Anti-reflective coatings on camera lenses and glasses work by utilizing thin-film interference to greatly reduce reflected light. (Ever wondered why your glasses have a bluish/magenta tint when they reflect light? It's from that thin film!) We wish to coat flat glass (n=1.50) with a transparent material (n=1.25), so that reflection of light at wavelength 402.375nm is eliminated by interference. What is the minimum thickness (nm) of the coating that will work for our purposes?

Anti-reflective coatings on camera lenses and glasses work by utilizing thin-film interference to greatly reduce reflected light. (Ever wondered why your glasses have a bluish/magenta tint when they reflect light? It's from that thin film!) We wish to coat flat glass (n=1.50) with a transparent material (n=1.25), so that reflection of light at wavelength 402.375nm is eliminated by interference. What is the minimum thickness (nm) of the coating that will work for our purposes?

University Physics Volume 3

17th Edition

ISBN:9781938168185

Author:William Moebs, Jeff Sanny

Publisher:William Moebs, Jeff Sanny

Chapter3: Interference

Section: Chapter Questions

Problem 47P: To save money on making military aircraft invisible to radar, an inventor decides to coat them with...

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