Patent ID: 6201351
Filing Date: 2001-03-13
Classification: H05B,Y10S

Abstract:
A light-sensitive circuit for use with at least one light, the light-sensitive circuit comprising:a resistive network including a photocell, the photocell being responsive to a sensed ambient illumination level and having a threshold illumination associated therewith, the resistive network having an equivalent resistance varying as a function of the sensed ambient illumination level and the threshold illumination level;a firing capacitor responsive to the resistive network and charging to a firing voltage at a rate corresponding to the equivalent resistance;a trigger generating circuit responsive to the firing capacitor and generating a trigger signal in response to the firing capacitor being substantially charged to the firing voltage;an AC power switch responsive to the trigger signal, the AC power switch coupling the AC power signal to the light in response to the trigger signal for a selectable portion of a cycle of the AC power signal, the selectable portion of the cycle of the AC power signal corresponding to a current provided to the light; anda multi-position switch coupled to the light, the light-sensitive circuit, and the AC power signal, the multi-position switch having at least an off position, an on position, and a light-sensitive position, the multi-position switch decoupling the light and the light-sensitive circuit from the AC power signal while in the off position, the multi-position switch coupling the light to the AC power signal while in the on position, and the multi-position switch coupling the light to the AC power signal through the light-sensitive circuit while in the light-sensitive position, the light flickering while a value of the current is within a flicker region, the light-sensitive circuit including a cutoff circuit operatively coupled to the light-sensitive circuit, the cutoff circuit limiting the selectable portion of the cycle of the AC power signal provided to the light such that light will not illuminate while the value of the current is within the flicker region, thereby preventing the light from flickering.