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Faculty Sponsor

Dr. Timothy Grove


Department of Physics

University Affiliation

Indiana University – Purdue University Fort Wayne


Like many kids, I always wondered if there are there really spy technologies. There are many devices that just seem too cool to have any basis in reality, but some devices might be feasible.

The goal of this particular set of experiments is to examine if one can use a laser beam to detect a conversation in an office through use of laser light reflection off a window. The experiments use a Michelson interferometer where one of the mirrors is representative of an office window. The vibrations of the “office window” due to sounds reflecting from it can then be used to detect sound. There are two different experiments we examined. First we examine an ideal version of the experiment in which the sound speaker is placed directly on the “office window”. Then we examined a model version where the sound from the speaker must propagate through air to vibrate the “office window” in a sound proof box. We will present the results of these experiments.


Physical Sciences and Mathematics | Physics

Spy Technologies: Using a Laser to “Listen” to Conversations Trung Hieu

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