Lighting control system for room in building has ring-shaped energy efficient gas discharge lamp surrounding two separate Charged-Coupled Device fields with lenses forming images of parts of room

摘要

The ring-shaped gas discharge lamp (2) for illuminating the room is mounted in a light fitting (1) in the ceiling and has a reflector (2a). Two separate CCD (Charged-Coupled Device) fields (4a,4b) are mounted in the fitting and have lenses (4a1,4b1) to focus images of different parts of the room. The CCDs form part of a room occupation monitor (3) and are connected to an evaluation circuit (5). This circuit is connected to a load regulating circuit (7) which controls the lamp. The monitor is connected to a power supply line (9) and a data transmission line (8).