Patent ID: 7659495

Claim:
An auto darkening eye protection device comprising: a shutter assembly adjustable between a clear state and a dark state; a control circuit comprising: a sensing circuit having at least one photodetector sensing an occurrence of a welding arc and providing an output indicative of the occurrence of the welding arc, the sensing circuit also including a feedback circuit regulating the amount of current passing through the at least one photodetector; a weld detect circuit receiving the output of the sensing circuit, the weld detect circuit enabling a dark state drive signal to be delivered to the shutter assembly; and a delivery circuit outputting the dark state drive signal to the shutter assembly to switch the shutter assembly from the clear state to the dark state upon enablement by the weld detect circuit; and a power supply supplying power to the control circuit, the power supply comprising: a power regulation circuit; a solar power supply supplying power having an unregulated voltage to the sensing circuit and the power regulation circuit; and a battery power supply supplying power having a voltage to the power regulation circuit; and wherein the power regulation circuit regulates the unregulated voltage of the solar power supply above the voltage of the battery power supply whereby the solar power supply is preferably used to supply regulated power to the control circuit when the shutter assembly is in the dark state.