AUTOMATIC ILLUMINATION INTENSITY CONTROL DEVICE

摘要

PROBLEM TO BE SOLVED: To improve the visual environment of a room without extra manpower by comprising a controller which changes the light output of a lighting fixture, and measures the illuminance by the external light such as the daylight or the like in the irradiated space, and the illuminance of the irradiated space in the maximum light output of the lighting fixture on the basis of the measurement values of the illuminance sensor in the cases where the light output of the lighting fixture is high and the same is low. SOLUTION: A controller 1 controls the constant illuminance of the irradiated space by sending a modulated light control signal to a lighting fixture 9 on the basis of a sensor signal from an illuminance sensor 6. That is, in a central processing unit of the controller 1, an amplified sensor signal is compared with a target level preset in a memory, and the level of the control signal is increased to the bright side for lightening the lighting fixture 9 when the sensor signal is low on the basis of the result of the comparison. Further the level of the control-signal is decreased to the dark side for darkening the lighting fixture 9 when the sensor signal is high. Whereby the adjustment of the illuminance can be automatically performed.