PIPO SHG and PIPO THG data of an aplanospore.
An aplanospore visualized by (a) SHG, (b) THG, and (c) structural image cross-correlation analysis between SHG and THG . The images consist of a summation of images recorded at various polarizations. Specific regions seen in (a, b, c) labeled as (i, ii, iii, iv, v, vi) were analyzed to produce (d, e) PIPO data contour plots and fits. Fitting of (a) PIPO SHG data for regions (i, ii, iii, iv, v, vi) were performed with equation (1) while fitting of (b) PIPO THG data for regions (i, ii, iii, iv, v, vi) were performed with equation (2). The contour plots shown of regions i and ii represent areas of intense SHG signal and no THG signal, regions iii and iv represent areas of intense THG signal and no SHG signal while regions v and vi represent areas of correlated SHG and THG signals.