A method and apparatus are provided for detecting activation of a touch panel. The method includes the steps of providing an N by M touch panel including a matrix of N rows of touch elements along a first axis and M columns of touch elements along a second axis, providing N optical beams where a characteristic of each beam of the N beams is different than the corresponding characteristic of any other of the N optical beams, where the summation of a characteristic any first group of the N optical beams is different than the summation the corresponding characteristic of any other N beams and where each respective beam of the N optical beams corresponds to an input of each of the N rows; and summing the characteristic from an output of each of the N rows.