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Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 49, Iss. 15 — May. 20, 2010
  • pp: 2920–2928

Full-field optical thickness profilometry of semitransparent thin films with transmission densitometry

Jay Johnson and Tequila Harris  »View Author Affiliations

Applied Optics, Vol. 49, Issue 15, pp. 2920-2928 (2010)

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A novel bidirectional thickness profilometer based on transmission densitometry was designed to measure the localized thickness of semitransparent films on a dynamic manufacturing line. The densitometer model shows that, for materials with extinction coefficients between 0.3 and 2.9 D / mm , 100 500 μm measurements can be recorded with less than ± 5 % error at more than 10,000 locations in real time. As a demonstration application, the thickness profiles of 75 mm × 100 mm regions of polymer electrolyte membrane (PEM) were determined by converting the optical density of the sample to thickness with the Beer–Lambert law. The PEM extinction coefficient was determined to be 1.4 D / mm , with an average thickness error of 4.7%.

© 2010 Optical Society of America

OCIS Codes
(120.1840) Instrumentation, measurement, and metrology : Densitometers, reflectometers
(310.6845) Thin films : Thin film devices and applications

ToC Category:
Thin Films

Original Manuscript: February 16, 2010
Revised Manuscript: April 15, 2010
Manuscript Accepted: April 19, 2010
Published: May 19, 2010

Jay Johnson and Tequila Harris, "Full-field optical thickness profilometry of semitransparent thin films with transmission densitometry," Appl. Opt. 49, 2920-2928 (2010)

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