FWIW, I had my Aviators fitted with specy lenses, specially calculated for cockpit use. They are bi-focals and the near-vision area sits higher than in normal bifocals (so as to cover the whole panel) and has also been calculated for the greater distance from seat to panel (as opposed to 'normal' reading glasses). They are graduated with the bottom bit being very light and the top rather dark, thus avoiding the problem of not seeing enough inside the cockpit. Took me a little while to explain all that to the optician, but they work a treat. And yes, I probably DO look like 70s porn producer, but who cares
PS: under FAA regs, polarized sunglasses are
NOT permitted to be worn by a crewmember, for exactly the reasons mentioned by rotorcraig and also because if your a/c has a heated windshield you will get interference.
