Abstract: A method of transmitting data in a wireless power transmission system comprising a power transmitter including a first and a second light source and means for directing the emitted light. The second light source is used for transmitting, parallel and as low-intensity pulses, light arranged around the light emitted by the first light source, data bits being encoded in the pulses so as to determine a maximum time interval between two successive pulses. At least one power receiver of the system comprises a first and a second photo-detector for receiving the emitted light and for converting it into electric current. The second photo-detector is used for indicating light pulses and data included therein and time between successive light pulses. A control signal indicating disturbance-free reception of data is transmitted to the transmitter if the time between successive light pulses does not exceed a predetermined maximum time interval.

Abstract: A method of transmitting data in a wireless power transmission system comprising a power transmitter including a first and a second light source and means for directing the emitted light. The second light source is used for transmitting, parallel and as low-intensity pulses, light arranged around the light emitted by the first light source, data bits being encoded in the pulses so as to determine a maximum time interval between two successive pulses. At least one power receiver of the system comprises a first and a second photo-detector for receiving the emitted light and for converting it into electric current. The second photo-detector is used for indicating light pulses and data included therein and time between successive light pulses. A control signal indicating disturbance-free reception of data is transmitted to the transmitter if the time between successive light pulses does not exceed a predetermined maximum time interval.

Abstract: A method for transmitting power wirelessly between a power transmitter comprising a light source, means for directing the light emitted by the light source in a desired direction, and means for controlling the intensity of the light emitted by the light source, and at least one power receiver comprising a photo-detector for receiving emitted light and for converting it into electric current. The light source of the power transmitter transmits a parallel light, the intensity of which is substantially less than the allowed maximum eye exposure. The photo-detector of the power receiver detects the light emitted by the light source and determines the integrity of the light beam, and the power receiver transmits a control signal to the power transmitter. The intensity of the light transmitted by the light source of the power transmitter is increased in response to receiving from the power receiver a control signal.

Abstract: A wireless surveillance system that comprises a base station and surveillance devices, such as cameras. The base station comprises a radio frequency transceiver and a power transmitter including a first and second light source and means for directing the first light source in a desired direction. The power of the second light source is substantially lower than that of the first, and it is transmitted parallel around the light emitted by the first light source. The surveillance device comprises a radio frequency transceiver and a power receiver including a first photo-detector for receiving emitted light and a second photo-detector for detecting the light emitted by the second light source. The surveillance device transmits a control signal to the base station, which first switches on the second light source and, in response to the control signal received from the surveillance device, switches on the first light source.