Abstract: A method for wireless power transmission in a system comprising a power transmitter which in turn comprises a first light source and means for directing the light emitted by the first light source to a desired direction, and at least one power receiver comprising a first photo-detector for receiving the emitted light and for converting it into electric current. A second light source included in the power transmitter is used for transmitting light around the light emitted by the first light source and substantially parallel to it, the intensity of the light being lower than that of the light emitted by the first light source. A second photo-detector included in the power receiver is used for detecting the light emitted by the second light source and for transmitting a control signal to the power transmitter in response to a successful reception of the light emitted by the second light source.

Abstract: A method for wireless power transmission in a system comprising a power transmitter which in turn comprises a first light source and means for directing the light emitted by the first light source to a desired direction, and at least one power receiver comprising a first photo-detector for receiving the emitted light and for converting it into electric current. A second light source included in the power transmitter is used for transmitting light around the light emitted by the first light source and substantially parallel to it, the intensity of the light being lower than that of the light emitted by the first light source. A second photo-detector included in the power receiver is used for detecting the light emitted by the second light source and for transmitting a control signal to the power transmitter in response to a successful reception of the light emitted by the second light source.

Abstract: A method for controlling a wireless, low-power radio frequency network, and a control device, the network comprising a control device arranged as a master device and at least one slave device subordinated thereto. The master device is arranged to convey control data to the slave device and to receive detection data from the slave device. A data transmission connection is established between the master device and an external terminal via a second telecommunication network, in the master device the received detection data are arranged into a format required by the data transmission protocol used in the data transmission connection to be forwarded to the external terminal and control data from the external terminal to the master device for controlling at least one slave device is conveyed in the format required by the data transmission protocol used on the transmission connection.