Patent ID: 8181270
Filing Date: 2012-05-22
Classification: A61F,G01J

Abstract:
1. An anti-glare protection device for a welding mask, comprising: a transmission control circuit for determining a darkening signal from a control signal, a filter drive circuit for driving a controllable optical filter to a transmission value according to the signal input to the filter drive circuit, a welding activity detection circuit for detecting a welding activity, based on a first sensor signal from a first sensor circuit with at least one first sensor, wherein the welding activity detection circuit is arranged to control, via an activation switch, whether either the darkening signal from the transmission control circuit or a signal corresponding to an undarkened optical filter is input to the filter drive circuit, a manual input device allowing a user to adjust a user selected signal manually, a second sensor circuit with at least one second sensor for determining a sensed signal, wherein the second sensor circuit differs from the first sensor circuit, and a manually operable mode selection switch with a first signal input for the user selected signal and a second signal input for the sensed signal from the second sensor circuit unit for selecting either, in a manual mode, the user selected signal or, in an automatic mode, the sensed signal to be used as the control signal, and with a signal output for the control signal to the transmission control circuit for determining the darkening signal from the control signal.