Patent ID: 8853952

Claim:
An optical sensor controlled lighting system comprising: an ambient light sensor responsive to ambient light levels for generating an output signal which is proportional to the ambient light level; a light source having a plurality of operational states; means responsive to the output signal for developing a rate of change signal; means for switching the light source between the plurality of operational states, the means for switching including gain or filtering stages and being responsive to the rate of change signal occurring between unidirectional minimum and maximum rates for switching the light source from one to another of the plurality of operational states and the means for switching being further responsive to the rate of change signal indicating increasing ambient light levels for switching the operational state of the light source to an on state; the means for developing being responsive to an increase in the level of the output signal through a threshold level; and an average value filter connected to receive a signal proportional to the output signal as an input; and at least a first comparator connected to receive the output of the average value filter and the signal proportional to the output signal as inputs to generate a difference signal.