A diffraction grating in silicon with 50 nm lines and spaces is illuminated with diffraction‐born evanescent waves from its transparent replica. A rotation &fgr; between the gratings results in a set of fringes with period &lgr;fthat is larger than the period of the original gratings by a magnification factorM. These fringes are induced and observed with a photon tunneling microscope having an incident illumination of 650 nm in air. This super‐resolution by what may be considered a form of optical heterodyning with evanescent waves is discussed. ©1995 American Institute of Physics.