Spectral effects in photoelasticity

ABSTRACT We found that any uniform stressed area in loaded birefringent material observed in a polarized, dispersed light shows an extinction effect (black fringes) for different light wavelength A. The shape, speotral position of the fringes and their number depends on value of the stress. The analysis and explanation of the effect were done. The laboratory, computer aided spectrometer was build for making precise measurements for different loading conditions; the results of the measurements are described. The application of the effect as an uniaxial force sensor is proposed.