Tinted eyeglasses and sunglasses

[augest]

I've know that the tinted eyeglasses (http://www.firmoo.com/) can act as sunglasses for people who are myopia or hyperopia.

But are the tinted lenses with no prescription exactly same as sunglasses lenses? I guess there might be some difference between them.

Anyone who can tell me the difference or just they are the same.

Thanks a lot!