Auto-darkening filter and auto-darkening system and welding mask comprising the same

Abstract

An auto-darkening filter, comprising a liquid crystal cell assembly for controlling the shading and a liquid crystal cell assembly for adjusting the hue, wherein the liquid crystal cell assembly for controlling the shading comprises at least one positive liquid crystal cell assembly which is in a bright state when a voltage is not applied and is in a dark state when a voltage is applied; the liquid crystal cell assembly for adjusting the hue is secured to one side of the liquid crystal cell assembly for controlling the shading, the liquid crystal cell assembly for adjusting the hue comprises a polarizer proximate to the one side of the liquid crystal cell assembly for controlling the shading, an analyzer distal to the one side of the liquid crystal cell assembly for controlling the shading, and an electrically controlled birefringent liquid crystal cell which is located between the polarizer and the analyzer and capable of adjusting the hue based on a driving voltage, wherein directions of polarization axes of the polarizer and the analyzer are not parallel to each other and the electrically controlled birefringent liquid crystal cell has a liquid crystal twisted angle of greater than 90 degrees. The present application further an auto-darkening system and a welding mask comprising the auto-darkening filter which enable simultaneous control of the shading and adjustment of the hue during a welding operation.

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