the Hammersley sequence employed to reduce the shot noise to 1/N. Figure 6(b) shows the electron pulse at the detector plane. The wavefront of the electron pulse is no longer flat, and is approximately 60 picoseconds in duration. However, neither of these factors has a negative impact on the imaging capability of the fs-TEM.

Comparing figure 6(a) and (b), there is a fair agreement between radial position and Np when comparing the pulse at the sample and detector. Minor disagreement is found between macroparticles far from the propagation axis, however considering that the majority of the charge lies close to the propagation axis, this distortion affects a small sample of the pulse population and hence will have minimal impact. Magnification of the order of $10^4$ is also evident upon examination of the length scales of the pulses displayed, fulfilling design criteria (1).

Spatial and dynamic electric field resolution
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To fully exploit the imaging capabilities of the fs-TEM, the detection of electromagnetic fields requires quantification. We employ a 3D electric field to investigate the displacement of electron pulses detectable within the fs-TEM. A custom GPT element deflects the passing electron pulse with an electric field, and removes macroparticles from the 