Measurement optimum condition of speckle interferometry based on dual-camera technique

The speckle interferometer based on multi-camera technology using two cameras is applied to a dynamic deformation measurement of the package of an electronic device. To perform high precise measurement by this method, the optimum conditions for measurements are discussed concerning the size of speckle and the frequency of carrier signals. Under the optimum conditions, the deformation process of the package during the operation of an operational amplifier is measured. Then, the local maximum deformation can be estimated as 150 nm from experimental results. From the results, it can be also confirmed that electronic devices are deformed by the stress of a heat by an operation every second during the operating time.