Automatic fringe analysis of two-beam interference patterns for measurement of refractive index and birefringence profiles of fibres

Abstract Automatic fringe pattern analysis is a powerful and inexpensive digital image-processing technique. Two-beam polarizing interference Pluta microscope [Pluta M. Opt Acta 1971;18:661, Pluta M. J Microsc 1972;96:309] is automated by the computer-aid via CCD camera and digital frame grabber. Software program is prepared to deal with the duplicated (separated and overlapped) Microinterferograms produced by two-beam polarizing microscope. It also gives an accurate and fast automatic measurement of refractive index and birefringence profiles for fibres. In this paper, the refractive index and birefringence profiles of two different types of fibres, basalt and polypropylene (PP) fibres are presented. A new method to determine the birefringence profile of fibres from non-duplicated microinterferogram is suggested. The cold drawing process for PP fibres is studied.

[1]  Toyohiko Yatagai,et al.  Multiple‐beam Fizeau fringe‐pattern analysis using Fourier transform method for accurate measurement of fiber refractive index profile of polymer fiber , 2002 .

[2]  W. A. Ramadan,et al.  On the determination of the refractive index of a fibre: I. Skin-core fibre , 1994 .

[3]  W. A. Ramadan,et al.  On the determination of the refractive index of a fibre. II. Graded index fibre , 1995 .

[4]  T. Sokkar,et al.  Refractive index profile of GRIN optical fibre considering the area under the interference fringe shift: II. The mismatching case , 1999 .

[5]  M. Pluta,et al.  Interference microscopy of polymer fibres * , 1972 .

[6]  T Yatagai,et al.  Computer-Aided Speckle Pattern Interferometry , 1983, Other Conferences.

[7]  Jonathan Y. Yao.  Digital image processing and isoclinics , 1990 .

[8]  S. Simmens,et al.  Birefringence Determination in Objects of Irregular Cross-sectional Shape and Constant Weight per Unit Length , 1958, Nature.

[9]  Michel E. Marhic,et al.  Nondestructive refractive‐index profile measurements of clad optical fibers , 1975 .

[10]  T. Sokkar.  Determination of the index profile of a graded-index elliptical optical fiber using multiple-beam microinterferometry , 1991 .

[11]  W. Osten,et al.  An Algorithm for the Fast Derivation of Line Structures from Interferograms , 1988 .

[12]  Krishnamurthi Ramesh,et al.  Comparative performance evaluation of various fringe thinning algorithms in photomechanics , 1995, J. Electronic Imaging.

[13]  A. A. Hamza,et al.  Refractive index profile of polyethylene fiber using interactive multiple‐beam fizeau fringe analysis , 2000 .

[14]  T. Sokkar,et al.  Comparative study on interferometric techniques for measurement of the optical properties of a fibre , 1999 .

[15]  K Andresen,et al.  Fringe-orientation maps and fringe skeleton extraction by the two-dimensional derivative-sign binary-fringe method. , 1994, Applied optics.

[16]  W. B. Gardner,et al.  Nondestructive interferometric measurement of the delta and alpha of clad optical fibers. , 1977, Applied optics.

[17]  A. A. Hamza,et al.  Multiple-beam interference fringes applied to GRIN optical waveguides to determine fiber characteristics. , 1985, Applied optics.

[18]  A. A. Hamza.  A Contribution to the Study of Optical Properties of Fibers with Irregular Transverse Sections , 1980 .

[19]  Terry Yuan-Fang Chen,et al.  Computerized fringe analysis in photomechanics , 1989 .

[20]  T. Sokkar,et al.  Optothermomechanical device for the interferometric characterization of fibers , 2005 .

[21]  Q Yu,et al.  Generalized spin filtering and an improved derivative-sign binary image method for the extraction of fringe skeletons. , 1998, Applied optics.

[22]  M. Pluta.  A Double Refracting Interference Microscope with Continuously Variable Amount and Direction of Wavefront Shear , 1971 .

[23]  T. Sokkar.  Index profile of multilayer fibers of an elliptical cross-section. , 1992, Applied optics.