A method for testing a plurality of electronic devices formed on a large area substrate is described. In one embodiment, the method includes transferring a substrate on an end effector relative to a testing platform having a plurality of testing columns coupled thereto, the substrate having a plurality of electronic devices located thereon, and moving the substrate in a single directional axis relative to an optical axis of each of the plurality of testing columns, the single directional axis being substantially orthogonal to the optical axis to define a test area on the substrate, wherein the test area is configured to cover an entire length or an entire width of the substrate such that the testing columns are capable of testing the entire substrate as the substrate is moved through the test area.