Weak electric fields in vacuum around conductors like small metallic wires
or tips are observed using a low-energy electron point projection microscop
e operating in interferential mode. Observations are made at room temperatu
re with a sensitivity of a few hundred millivolts per micrometer and submic
rometer spatial resolution. (C) 1999 American Institute of Physics. [S0003-
6951(99)03704-3].