Measurement of residual stress for ITO/PET substrates by the double beam shadow moire interferometer

This study constructed a measurement system that can quickly and accurately analyze the residual stress of flexible electronics. A double beam shadow moire interferometer was set up to measure and evaluate the residual stress of tin-doped indium oxide films on a polyethylene terephthalate substrate. However, this system required only two symmetrical fringes to evaluate the residual stress of transparent conductive oxide films on flexible substrate. Applying the grating translation techniques to the double beam shadow moire interferometer greatly improved the measurement resolution and accuracy, and the relative error was reduced to 1.2%. (C) 2012 Optical Society of America