1117/1.3275474
History: Received August 14, 2009; Revised October 12, 2009; Accepted October 20, 2009; Published December 28, 2009; Online December 28, 2009
Text Size: A A A

Interferometry is a sensitive technique for recording tear film surface irregularities in a noninvasive manner. At the same time, the technique is hindered by natural eye movements resulting in measurement noise. Estimating tear film surface quality from interferograms can be reduced to a spatial-average-localized weighted estimate of the first harmonic of the interference fringes. However, previously reported estimation techniques proved to perform poorly in cases where the pattern fringes were significantly disturbed. This can occur in cases of measuring tear film surface quality on a contact lens on the eye or in a dry eye. We present a new estimation technique for extracting the first harmonic from the interference fringes that combines the traditional spectral estimation techniques with morphological image processing techniques. The proposed technique proves to be more robust to changes in interference fringes caused by natural eye movements and the degree of dryness of the contact lens and corneal surfaces than its predecessors, resulting in tear film surface quality estimates that are less noisy.

Figures in this Article
© 2009 Society of Photo-Optical Instrumentation Engineers

Citation

Dorota H. Szczesna and D. Robert Iskander
"Robust estimation of tear film surface quality in lateral shearing interferometry", J. Biomed. Opt. 14(6), 064039 (December 28, 2009). ; http://dx.doi.org/10.1117/1.3275474


Tables

Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging & repositioning the boxes below.

Related Book Chapters

Topic Collections

PubMed Articles
Advertisement
  • Don't have an account?
  • Subscribe to the SPIE Digital Library
  • Create a FREE account to sign up for Digital Library content alerts and gain access to institutional subscriptions remotely.
Access This Article
Sign in or Create a personal account to Buy this article ($20 for members, $25 for non-members).
Access This Proceeding
Sign in or Create a personal account to Buy this article ($15 for members, $18 for non-members).
Access This Chapter

Access to SPIE eBooks is limited to subscribing institutions and is not available as part of a personal subscription. Print or electronic versions of individual SPIE books may be purchased via SPIE.org.