We show how Newton's rings manifest themselves in near-field scanning optical microscopy and discuss how this effect can be used with topographic imaging to measure correlated roughness of thin films. In conventional optics, transmission through a thin nonabsorbing film depends on film thickness when multiple reflectionsfrom the film boundaries are coherent. Measurements and modeling of the transmission through thin films illuminated by a near-field probe show that these oscillations are present despite the large distribution of transverse wavevectors needed to describe light from the probe.
Citation: Applied Physics Letters
Issue: No. 5
Pub Type: Journals
Correlated roughness, microscopy, near-field optics, near-field scanning optical microscopy, NSOM