Patent ID: 6815652
Filing Date: 2004-11-09
Classification: A61F,G01J

Abstract:
An auto darkening eye protection device comprising:a shutter assembly, the shutter assembly being adjustable to a plurality of shade levels; a light sensing circuit for sensing light from a welding arc and providing an output indicative of the shade level at which the shutter assembly should be operated, the light sensing circuit comprising: a phototransistor operative to receive the light from the welding arc and produce an output representative thereof, the phototransistor being configured for surface mount and having an external base connection connected to the base of the phototransistor; a control circuit configured to receive an input from the light sensing circuit and provide a drive signal to the shutter assembly responsive to said input, the drive signal being operative to drive the shutter assembly to one of said plurality of shade levels; and a solar cell coupled to the light sensing circuit and control circuit for powering same.