Abstract: New exemplary systems using a laser beam generated by a transmitter unit in abase station, for detecting, communicating with and controlling devices, typically battery-operated, installed in public spaces. Interaction between the laser beam and the device uses a laser detector module on the device, selected to emit a fluorescent signal when the laser beam impinges thereon. A fluorescence detector is installed on the base station, and it detects the incoherent fluorescence emitted by the device when the laser impinges on the device. A wireless data link can implement the exchange of information and instructions between the base station and the device, that may be needed following positive detection of the fluorescent emission from the device. The system may use a laser beam in the short wavelength infra-red (SWIR) region. The detector may provide the device with power for its operation and/or for keeping an installed battery charged.