Journal Article10.1364/AO.7.001971
Improved Three-Beam Interferometric Method
R. C. Tyagi,Kehar Singh +1 more
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TL;DR: Three-beam interference has been investigated, in order to obtain an intensity distribution that enables more accurate determination of small phase changes by photometric null setting criterion.
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Abstract: Three-beam interference has been investigated, in order to obtain an intensity distribution that enables more accurate determination of small phase changes by photometric null setting criterion. A phase change in the interfering beam makes the adjacent fringes unequal in brightness as well as in thickness so that the form discrimination property of the eye assists its brightness discrimination property, thereby increasing the accuracy of measurements to lambda/450. A simple experimental arrangement to demonstrate the results of analytical study is presented.
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Citations
Three-beam interferometric profilometer.
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Measurement of focusing properties for high numerical aperture optics using an automated submicron beamprofiler
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•Journal Article
The concept of partial coherence in optics
TL;DR: In this article, it was shown that the diameter of the area of coherence on a plane illuminated by a source of angular radius α is given by d = 0.16λ/N sin α, where N is the refractive index of the intervening medium.
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Generation of phase edge singularities by coplanar three-beam interference and their detection.
TL;DR: This paper presents the first general analysis of formation of phase edge singularities by coplanar three-beam interference, and proposes an automatic fringe pattern analysis technique for detecting phase edge dislocations, based on the continuous wavelet transform.
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Modified photoelectric setting scheme for a three-beam interferometer
TL;DR: A photoelectric detection scheme for a three-beam interferometer that makes use of a relative oscillating motion between the fringes and a slit placed in the interference pattern to produce measurement signals is described.
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References
The setting accuracy in two-beam interferometry
TL;DR: In this paper, the accuracy of some setting methods applicable in two-beam interferometry is investigated with regard to its dependence on the conditions of observation, and it is shown that photometric methods prove to be the most advantageous.
5
Three-beam interferometer
P Hariharan,D Sen +1 more
TL;DR: In this paper, a beam dividing system similar to that used in the Jamin interferometer, but employing three interfering beams instead of two, was used for determination of the fractional fringe order with an extremely high degree of accuracy.
The Concept of Partial Coherence in Optics
TL;DR: In this paper, it was shown that the diameter of the area of coherence on a plane illuminated by a source of angular radius is given by d = d = 0 √ √ n √ 16 λ n N ε, where N is the refractive index of the intervening medium.
A Precision Method for Measuring Small Phase Differences
TL;DR: The well-known diffraction figure of three equidistant slits may be considered as formed by the fringes of equal intensity caused by the outer slits, together with the coherent background from the middle slit, which alternately reinforces and suppresses these fringes.
A new interferometer capable of measuring small optical path differences.
TL;DR: The development of a new type of interferometer capable of measuring optical path differences of lambda/1000 or less and exhibiting an advantage of increased environmental stability over more conventional interferometers which depend upon optical path changes manifested as fringe shifts is reported.