Abstract: Provided herein is a modulating retroreflective multilayer film comprising retroreflective elements, a piezoelectric layer, a photovoltaic layer, and an energy storage device. The stacked and transparent layered configuration of the film allows the retroreflective elements and the photovoltaic layer to be simultaneously illuminated by a narrow beam. The low power piezoelectric layer and the energy harvesting of the photovoltaic layer allow the retroreflector to be energetically self-sufficient and suitable for remote deployment. The flexible properties of the component layers allow the retroreflector to be adhered to nonplanar or irregular surfaces for the purpose of labeling and tagging.