Abstract
In this study, we used rapid terahertz (THz) time-of-flight (ToF) imaging to identify counterfeit electronics prevalent in the online market. THz-ToF allows the nondestructive reflection imaging of portable electronic devices enclosed by plastic cases with a spatial resolution of 1 mm and a depth range larger than 5 mm. For instance, we could identify a counterfeit solid-state device because there was a striking difference in the internal structure compared with that of an authentic device, although its appearance was similar. It is also possible to authenticate small portable devices with arbitrary shapes, such as earphones; THz-ToF imaging can be applied to authentication from a variety of perspectives. Importantly, our technique is particularly useful for identifying the inappropriate use of integrated circuit (IC) chips, such as controller chips in USB hub devices. THz-TDS images for various portable and wearable devices will be useful for rapid in-line authentication of products and will offer an effective tool for identifying fake electronics and the inappropriate use of IC chips in various equipment.