  Role of the normal polarization in the far-field subwavelength imaging
granted by a dielectric microsphere or microcylinder is discussed and the
hypotheses explaining this experimental fact are suggested. One of these
hypotheses is confirmed by exact numerical simulations. This mechanism of the
magnifying superlens operation is based on the excitation of creeping waves at
a curved dielectric interface by a normally polarized dipole. The set of
creeping waves after their ejection from the surface creates an imaging beam
which may mimic either a Bessel beam or a Mathieu beam depending on the
microparticle radius. This mechanism corresponds to the asymmetric coherent
illumination.
