Remote sensing of ESD through optical and magnetic radiation fields

The optical radiation and the magnetic field generated by electrostatic discharges are measured, together with their current signatures. The observations show that during the initial growth, the temporal variation of the optical pulse is similar to that of the current. The two waveforms deviate from each other during the decaying part of the discharge, the optical signal having a longer duration. The peak current is linearly correlated with a correlation coefficient of 0.9, to the peak optical radiation. The measured currents were used to calculate the magnetic fields and a good agreement was observed between the measurements and calculations. The results show that both the optical radiation and the magnetic field can be used to sense remotely the currents in electrostatic discharges.