Journal ArticleDOI
Surface Profiling by Analysis of White-light Interferograms in the Spatial Frequency Domain
Peter J. de Groot,Leslie L. Deck +1 more
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TLDR
In this article, a scanning white-light interferometer for high-precision surface structure analysis is described, where the interferogram for each of the image points in the field of view is generated simultaneously by scanning the object in a direction perpendicular to the object surface, while recording detector data in digital memory.Abstract:
We describe a scanning white-light interferometer for high-precision surface structure analysis. Interferograms for each of the image points in the field of view of the instrument are generated simultaneously by scanning the object in a direction perpendicular to the object surface, while recording detector data in digital memory. These interferograms are then transformed into the spatial frequency domain and the surface height for each point is obtained by examination of the complex phase as a function of frequency. The final step is the creation of a complete three-dimensional image constructed from the height data and corresponding image plane coordinates. The measurement repeatability is better than 0·5 nm r.m.s. for a surface height range of 100 μm.read more
Citations
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Journal ArticleDOI
Red-Green-Blue wavelength interferometry and TV holography for surface metrology
TL;DR: In this article, the interference pattern is decomposed into its R G B components to evaluate the phase at individual wavelengths and an eight step phase shifting algorithm is used to simplify the application of phase shifting technique in the multiple wavelength system.
Book ChapterDOI
Interference Microscopy for Surface Structure Analysis
TL;DR: In this paper, the principles of interferometric dimensional metrology applied to surface features best viewed in a microscope are considered, and a wide variety of techniques for measuring surface texture, shape, step heights, lateral positions and dimensions, transparent film structure, and the scattering behavior of optically unresolved patterns.
Journal ArticleDOI
Effects of phosphor-based LEDs on vertical scanning interferometry
TL;DR: It is proposed and demonstrated that a constraint on the input to the existing reconstruction algorithm improves the repeatability of the vertical scanning interferometer with a phosphor-based LED.
Journal ArticleDOI
Signal correction by detection of scanning position in a white-light interferometer for exact surface profile measurement.
TL;DR: In order to perform an exact surface profile measurement with a white-light scanning interferometer (WLSI), an actual optical path difference (OPD) changing with time is detected with an additional interferometers in which the light source of the WLSI and an optical band-pass filter are used.
Journal ArticleDOI
Application of white-light scanning interferometer on transparent thin-film measurement
TL;DR: The sources of errors in Fourier amplitude, which include the accuracy of wave number, light source variation in time, and illumination nonuniformity, are investigated and with all these errors reduced, the film thicknesses and refractive indices of four samples measured by white-light interferometry are within 1% of the ellipsometry results.
References
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Journal ArticleDOI
Optical coherence tomography
David Huang,Eric A. Swanson,Charles P. Lin,Joel S. Schuman,William G. Stinson,Warren Chang,Michael R. Hee,Thomas J. Flotte,Kenton W. Gregory,Carmen A. Puliafito,James G. Fujimoto +10 more
TL;DR: OCT as discussed by the authors uses low-coherence interferometry to produce a two-dimensional image of optical scattering from internal tissue microstructures in a way analogous to ultrasonic pulse-echo imaging.
Book ChapterDOI
Optical Coherence Tomography
Eric A. Swanson,J. Izatt,M. Bee,David Huang,Charles P. Lin,Carmen A. Puliafito,Carmen A. Puliafito,James G. Fujimoto +7 more
TL;DR: Optical coherence tomography (OCT) has developed rapidly since its first realisation in medicine and is currently an emerging technology in the diagnosis of skin disease as mentioned in this paper, where OCT is an interferometric technique that detects reflected and backscattered light from tissue.
Journal ArticleDOI
Digital phase-shifting interferometry: a simple error-compensating phase calculation algorithm.
TL;DR: La difference de phase entre les 2 faisceaux interferant varie de maniere connue et on fait des mesures de the distribution d'intensite a travers la pupille correspondant a au moins 3 dephasages differents.
Journal ArticleDOI
Optical coherence-domain reflectometry: a new optical evaluation technique.
TL;DR: An optical evaluation technique is described that is suitable for determining the positions and magnitudes of reflection sites within miniature optical assemblies using the coherence effects exhibited by a broadband optical source and is referred to as optical coherence-domain reflectometry.
Journal ArticleDOI
Three-dimensional sensing of rough surfaces by coherence radar
TL;DR: A three-dimensional sensor designed primarily for rough objects that supplies an accuracy that is limited only by the roughness of the object surface, which differs from conventional optical systems in which the depth accuracy is limited by the aperture.