foggytown wrote:
Has anyone ever seen such? I mean real safety goggles that also give,
say, 3X magnification over the entire lens - not just a little spot

Your visual field is 180 degrees wide, and if there were a 3x
full-field magnifier,
that would narrow to 60 degrees. That would be a wide-field telescope,
not a simple magnifier. There's an outfit that makes
eyeglass/telescope
hybrids, Designs for Vision; my dentist likes their product.

http://www.designsforvision.com/DentHtml/DStdTel.htm

Magnifiers require you to get closer to the subject, so items at arm's
length (like
the saw kerf) might not be easy to see unless you lean in real close
(or move the lens
close to the kerf, i.e. detach it from your faceplate area). If you
had a full-face magnifier,
it's just like getting closeup glasses; things farther than a foot are
out of focus.

So you have three choices: lens-magnification in a portion of the
visual field (for close-in
objects only); tele-magnification in a portion of the visual field
(small telescopes, so you
can see things at a safe distance); close-up specs and items blur in
the distance.