Self adjustable daylight sensor for lighting systems

This paper describes a concept of a daylight sensor, which maintains its dimming function constant regardless the changes to the objects placed in the room. The existing and commercially available sensors are strongly affected by the surface reflectance of the furniture in the rooms. However the proposed sensor, with its logic circuit, ensures daylight dimming not affected by the highly reflective furniture. This paper presents the principle of the sensor's operation supported by numerical results obtained from lighting design software DIALux. The logic process performed in the microcontroller is also explained. Finally results from testing of a prototype are discussed and compared to the action of a commercially available sensor. It is concluded that the newly proposed sensor offers very good stability of the dimming function and it is not affected by the highly reflective objects and furniture introduced to the room.