Popular electrospun technology can only obtain submicron fibers and fiber membranes in random or in slight orientation, in fact, they are not real nanofibers. A fast-rotating drum-collector has been introduced into the electrospinning setup to improve the orientation of electrospun fibers/membranes and, more importantly, to stretch the electrospun fibers. The measured results indicate that: (1) the submicro-fiber orientation and the angle frequency distribution can be characterized quantitatively by Hough transform (HT) and Regionprops function (RF) approaches, and the accuracy of HT is relatively higher than that of RF; (2) through changing the drum speed, an extra stretching force is exerted on the submicro-fibers, so making them thinner; and (3) the higher the drum surface speed, the greater is the orientation of the electrospun fibers, and the finer and stronger the submicro-fibers; their diameter ranges from about 250 nm at zero drum speed to 170 nm at 7 m/min, and may even get into the nanoscale-that is, 1-100 nm.