On Sat, 27 Dec 2014 23:12:53 -0800, "Julie Bove"
> wrote:
>
>
> "sf" > wrote in message
> ...
> > On Sat, 27 Dec 2014 22:53:07 -0500, Someone Else >
> > wrote:
> >
> >> Julie Bove wrote:
> >> >
> >> > "Someone Else" > wrote in message
> >> > ...
> >> >>>
> >> >> You missed the point. I have sunglasses. Others are saying their
> >> >> Transitions lenses work in their cars. Mine don't. They don't work
> >> >> in my friends 2009 F-150 either.
> >> >
> >> > I do remember a person telling me this when I got my glasses that they
> >> > wouldn't work in a car. I told her that mine always did. And they
> >> > still seem to. Now it could be that it is the UV protection that
> >> > doesn't work but they do get dark and that's all that matters for me.
> >> > If the car has UV protection built in... Right?
> >> >
> >> Correct. And most newer cars do.
> >
> > How do you know the UV protection isn't working? If they're getting
> > dark the UV protection is working.
>
> I don't know about that.

That's how photochromic lenses work.

> You can get cheap sunglasses with no UV protection
> but it all seems a moot point if the car has it anyway.

Yes to both points (especially the one about the problem being moot if
the car's UV is doing such a good job that the glasses don't
activate), but neither answers how s/he knows that the UV protection
isn't working even though they are changing color anyway.

--
A kitchen without a cook is just a room