Abstract-A new type of high resolution E-field microscope system is described. The system is based on a novel design of an active E-field probe (EFP) probe, which is both nonintrusive and displays high spatial resolution. This paper focuses on the construction and spatial resolution of the probe, which shows significant evolution from that previously reported [1], and some measurements on passive structures which indicate that features smaller than 100 microns can be individually resolved. The probe construction lends itself to further improvements in spatial resolution. Measurement results are presented which demonstrate the high resolution of the probe, and its potential utility in measuring waveforms with high spatial resolution at individual points on microwave circuits, discrete devices, and integrated circuits.