Comparison of the spherulite shape between adjacent ultrathin sections. Each image is an enlargement of the area containing the spherulites indicated by the yellow arrows in Fig. 4c, with the same field of view. Deformations caused during the preparation of ultrathin sections have been corrected. (a) TEM image extracted from the large-area TEM image. (b) TEM image of the same field of view as (a), from an ultrathin section that has been advanced by 200 nm in the depth direction.