WELD ARC MONITORING DEVICE

摘要

PURPOSE:To display clearly a portion other than an arc portion by providing a liquid crystal to partially dim a high luminance arc portioon an image pickup surface formed on an optical filter and a photo sensor to reduce a transmittance of the liquid crystal. CONSTITUTION:An arc light is detected by the photo sensor 21 such as photo transistor and the detection signal 22 is used to operate the liquid crystal driving circuit 23 to reduce the transmittance of the dimmer filter 19 and the liquid crystal portion 24 of the dimmer filter 12 with partially different transmittance. This makes it possible to obtain a television picture with the light quantity of the arc portion checked and to display clearly not only the arc portion but also the other portion in the groove.