Covert IR-Laser Remote Listening Device

Abstract

This honors thesis details the performance, specifications, and process used in designing and building the Covert IR‐Laser Remote Listening Device (RLD.) In the interests of national security and law enforcement, it is some times necessary to perform covert surveillance of a target. The purpose of this product was to create an inexpensive, novel prototype capable of detecting and recording conversation from behind a window or within an automobile. Our final product utilizes window vibrations to deflect an infrared laser beam reflected off of the window surface. The deflections of this reflected beam cause changes in intensity of the light incident upon the photodetector within our product, and these fluctuations are then reconverted to audible sound. The final design prototype has been used to reliably detect sound from behind a window at ranges up to at least 20 feet in the direct reflection condition. This product is the result of funding by Lockheed Martin Advanced Systems in conjunction with the University of Arizona engineering senior design class.