As it is time for a new pair of glasses, I am once again searching for a frame that has a permanently mounted mirror and will accept prescription lenses. Has anyone seen such a thing?
I have never seen such a set of frames.
Glasses are expensive, and having a permanently mounted mirror would mean you'd have the mirror there at all times when wearing that set.
I have cycling-specific frames, which have a prescription insert behind the big curved plastic, but they're not great and mounting a mirror on the frames would have downsides
- makes them unbalanced
- increases the risk of something snagging the mirror and tearing the glasses off
- obscures a sector of your vision somewhere in the plane of vision
There do exist mirrors that temporarily clip onto one's glasses frames by securing to one temple. I tried one and was very unhappy with the sharp spike right near my eyeball.
You can also get some that secure to a helmet. I found they were rarely in the correct position, and also managed to block out some of the horizon.
Depending on your bike style, I've had excellent results from a bar-end mirror on a road bike with drop bars, and a stalk mirror on my recumbent (where a mirror is absolutely mandatory)
Some googling turned up Hindsight, at https://hindsight.store/ but they can't offer prescription lenses.
Some day in the future we might see a Heads Up Display projected somewhere, but for now that's not something we can buy.