Miniature light-activated lamp control apparatus and the like

Abstract

Miniature light-activated lamp control apparatus and the like, including a thin disk-shaped switching unit positionable within a light bulb socket and a thin light conductor having one end attached thereto, the light conductor being extendable through the gap between the electrically conductive inner wall of the socket and the electrically conductive outer surface of the bulb base disposed in the socket, and terminating at the opposite end in a lens for gathering ambient or other light. The switching unit has a first contact on one side for engagement with the socket center terminal, and a second contact on an opposing side for engagement with the center terminal of a light bulb. The unit includes a thin circuit board having control circuitry mounted thereon, such circuitry being positioned to occupy available space between the conical bulb base and the circuit board. Also mounted on the circuit board and in light communication with the light conductor is a photodetector electrically coupled to the control circuitry. The control circuitry receives operating power from the lamp through the first contact and is responsive to light communicated through the light conductor to turn the power to the second contact OFF and ON. The circuitry also has provision for gradually applying the power to the bulb (slow start) to extend bulb life, and has a hysteresis response to the incoming light intensity so as to eliminate turn-ON and turn-OFF flicker.