Light source width observation system for the evaluation of the diameter of lightning discharge column

Abstract

To evaluate the diameter of lightning discharge column, a unique image observation system has been developed. The system utilizes a video camera and an array of multi-wires. The wire make the shadow in the image of the light source and from the light intensity profile of the shadow the width of the light source is estimated. By using the dummy light source, good agreement has been obtained in the light intensity profile between observed and the calculated. The resolution was evaluated and found that it is one order enhanced as that evaluated from the image width. The system was successfully utilized to observe the real lightning discharges.