Topographic characterization of unworn contact lenses assessed by atomic force microscopy and wavelet transform

Ştefan Ţălu; Krzysztof StȨpień; Mustafa Oguzhan Caglayan

doi:10.1002/jemt.22580

Topographic characterization of unworn contact lenses assessed by atomic force microscopy and wavelet transform

Microsc Res Tech. 2015 Nov;78(11):1026-31. doi: 10.1002/jemt.22580. Epub 2015 Sep 21.

Authors

Ştefan Ţălu¹, Krzysztof StȨpień², Mustafa Oguzhan Caglayan³

Affiliations

¹ Faculty of Mechanical Engineering, Department of AET, Discipline of Descriptive Geometry and Engineering Graphics, Technical University of Cluj-Napoca, 103-105 B-Dul Muncii St., Cluj-Napoca 400641, Cluj, Romania.
² Department of Manufacturing Engineering and Metrology, Faculty of Mechatronics and Mechanical Engineering, Kielce University of Technology, Aleja 1000-Lecia Państwa Polskiego 7, Kielce, 25-314, Poland.
³ Nanotechnology Engineering Department, Cumhuriyet University, Sivas, 58140, Turkey.

PMID: 26389706
DOI: 10.1002/jemt.22580

Abstract

This paper analyses the three-dimensional (3-D) surface morphology of optic surface of unworn contact lenses (CLs) using atomic force microscopy (AFM) and wavelet transform. Refractive powers of all lens samples were 2.50 diopters. Topographic images were acquired in contact mode in air-conditioned medium (35% RH, 23°C). Topographic measurements were taken over a 5 µm × 5 µm area with 512 pixel resolution. Resonance frequency of the tip was 65 kHz. The 3-D surface morphology of CL unworn samples revealed (3-D) micro-textured surfaces that can be analyzed using (AFM) and wavelet transform. AFM and wavelet transform are accurate and sensitive tools that may assist CL manufacturers in developing CLs with optimal surface characteristics.

Keywords: Fast Fourier Transform; atomic force microscopy; contact lenses; surface morphology; wavelet transform.

MeSH terms

Contact Lenses*
Microscopy, Atomic Force*
Surface Properties*
Wavelet Analysis