a method of economically manufacturing display devices having a matrix of drivable pixels arranged in rows and columns arranged to be driven by ic drivers , including the steps of including a plurality of sensor signal lines in the display device that are selectively connectable to certain of the pixel rows , a plurality of sensor signal lines selectively connectable to certain of the pixel columns , transmitting test signals to test predetermined ones of the rows and columns of pixels , and connecting pixel driving circuits to those display devices exhibiting uniform pixel brightness in response to the test signals .