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(11) | EP 1 528 841 A3 |
(12) | EUROPEAN PATENT APPLICATION |
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(54) | Lighting control |
(57) A lighting system is controlled by lighting control apparatus 40 dependent on a received
input signal 41 representing a required perceived illumination level. The lighting
control apparatus comprising a sigma-delta converter having an input filter 47 for
providing a filtered input signal 411 from the input signal 41 to a precision comparator
44 for comparing the filtered input signal with a feedback input signal 451 from a
system model module 45 simulating an effect of the input signal on the lighting system.
A resultant perceived illumination level is compared with the required perceived illumination
level, and the precision comparator provides an output signal 42 for controlling a
power supply 43 to the lighting system 46 to provide the required perceived illumination
level. |