| 摘要 |
The invention relates to an arrangement for activating one or more light-generating device (2) belonging to a defined space (1) in a contactless fashion when a first person enters the defined space, and to deactivate the light-generating device (2) when the first person, or a last person, leaves the space. The arrangement includes a sound-wave receiving means (5) which when detecting sound waves that lie within a predetermined first frequency band initiates activation of the light-generating device (2) and which initiates deactivation of the light-generating device (2) when no sound waves that lie within the frequency band are detected. The sound-wave receiving means is constructed to detect sound waves of extremely low frequency within a predetermined narrow frequency band (0-5 Hz) and/or variations in air pressure. |
