[itishappy]

Bifocals in general are quite useful. It's nice to be able to see the road and the speedometer using the same lenses.

Traditional bifocals and progressives are different beasts. The hard outline on traditional bifocals means you get essentially two different lenses, both able to function as intended. The soft blend on progressives means you get essentially one big blurry lens that does not have well defined properties anywhere.

[EvanAnderson]

> The soft blend on progressives means you get essentially one big blurry lens that does not have well defined properties anywhere.

That seems to be exactly my experience with them, stated very succinctly. I've had these about 9 months and I'm still struggling with the ergonomics daily. I think I made the wrong choice.

[nikolay]

I used the wrong term, sorry. My concern applies to both bifocals and progressive lenses, though: aren't drivers trading off convenience over safety? Shouldn't we have at least two pairs of glasses - one for driving, and another for everything else?

[sokoloff]

When driving, I need to see things far away (mostly) but also on my dash/instrument cluster.

I am near-sighted overall and have needed distance glasses all my driving life. I got progressives last year and driving is safer now as I have a small area that I can use to clearly (and quickly!) read the instruments, the radio (read: map), defroster controls, etc.

In my case, not having multi-focal lenses was prioritizing convenience/laziness/cost over safety.

[itishappy]

No worries, I understood your intent!

The impact is a lot less than you may expect. Brains are ridiculously good at filling in incomplete information. For example, did you know that you have a roughly sun-sized blind spot slightly off center in each eye (where the optic nerve attaches)?

Now imagine needing to switch glasses to read your dash. Inconvenient and unsafe!