Optical measurements of the electric field of pulsed streamer discharges in water

The electric field of a streamer tip of a pulsed streamer discharge in water has been investigated by an optical measuring method. Crossed polarizers were used for the measurement of the electric field using the Kerr effect. Pulsed power with a 300 ns pulse width and 53 kV peak voltages was applied to a pin electrode with a Blumlein circuit. The electric field is obtained from the intensity of the laser beam passing through the second polarizer. The beam intensity was recorded by a highspeed camera with an exposure time of 100 ns. The electric field of the streamer tip, which could not propagate any further, was 320 kV/cm.