Analysis of source bus line current of a 20-inch size LCD panel through magnetic near field measurement

A three-dimension (3D) magnetic near field scanning system was developed to measure source bus line current of a 20-inch size LCD panel. The Euler´s angle adjustment mechanism and the laser displacement sensor techniques enabled the accuracy of the X, Y, and Z positioning as 0.03 mm, 0.35 mm and 0.05 mm respectively. The measurement results produced distinct source bus line current result up to almost 90 % of the LCD length for the first time. The measured peak current intensity was within the predicted range. Qualitative agreement was obtained between the calculated and measured current waveforms.