Modulating retroreflective piezoelectric multilayer film

A label comprising:

• a modulating retroreflective multilayer film comprising:
• retroreflective elements;
• a piezoelectric layer having opposing top and bottom surfaces;
• a first electrode layer in electrical connection with the top surface of the piezoelectric layer;
• a second electrode layer in electrical connection with the bottom surface of the piezoelectric layer;
• a voltage source located within a layer of the multilayer film and being in electrical connection with the first and second electrode layers;
• a processor located within a layer of the multilayer film and being communicably coupled with the voltage source to apply a voltage across the piezoelectric layer;
• an energy storage device located within a layer of the multilayer film and being configured to store energy used for the applying of the voltage;
• and
• a photovoltaic layer communicably in electrical connection with the energy storage device and coupled with the processor to transmit electrical signals to the processor;
• and
• one or more adhesive layers,
• wherein one of the one or more adhesive layers is an outer adhesive layer located at an end of the multilayer film.

A method for modulating retroreflected light, the method comprising:

• providing a modulating retroreflective multilayer film comprising:
• retroreflective elements;
• a piezoelectric layer having opposing top and bottom surfaces;
• a first electrode layer in electrical connection with the top surface of the piezoelectric layer;
• a second electrode layer in electrical connection with the bottom surface of the piezoelectric layer;
• a voltage source located within a layer of the multilayer film and being in electrical connection with the first and second electrode layers;
• a processor located within a layer of the multilayer film and being communicably coupled with the voltage source to apply a voltage across the piezoelectric layer;
• an energy storage device located within a layer of the multilayer film and being configured to store energy used for the applying of the voltage;
• and
• a photovoltaic layer communicably in electrical connection with the energy storage device and coupled with the processor to transmit electrical signals to the processor
• illuminating the film with an incident light beam;
• retroreflecting the incident light beam into a reflected light beam via a first configuration of retroreflective elements;
• detecting the incident light beam with the photovoltaic layer;
• transmitting a signal from the photovoltaic layer to the processor;
• applying a voltage across the piezoelectric layer to change a dimension of the piezoelectric layer to form a second configuration of retroreflective elements;
• and
• retroreflecting the incident light beam into a modulated light beam via the second configuration of retroreflective elements.