Tim+ wrote:

Chris Green wrote:

I'm sure they'd have been banned or come with all sorts of warnings if
they don't darken quick enough.

I imagine that the glass probably absorbs most of the UV, the LCD side of
things probably just brings the light level down to manageable limits. I
could be wrong of course.

If you look and AvE's (Arduino vs Evil) videos on youtube, he did a few
on LCD welding helmets, looking at the detection vs darkening times,
transmission of IR/UV/visible light etc.