A novel approach based on scanning tunneling microscopy controlled field emission with microlens to form an exceptionally high brightness electron source and low aberration electron probe forming system has been explored. Electron optical studies of such a microsource have shown it to have a brightness two to three orders of magnitude greater than conventional field emission sources at energies in the low keV range and the ability to form an ultrahigh resolution probe with diameter in the 1 to 10 nm range in conjunction with additional microlenses. Encouraging preliminary experimental results have been obtained.