Patent ID: 8742347
Filing Date: 2014-06-03
Classification: G01J,G01N,G01R

Abstract:
1. A method for detecting the location of heat sources buried within a sample by using Lock-in Thermography, comprising: placing the sample on a test system; applying test signals to the sample at a lock-in frequency; while the test signals are applied to the sample, imaging the sample using an infrared sensor; detecting from the imaging lateral temperature distribution on a surface of the sample, to thereby spatially localize a hot spot; reducing the field of view of the infrared sensor to a small area around the center of the hot spot; increasing the operational speed of the infrared sensor; imaging the sample using the reduced field of view and increased operational speed of the infrared camera; calculating plurality of mean values across the reduced field of view in synchronization with the test signal lock-in frequency; and, analyzing the plurality of mean values to thereby determine depth location of the hot spot within the sample.