We fielded a question from a customer today asking, “How dark can you make a lens? I want the darkest lens you can make.” Typically we’d take a polarized grey lens, do a dark grey after-tint, and then we’d apply a solid mirror on top of it, usually in silver. This leads to our darkest possible lens, which is approx. 95% blockage. The caveat in this case is that he obviously needs a non-polarized lens, which makes it more difficult to achieve a dark lens.
The darkest lens we can do, in this case, is either:
A) apply a saturated grey tint, which we do by hand right here in-house, and then put the solid silver mirror on it. This would give about a 75-85% blockage.
or B) Take a Transition Extra Active lens and put the same silver mirror on it. In its clear state, the lens will still be fully-functional and will look mostly clear. As the lens Transitions, and keep in mind the Extra Active lens is the darker Transition option so it gets quite dark, the mirror comes into full-effect and appears silver. It’s a pretty cool effect, and in the dark state it will reach something between 80-90%.
C) Is more of a consideration, rather than an actual lens option, but it’s worth noting that the physical blockage provided by a frame makes a different with light blockage. If you’re looking for a dark optical experience, a curved frame that really hugs your face and doesn’t let a lot of light in behind the lenses will seem much darker to you than a flatter frame that allows peripheral light to easily enter your eye area.
My final point would be D) that a dark lens will help against the sun, but I’ve heard some pilots explain that it potentially makes it tricky to see the instrumentation in the cockpit, simply because it’s too dark.