カラー光弾性皮膜法によって得られた等色線縞の増倍・抽出

抄録

The authors have previously proposed a basic method for multiplying the original isochromatics obtained from a photoelastic experiment and extracting the isochromatics using the original- or multiplied-isochromatic image. In this study, the method is applied to isochromatics obtained using the color photoelastic coating method. The method uses R, G and B fringes, which are taken using a color CCD camera in dark- and light-field circular polariscopes with a white light. The light intensities in the dark-field image are subtracted from those in the light-field image, and the points with zero values are extracted. The fringe orders are assigned to the extracted isochromatics using calibration curves, which shows the relationships between the fringe orders obtained using a single wavelength and those using R, G and B filters in the CCD camera. The method is applied to isochromatics obtained in an aluminum T-shaped plate subjected to a bending load. As a result, continuous isochromatics with a width of one pixel increased by 2, 4 and 6 times are accurately extracted.