Answers are grounded in this paper and cite their sources.
An acoustooptic cell frequency-shifts 632.8-nm radiation reflected off moving low-reflectivity surfaces. Surface asperities produce phase shifts in an 80-MHz carrier frequency. Surface profile plots and quality parameters are obtained by analyzing digitized phase shifts. Rigid samples may be turntable mounted, and flexible web samples are moved over a smooth stationary guide. A spatial resolution of 1 μm and a vertical resolution of 1 nm are obtained. Reproducibility of rms measurements is also within 1 nm.
No takes yet. Share an insight, caveat, or question.
Peterson et al. (1984) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: